ARTICLE | doi:10.20944/preprints202106.0691.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Calcitriol; Vitamin D3; Glioblastoma; Glioblastoma stem-like cells
Online: 29 June 2021 (08:37:43 CEST)
: Glioblastoma (GBM) is the most common and most aggressive primary brain tumor with a very high rate of recurrence and a median survival of 15 months after diagnosis. Abundant evi-dence suggests that a certain sub-population of cancer cells harbors a stem-like phenotype and is likely responsible for disease recurrence, treatment resistance and potentially even for the infil-trative growth of GBM. GBM incidence has been negatively correlated with the serum levels of 25-hydroxy-vitamin D3, while the low pH within tumors has been shown to promote the ex-pression of the vitamin D3-degrading enzyme 24-hydroxylase, encoded by the CYP24A1 gene. Therefore, we hypothesized that calcitriol can specifically target stem-like glioblastoma cells and induce their differentiation. Here, we show using in vitro limiting dilution assays, quantita-tive real-time PCR and ex vivo adult organotypic brain slice transplantation cultures that thera-peutic doses of calcitriol, the hormonally active form of vitamin D3, reduces stemness to varying extent in a panel of investigated GSC lines and effectively hinders tumor growth of responding GSCs ex vivo. We further show that calcitriol synergizes with Temozolomide ex vivo to com-pletely eliminate some GSC tumors. These findings indicate that calcitriol carries potential as an adjuvant therapy for a subgroup of GBM patients and should be analyzed in more detail in fol-low-up studies.
ARTICLE | doi:10.20944/preprints201905.0221.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: brain cancer; glioblastoma multiforme; giant cell glioblastoma; prognosis
Online: 17 May 2019 (08:40:33 CEST)
Brain cancer is the tenth leading cause of death in the U.S. Glioblastoma multiforme (GBM) is the most lethal primary malignant central nervous system tumor in adults. The present study employed samples from 1985-2014 to discover the difference in prognosis among glioblastoma subtypes after the evolution of treatment modalities over the past few years. The current study aims to find the differences between Glioblastoma multiforme (GBM) and giant cell glioblastoma (GCG) in terms of prognosis among adults and elderly patients in the U.S. This study is a historical cohort type of study and is conducted on adults and elderly individuals with GBM or GCG from the years 1985-2014 in the U.S. Data were collected from the Surveillance, Epidemiology, and End Results Program (SEER) database. The study exposure was GBM or GCG and the outcome was mortality. The potential confounders were age, sex, race, ethnicity, year of diagnosis, primary site, and surgery. A chi-square test was used for categorical data. A univariate analysis was used for variables having a p-value < 0.05. Potential confounders were selected and evaluated using multivariate logistic regression models to calculate the odds ratio with stepwise selection. The study sample was 25,117. The incidences of GBM and GCG were not similar in relation to age group. Also, Spanish-Hispanic ethnicity was independently protective of GBM and GCG as compared to Non-Spanish-Hispanic ethnicity patients with GBM have a higher mortality rate than do GCG patients. The mortality rate was higher among patients diagnosed before 2010. In conclusion, GCG was not statistically significant in association to reduced mortality. Non-Spanish-Hispanics with GBM or GCG had a higher mortality rate than did Spanish-Hispanics. Factors such as being female, being age >59, and having a year of diagnosis before 2010 were independently associated with increased mortality.
REVIEW | doi:10.20944/preprints202308.1054.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: Glioblastoma; Tumour microenvironment; Aptamer; Therapeutic
Online: 15 August 2023 (05:05:31 CEST)
The key challenges to treating glioblastoma multiforme (GBM) are the heterogenous and complex nature of the GBM tumour microenvironment (TME) and difficulty of drug delivery across the blood-brain barrier (BBB). The TME is composed of various neuronal and immune cells, as well as non-cellular components including metabolic products, cellular interactions, and chemical compositions, all of which play a critical role in GBM development and therapeutic resistance. In this review, we aim to unravel the complexity of the GBM TME, evaluate current therapeutics targeting this microenvironment, and lastly identify potential targets and therapeutic delivery vehicles for the treatment of GBM. Specifically, we explore the potential of aptamer-targeted delivery as a successful approach to treating brain cancers. Aptamers have emerged as promising therapeutic drug delivery vehicles with the potential to cross the BBB and deliver payloads to GBM and brain metastases. By targeting specific ligands within the TME, aptamers could potentially improve treatment outcomes and overcome the challenges associated with larger therapies such as antibodies.
REVIEW | doi:10.20944/preprints202307.1595.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: Glioblastoma, Notch signaling, lncRNAs, miRNAs
Online: 24 July 2023 (10:51:59 CEST)
Glioblastoma multiforme (GBM) is a highly invasive brain malignancy originating from astrocytes, accounting for approximately 30% of central nervous system malignancies. Despite advancements in therapeutic strategies including surgery, chemotherapy, and radiopharmaceutical drugs, the prognosis for GBM patients remains dismal. The aggressive nature of GBM necessitates the identification of molecular targets and the exploration of effective treatments to inhibit its proliferation. The Notch signaling pathway, which plays a critical role in cellular homeostasis, becomes deregulated in GBM, leading to increased expression of pathway target genes such as MYC, Hes1, and Hey1, thereby promoting cellular proliferation and differentiation. Recent research has highlighted the regulatory role of non-coding RNAs (ncRNAs) in modulating Notch signaling by targeting critical mRNA expression at the post-transcriptional or transcriptional levels. Specifically, various types of ncRNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), have been shown to control multiple target genes and significantly contribute to the carcinogenesis of GBM. Furthermore, these ncRNAs hold promise as prognostic and predictive markers for GBM. This review aims to summarize the latest studies investigating the regulatory effects of ncRNAs on the Notch signaling pathway in GBM.
REVIEW | doi:10.20944/preprints202307.0968.v1
Subject: Medicine And Pharmacology, Clinical Medicine Keywords: glioblastoma, photomedicine, photodynamic therapy, photosensitizer
Online: 14 July 2023 (09:08:15 CEST)
Over the last 20 years, gliomas have made up over 89% of malignant CNS tumor cases in the American population (NIH SEER). Within this, glioblastoma is the most common subtype, comprising 57% of all glioma cases. Highly aggressive, this deadly disease is known for its high genetic and phenotypic heterogeneity, rendering a complicated disease course. The current standard-of-care consists of maximally safe tumor resection concurrent with chemoradiotherapy. However, despite advances in technology and therapeutic modalities, rates of disease recurrence are still high and survivability remains low. Given the delicate nature of the tumor location, remaining margins following resection often initiate disease recurrence. Photodynamic therapy (PDT) is a therapeutic modality that, following the administration of a non-toxic photosensitizer, induces tumor-specific anti-cancer effects after localized, wavelength-specific illumination. Its effect against malignant glioma has been studied extensively over the last 30 years, in pre-clinical and clinical trials. Here, we provide a comprehensive review of the three generations of photosensitizers alongside their mechanisms of action, limitations, and future directions.
REVIEW | doi:10.20944/preprints202111.0531.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: brain tumors; glioblastoma; angiogenesis; metformin
Online: 29 November 2021 (12:30:08 CET)
Glioblastoma (GBM) is the most common primitive tumor in adult central nervous system (CNS), classified as grade IV according to WHO 2016 classification. GBM shows a poor prognosis with an average survival of approximately 15 months, representing an extreme therapeutic challenge. One of its distinctive and aggressive features is aberrant angiogenesis, which drives tumor neovascularization, representing a promising candidate for molecular target therapy. Although several pre-clinical studies and clinical trials have shown promising results, anti-angiogenic drugs have not led to a significant improvement in overall survival (OS), suggesting the necessity of identifying novel therapeutic strategies. Metformin, an anti-hyperglycemic drug of the Biguanides family, used as first line treatment in Type 2 Diabetes Mellitus (T2DM), demonstrated in vitro and in vivo antitumoral efficacy in many different tumors, including GBM. From this evidence, a process of repurposing of the drug has begun, leading to the demonstration of the inhibition of various oncopromoter mechanisms and, consequently, to the identification of the molecular pathways involved. Here, we review and discuss the potential metformin’s antitumoral effects on GBM, inspecting if it could properly act as an anti-angiogenic compound to be considered as a safely add-on therapy in the treatment and management of GBM patients.
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: glioblastoma; MGMT; lomeguatrib; radiosensitivity; radiotherapy
Online: 3 June 2021 (10:44:21 CEST)
Background: Treatment resistance of glioblastoma multiforme to chemo- and radiotherapy remains a challenge yet to overcome. Especially MGMT promoter unmethylated patients have only little benefit from chemotherapy treatment using temozolomide since MGMT counteracts its therapeutic efficacy. Therefore, new treatment options in radiotherapy need to be developed to inhibit MGMT and increase radiotherapy response. Methods: Lomeguatrib, a highly specific MGMT inhibitor was used to inhibit MGMT protein expression in vitro. Radiosensitivity of established human glioblastoma multiforme cell lines in combination with lomeguatrib was investigated using the clonogenic survival assay. Inhibition of MGMT was analyzed using Western Blot. Cell cycle distribution and apoptosis were investigated to determine the effects of lomeguatrib alone as well as in combination with ionizing radiation. Results: Lomeguatrib significantly decreased MGMT protein expression and reduced radiation-induced G2/M arrest. A radiosensitizing effect of lomeguatrib was observed when administered at 1 µM and increased radioresistance at 20 µM. Conclusion: Low concentrations of lomeguatrib elicit radiosensitization, while high concentrations mediate a radioprotective effect.
ARTICLE | doi:10.20944/preprints202103.0280.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: HLA; MHC; glioblastoma; immunogenetics; Koreans
Online: 10 March 2021 (13:09:25 CET)
Purpose Immune responses for cancer cells can be altered according to genetic variation of human leukocyte antigen (HLA). Association of HLA polymorphism with risk of various cancer types is well known. However, the association between HLA and glioblastoma (GBM) remains uncertain. We sought to evaluate the association of HLA polymorphism with risk of GBM development in Koreans. Materials and Methods A case-control study was performed to identify the odds ratios (OR) of HLA class I and II genes for GBM. The control group consisted of 142 healthy Korean volunteers, and the GBM group was 80 patients with newly diagnosed GBM at our institution. HLA class I (-A, -B, and –C) and class II (-DR, -DQ, and –DP) genotyping was performed by high-resolution polymerase chain reaction (PCR)-sequence-based typing (PCR-SBT) methods. Results There were significantly decreased frequencies of HLA-A*26:02 (OR 0.22 CI 0.05-0.98), HLA-C*08:01 (OR 0.29 CI 0.10-0.87), and HLA-DRB1*08:03 (OR 0.32 CI 0.11-0.98), while there was significantly increased frequency of HLA-C*04:01 (OR 2.29 CI 1.05-4.97). In analysis of haplotypes, the frequency of DRB1*14:05-DQB1*05:03 was significantly decreased (OR 0.22 CI 0.05-0.98). Conclusion This study suggests that genetic variations of HLA may affect GBM development in Koreans. Further investigations with larger sample sizes are needed to delineate any potential role of the HLA polymorphisms in the pathogenesis of GBM development.
REVIEW | doi:10.20944/preprints202102.0500.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Glioblastoma; Neurodegeneration; Injury; Regeneration; Drosophila
Online: 23 February 2021 (08:15:48 CET)
The c-Jun N-terminal Kinase (JNK) signalling pathway is a conserved response to a wide range of internal and external cellular stress signals. Besides the stress response, the JNK pathway is involved in a series of vital regulatory mechanisms during development and adulthood that are critical to maintain tissue homeostasis. These mechanisms include the regulation of apoptosis, growth, proliferation, differentiation, migration and invasion. The JNK pathway has such a diverse functionality and cell-tissue specificity, that it has emerged as a key player in regeneration, tumorigenesis and other pathologies such as neurodegenerative diseases. The JNK pathway is highly active in the central nervous system (CNS), and plays a central role for the cells to cope with pathophysiological insults during both development and adulthood. Among the many mechanisms described in the literature, in this review we focus on the JNK pathway functions in pathologies of the CNS. More specifically, we discuss some newly identified examples and mechanisms of JNK-driven tumor progression in glioblastoma, regeneration/repair after an injury in the CNS, neurodegeneration, and neuronal cell death. Recent studies have shown that the JNK pathway regulates matrix metalloproteinases (MMPs) production in response to cytoneme/tumor microtubes formation and Wingless (Wg)/WNT pathway activation in glioblastoma cells. Thus, JNK pathway is essential for glioblastoma progression, infiltration and non-autonomous induction of neurodegeneration. In regeneration, the JNK pathway controls Draper (Drpr) expression in glial cells that mediate engulfment and regeneration of the CNS upon injury.
ARTICLE | doi:10.20944/preprints202008.0096.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: MGMT methylation; MSP; dp_qMSP; glioblastoma
Online: 4 August 2020 (11:34:58 CEST)
The promoter hypermethylation of the methylguanine-DNA methyltransferase (MGMT) gene is a frequently used biomarker in daily clinical practice as it is associated with a favorable prognosis in glioblastoma patients treated with temozolamide. In this study we carried out a clinical validation of a quantitative assay for MGMT methylation detection by comparing a novel MSP custom assay using double-probe characteristics (dp_qMSP) with the conventional MSP in 100 FFPE glioblastoma samples collected from a prospective study in La Paz University Hospital. We realized both determinations and established the best cutoff for the identification of positive-methylated samples using the quantitative data obtained from dp_qMSP. Kaplan-Meier curves and ROC time dependent or ROC(t) curves were employed for the comparison of both methodologies. Our results indicate that the optimal cutoff to categorize the MGMTm positive samples by using dp_qMSP is 3.75% methylation value. We obtained similar results using both assays in the same cohort of patients, in terms of progression free survival (PFS) and overall survival (OS) when analyzing the Kaplan-Meier curves. The results of ROC(t) curves showed that dp_qMSP increases the AUC (t) in comparison with MSP for predicting PFS and OS over time. We conclude that dp_qMSP is an alternative methodology compatible with the results obtained with the conventional MSP. This easy-to-use, objective and reliable methodology provides quantitative results and improves the diagnostic precision of patients with glioblastoma in terms of PFS and OS, making it a more competitive assay, suitable for clinical practice.
ARTICLE | doi:10.20944/preprints202211.0486.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma; Radioresistance; Radiosensitizer; ROS; Nanoparticle; Radiotherapy
Online: 28 November 2022 (01:48:04 CET)
Nanoparticle-mediated radiation therapy (NPRT) is an emerging modality for radiosensitization of highly resistant cancers such as brain cancers. This is due to the ability of specific nanoparticles (NPs) to increase physical dose deposition and subsequent direct damage to cells and DNA within their local vicinity, through enhanced generation of reactive oxygen species, ROS. Here, we report the successful use of PEGylated (biocompatible) core-shell quantum dots (QDs) and carbon quantum dots (CQDs) to simultaneously enhance and assess ROS generation while radiosensitizing highly radioresistant brain cancer cell lines: T98G and U87 Glioblastoma cells. Relative peak fluorescence intensity ratio calculations and average intensity comparisons show highly significant (***p<0.001) enhancement of ROS generation, for 5 Gy and 20 Gy irradiation, applied using a Faxitron Cell Irradiator. By quantifying post-radiotherapy cell attachment, proliferation, migration, cell survival and cell death using electric cell-substrate impedance sensing and clonogenic assays, we demonstrate potentially improved in vitro radiotherapeutic outcomes for brain cancer cells radiosensitized using PEGylated CdSe/ZnS QDs and CQDs.
ARTICLE | doi:10.20944/preprints201901.0315.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; p53; apoptosis; doxorubicin; bortezomib; vorinostat.
Online: 30 January 2019 (13:03:22 CET)
In prostate cancer, p53 maximizes apoptosis in response to severe DNA damage, not DNA replication stress. Here, we examined the apoptotic response of two glioblastoma cells, p53-wild type U87 and a p53-mutated T98G cell, for the same stresses. We ascertained that p53 intensified apoptosis in response to severe DNA damage, not DNA replication stress in glioblastoma. We further asked if p53-mediated apoptosis can be induced by cellular stress other than severe DNA damage. We analyzed two compounds, bortezomib and vorinostat, respective inhibitors of 26S proteasome and histone deacetylase, to evaluate their capacity to activate p53-mediated apoptosis. The cellular stress incited by bortezomib, not vorinostat, activated p53-mediated apoptosis. Next, we asked if the cellular stress generated by combining the two compounds had a synergistic effect on apoptosis. Our results demonstrated that doxorubicin with bortezomib or CFS-1686, or bortezomib with vorinostat have a significant synergistic effect on apoptosis only in p53-wild type cell. Under high stress, p53 translocates from cytosol into the nucleus to cause apoptosis possibly. Together, p53 maximizes apoptosis for cellular stress caused by severe DNA damage, disruption of protein turnover, and for the stress induced by drug combination including doxorubicin with bortezomib or CFS-1686, and bortezomib with vorinostat.
REVIEW | doi:10.20944/preprints202103.0342.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; high-grade glioma; refractory glioma; direct delivery; convection enhanced delivery; neuro-oncology; refractory glioblastoma; clinical trials
Online: 12 March 2021 (15:01:51 CET)
Development of effective treatments for high-grade glioma (HGG) is hampered by 1) the blood-brain barrier (BBB), 2) an infiltrative growth pattern, 3) rapid development of therapeutic resistance, and, in many cases, 4) dose-limiting toxicity due to systemic exposure. Convec-tion-enhanced delivery (CED) has the potential to significantly limit systemic toxicity and in-crease therapeutic index by directly delivering homogenous drug concentrations to the site of disease. In this review, we present clinical experiences and preclinical developments of CED in the setting of high-grade gliomas.
REVIEW | doi:10.20944/preprints202012.0239.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: glioblastoma; high-grade glioma; refractory glioma; virotherapy; oncolytic viruses; neuro-oncology; refractory glioblastoma; chimeric viruses; clinical trials
Online: 9 December 2020 (20:13:56 CET)
As new treatment modalities are being explored in neuro-oncology, viruses are emerging as a promising class of therapeutics. Virotherapy consists of introduction of either wild-type or engineered viruses to the site of disease, where they exert anti-tumor effect. These viruses can either be non-lytic, in which case they are used to deliver gene therapy, or lytic, which induce tumor cell lysis and subsequent host immunologic response. Replication-competent viruses can then go on to further infect and lyse neighboring glioma cells. This treatment paradigm is being explored extensively in both preclinical and clinical studies for a variety of indications. Virus-based therapies are advantageous due to the natural susceptibility of glioma cells to viral infection, which improves therapeutic selectivity. Furthermore, lytic viruses expose glioma antigens to the host immune system and subsequently stimulate an immune response that specifically targets tumor cells. This review surveys the current landscape of oncolytic virotherapy clinical trials in high-grade glioma, summarizes preclinical experiences, identifies challenges associated with this modality across multiple trials, and highlights potential to integrate this therapeutic strategy into promising combinatory approaches.
REVIEW | doi:10.20944/preprints202310.0607.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: Glioblastoma; Transcription factors; Neoantigens; Personalized therapy; Epigenetics
Online: 10 October 2023 (09:55:19 CEST)
Glioblastoma (GBM) is one of the most aggressive and intricate forms of brain cancer, demanding novel therapeutic interventions. The role of transcription factors in epigenetic regulation has emerged as a promising avenue for targeting GBM. This comprehensive review seeks to explore the complex interplay between specific transcription factors such as SNAI2, FOXA1, YAP1, TWIST1, ZEB1, and NF-kB, and their role in GBM progression and therapy. The focus extends to innovative therapeutic strategies, including epigenetic modifiers, targeted therapies, and CRISPR/Cas9 technology. A unique aspect of this review highlights the connection between transcription factors, neoantigen presentation, and personalized immunotherapy in GBM. By delving into current research, clinical trials, and immunological data, this review emphasizes the significant potential of targeting transcription factors for personalized immunotherapy in GBM. The challenges, future perspectives, and ethical considerations are also critically discussed, offering a complete and thought-provoking insight into a vital and rapidly evolving field.
ARTICLE | doi:10.20944/preprints202307.0471.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; metabolomic profiling; biogenic amines; concurrent chemoradiation.
Online: 7 July 2023 (08:03:04 CEST)
Introduction: This study aims to characterize changes in biogenic amines patterns in glioblasto-ma patients undergoing surgery and concurrent chemoradiation to illustrate how this class of metabolites changes during different stages of standard care treatment protocol. Methods: We examined 138 plasma specimens (before surgery, 2 days after surgical resection, before starting concurrent chemoradiation, immediately after chemoradiation, and after adju-vant chemotherapy treatment) from 36 patients with isocitrate dehydrogenase (IDH) wildtype glioblastoma. Untargeted GC-TOF mass spectrometry-based metabolomics of biogenic amines was used given its superiority for identifying and quantitating small metabolites; this yielded 340 structurally identified metabolites. Results: Comparing post-surgery to pre-surgery showed increased level of 12 metabolites: Gly-codeoxycholic acid (P=7.79E-05), Betonicine (P=9.23E-05), Glycocholic acid (P=3.18E-03), 3-Cysteinylaectaminophen (P=4.95E-03), S-Methyl-3-thioacetaminophen (P=5.77E-03), Tau-rocholic acid (P=9.97E-03), N-glycine (P=0.0013), p-acetamidophenyl.beta.-D-glucuronide (P=0.0048), 2-Hydroxy-5-sulfopyridine-3-carboxylic acid (P=0.0074), Acetaminophen sulfate (P=0.0095), 2-Amino-3-methoxybenzoic acid (P=0.02), and Dehydrofelodipine (P=0.024). There were 11 compounds that were downregulated, which included Mannitol (P=1.96E-19), Sorbitol (P=2.75E-019), Linoleic acid (P=1.51E-10), 1-Methylnicotinamide (P=1.78E-09), Nudifloramide (P=2.81E-08), Hexadecanedioic acid (P=5.49E-05), 3-Hydroxybutyric acid (P=0.0002), Riluzole (0.0036), Bupivacaine (P=0.0041), Lactitol (P=0.008), and 1-hydroxymidazolam.beta.-D-glucuronide (P=0.0414). After chemoradiation, significant de-crease was uncovered in Famotidine (P=0.0074), N-Isovalerylglycine (P=0.012), and 3-Methylcrotonylglycine (P=0.0131). While significant increase was detected in N-Methylisoleucine (P=0.0011), 4-Methyl-5-thiazoleethanol (P=0.042), and 6-Hydroxycaproic acid (P=0.049). Ensemble learning models, specifically random forest (RF) and AdaBoost (AB), accurately classified treatment phases with high accuracy (RF: 0.81 ± 0.04, AB: 0.78 ± 0.05). One significant insight gleamed from these models were that the metabolites Sorbitol and N-methylisoleucine were identified as important predictive features and confirmed by SHAP analysis. Conclusion: To our knowledge, this is the first study to describe plasma biogenic amines signa-tures during different treatment phases in patients with glioblastoma. A larger study is needed to confirm the results and the potential application of this algorithm for classification of treatment responses.
ARTICLE | doi:10.20944/preprints202304.0565.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: Chrysomycin A; Xenograft mouse model; Glioblastoma; Apoptosis
Online: 19 April 2023 (08:00:29 CEST)
Glioblastoma (GBM) is a major type of primary brain tumors without ideal prognosis and it’s necessary to find novel compound possessing therapeutic effect. Chrysomycin A (Chr-A) has been reported to inhibit the proliferation, migration and invasion of U251 and U87-MG cells, but the mechanism of Chr-A against glioblastoma in vivo and whether Chr-A modulates apoptosis of neuroglioma cells is unclear.The present study was to elucidate the potential of Chr-A against glioblastoma in vivo and how Chr-A modulates apoptosis of neuroglioma cells. Briefly, The an-ti-glioblastoma activity was assessed in human glioma U87 xenografts nude mice. Chr-A-related targets were identified by RNA-seq. Apoptotic ratio and caspase 3/7 activity of U251 and U87-MG cells were assayed by flow cytometry. Apoptosis-related proteins and possible molecular mecha-nism were validated via Western blotting. The results showed that Chr-A treatment significantly inhibits glioblastoma progression in xenografts nude mice, and enrichment analysis suggested that apoptosis, PI3K-Akt and Wnt signaling pathway were involved in the possible mechanism. Chr-A increased apoptotic ratio and the activity of caspase 3/7 in U251 and U87-MG cells. Western blot revealed that Chr-A broke the balance between Bax and Bcl-2 activating caspase cascade re-action and downregulated the expression of p-Akt and p-GSK-3β, suggesting that Chr-A may contribute to glioblastoma regression modulating Akt/GSK-3β signaling pathway to promote apoptosis of neuroglioma cells in vivo and in vitro. Therefore, Chr-A may hold therapeutic promise for glioblastoma.
ARTICLE | doi:10.20944/preprints202209.0218.v1
Subject: Chemistry And Materials Science, Theoretical Chemistry Keywords: Scutellaria baicalensis; phytochemicals; glioblastoma multiforme; in silico
Online: 15 September 2022 (03:55:58 CEST)
Epidermal Growth Factor Receptor (EGFR) tyrosine kinase is a cell surface receptor whose overexpression has been associated with different types of cancers including brain cancer (glioblastoma multiforme). The ability of the extract of Scutellaria baicalensis to inhibit the proliferation of malignant glioma cells have been reported. Thus, in this study we report the identification of 307 bioactive constituents responsible for the anti-glioblastoma multiforme effect from S. baicalensis using in silico studies such as molecular docking, binding free energy calculations, pharmacophore modelling, induced-fit docking, gene enrichment analysis, molecular dynamic simulations and ADMET predictions. A total of 307 chemical constituents of S. baicalensis were screened and the top 10 scoring compounds indicated different binding affinities ranging from -9.010 to -6.427 kcal/mol towards the EGFR tyrosine kinase; Ganhuangenin, 5,7,2',5'-tetrahydroxyflavone, (2R)-2-(2,6-dihydroxyphenyl)-3,4-dihydro-2H-chromene-5,7-diol, and tenaxin I possess higher binding affinities (-9.010 to -8.649 kcal/mol) compared to the standard ligand, erlotinib having -8.539 kcal/mol. The compounds interacted with amino acids of clinical importance such as MET 769, GLU 738, THR 766 via H-bond. The structural features involved in the interaction with the target were mostly two aromatic rings, H-bond donors and acceptors and some hydrophobic interactions which varies between the ligands. Better docking scores in the induced-fit docking further validates the inhibitory potential of the compounds against the flexible protein. All the top-scoring ligands from S. baicalensis had zero Lipinski violation and also obeyed other drug-likeness rules by Ghose, Veber, Egan, and Muegge with the exception of breviscapine. Interestingly, all the compounds are not likely to be hepatotoxic, mutagenic, or cytogenic, making them potentially safe as anti-cancer agents.
REVIEW | doi:10.20944/preprints202207.0225.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: blood brain barrier; physiological; pathological; glioblastoma; intervention
Online: 14 July 2022 (15:02:52 CEST)
The blood brain barrier (BBB) is an essential component in regulating and maintaining the homeostatic microenvironment of the central nervous system (CNS). During the occurrence and development of glioblastoma (GBM), BBB is pathologically disrupted with markedly increased permeability. Due to the obstruction imposed by the BBB, strategies currently employed for GBM therapeutics still obtain a very low success rate and lead to systemic toxicity. Moreover, chemotherapy could promote pathological BBB functional restoration, accompanied with a prominent decrease of intracerebral therapeutics transportion during GBM multiple administration, resulting in chemotherapy failure for GBM treatment. The effective delivery of therapeutics into the brain still faces with severe challenges. Regulation of pathological BBB for enhanced transporting of therapeutics across the barrier may provide new opportunities for effective and safe treatment of GBM. This article reviews the structure and function of BBB in physiological state, the mechanisms underlying BBB pathological fenestration during the development of GBM, and the therapeutic strategies of GBM based on BBB intervention and therapeutic drugs transporting across the BBB.
ARTICLE | doi:10.20944/preprints202112.0396.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; signal transduction; xenograft model; drug repositioning
Online: 23 December 2021 (16:53:54 CET)
Multimodal therapy including surgery, radiation treatment and temozolomide (TMZ) is performed on glioblastoma (GBM). However, the prognosis is still poor and there is an urgent need to develop effective treatments to improve survival. Molecular biological analysis was conducted to exam-ine the signal activation patterns at GBM specimens and remains an open problem. Advanced macrolides, such as azithromycin, reduce the phosphorylation of p70 ribosomal protein S6 kinase (p70S6K), a downstream mammalian target of rapamycin (mTOR) effector, and suppress the proliferation of T-cells. We focused on its unique profile and screened for the antitumor activity of approved macrolide antibiotics. Clindamycin (CLD) reduced the viability of GBM cells in vitro. We assessed the effects of the candidate macrolide on the mTOR pathway through Western blotting. CLD attenuated p70S6K phosphorylation in a dose dependent manner. These effects of on GBM cells were enhanced by co-treatment with TMZ. Furthermore, CLD inhibited the expression of O6-methylguanine-DNA methyltransferase (MGMT) protein in cultured cells. In the mouse xenograft model, CLD and TMZ co-administration significantly suppressed the tumor growth and markedly decreased the number of Ki-67 (clone MIB-1) positive cells within the tumor. These results suggest that CLD suppresses GBM cell growth by the inhibiting mTOR signaling. Moreover, CLD and TMZ showed promising synergistic antitumor activity.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: G9a; EHMT2; glioblastoma; medulloblastoma; epigenetics; brain tumor
Online: 8 October 2021 (10:57:22 CEST)
Epigenetic mechanisms, including post-translational modifications of DNA and histones that influence chromatin structure, regulate gene expression during normal development, and are also involved in carcinogenesis and cancer progression. The histone methyltransferase G9a (euchromatic histone lysine methyltransferase 2, EHMT2), which mostly mediates mono- and dimethylation by histone H3 lysine 9 (H3K9), influences gene expression involved in embryonic development and tissue differentiation. Overexpression of G9a has been observed in several cancer types, and different classes of G9a inhibitors have been developed as potential anticancer agents. Here, we review the emerging evidence suggesting the involvement of changes in G9a activity in brain tumors, namely glioblastoma (GBM), the main type of primary malignant brain cancer in adults, and medulloblastoma (MB), the most common type of malignant brain cancer in children. We also discuss the role of G9a in neuroblastoma (NB) and the drug development of G9a inhibitors.
ARTICLE | doi:10.20944/preprints202108.0135.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma; biomarker; TSPO; single nucleotide polymorphism; survival.
Online: 5 August 2021 (10:22:34 CEST)
Glioblastoma (GBM) is the most common primary brain tumor in adults, with few available therapies and a 5-year survival rate of 7.2%. Hence, strategies for improving GBM prognosis are urgently needed. The translocator protein 18kDa (TSPO) plays crucial roles in essential mito-chondria-based physiological processes and is a validated biomarker of neuroinflammation, which is implicated in GBM progression. The TSPO gene has a germline single nucleotide pol-ymorphism, rs6971, which is the most common SNP in the Caucasian population. High TSPO gene expression is associated with reduced survival in GBM patients; however, the relation between the most frequent TSPO genetic variant and GBM pathogenesis is not known. The present study ret-rospectively analyzed the correlation of the TSPO polymorphic variant rs6971 with overall and progression-free survival in GBM patients using three independent cohorts. TSPO rs6971 poly-morphism was significantly associated with shorter overall survival and progression-free survival in male GBM patients but not in females in one large cohort of 441 patients. We observed similar trends in two other independent cohorts. These observations suggest that the TSPO rs6971 pol-ymorphism could be a significant predictor of poor prognosis in GBM, with a potential for use as a prognosis biomarker in GBM patients. These results reveal for the first time a biological sex-specific relation between rs6971 TSPO polymorphism and GBM.
REVIEW | doi:10.20944/preprints202107.0355.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: circadian rhythms; clock genes; glioblastoma; tretament; chronotherapy
Online: 15 July 2021 (10:18:02 CEST)
Gliomas are solid tumors of the Central Nervous System (CNS) that originated from different glial cells. The World Health Organization (WHO) classified these tumors into four groups (I-IV) with increasing malignancy. Glioblastoma (GBM) is the most common and aggressive type of brain tumor classified as a grade IV. GBM are resistant to conventional therapies with poor prognosis after diagnosis even when the Stupp protocol that combines surgery and radiochemotherapy is applied. Nowadays, few novel therapeutic strategies have been used to improve GBM treatment, looking for higher efficiency and lower side effects, but with relatively modest results. The circadian timing system temporally organizes the physiology and behavior of most organisms and daily regulates several cellular processes in organs, tissues, and even in individual cells, including tumor cells. The potentiality of the function of the circadian clock on cancer cells modulation as a new target for novel treatments with a chronobiological basis offers a different challenge that needs to be considered in further detail. The present review will discuss state of the art regarding GBM biology, the role of the circadian clock in tumor progression, and new chrono-chemotherapeutic strategies applied for GBM treatment.
ARTICLE | doi:10.20944/preprints202012.0293.v2
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Hsp70; biomarker; glioblastoma; NK cells; clinical study
Online: 26 January 2021 (11:33:34 CET)
Despite rapid progress in the treatment of many cancers, glioblastoma remains a devastating disease with dismal prognosis. The aim of this study was to identify immune-related biomarkers that more effectively predict outcome of glioblastoma. Since heat shock protein 70 (Hsp70) and IL-2 are known to increase the expression of activatory NK cell receptors, recognizing aggressive human tumor cells that present Hsp70 on their cell surface, extracellular Hsp70 levels were determined in glioma patients together with activatory NK cell receptors. All gliomas are membrane Hsp70-positive (mHsp70+) and high grade gliomas more frequently show an overexpression of Hsp70 in the nucleus and cytosol. Significantly increased extracellular Hsp70 levels are detected predominantly in glioblastomas with large necrotic areas. Overall survival (OS) is more favorable in patients with low Hsp70 serum levels indicating that a high Hsp70 expression is associated with an unfavorable prognosis. Elevated frequencies of NK cells are associated with a more favorable outcome. Of caution, a glucocorticoid therapy reduces the prevalence of NK cells. In summary, elevated frequencies of Hsp70-reactive NK cells at diagnosis and lower Hsp70 levels predict a more favorable prognosis in glioblastoma patients.
REVIEW | doi:10.20944/preprints202008.0658.v1
Subject: Biology And Life Sciences, Virology Keywords: glioma; oncolytic virus; glioblastoma; virotherapy; brain tumor
Online: 30 August 2020 (11:17:24 CEST)
Glioma tumors are one of the most devastating cancer types. Of the different glioma tumors, glioblastoma is the most advanced stage with the worst prognosis. Current therapies are still unable to provide an effective cure. Recent advantages in oncolytic immunotherapy have generated great expectations in the cancer therapy field. The use of oncolytic viruses (OV) in cancer treatment is one of those immune-therapeutic alternatives. OV have a double oncolytic action by both, directly destroying the cancer cells, sparing the patient’s life, and stimulating a tumor specific immune response to revert the ability of tumors to escape the control of the immune system. OV are one promising alternative to conventional therapies in glioma tumor treatment. Several clinical trials have proven the feasibility to use some viruses to specifically infect tumors eluding undesired toxic effects in the patient. Here we have revisited the literature in order to describe the main OV proposed so far as therapeutic alternatives to destroy glioma cells in vitro and trigger tumor destruction in vivo. Some clinical trials are exploring the use of this therapy as an alternative were other approaches provide limited hope.
ARTICLE | doi:10.20944/preprints202008.0637.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; neural stem cells; replicative senescence; metastasis
Online: 28 August 2020 (11:33:23 CEST)
Due to its aggressive and invasive nature glioblastoma (GBM), the most common and aggressive primary brain tumour in adults, remains almost invariably lethal. Significant advances in the last several years have elucidated much of the molecular and genetic complexities of GBM. However, GBM exhibits a vast genetic variation and a wide diversity of phenotypes that has complicated the development of effective therapeutic strategies. This complex pathogenesis makes it necessary the development of experimental models that could be used to further understand the disease, and also to provide a more realistic testing ground for potential therapies. In this report, we describe the process of transformation of primary mouse embryo astrocytes into immortalized cultures with neural stem cell characteristics, that are able to generate of GBM when injected in the brain of C57BL/6 mice, or heterotopic tumours when injected iv. Overall, our results show that oncogenic transformation is a fate for NSC if cultured for long periods in vitro. In addition, since no additional hit is necessary to induce the oncogenic transformation, our model may be used to investigate the pathogenesis of gliomagenesis and to test the effectiveness of different drugs throughout the natural history of GBM.
ARTICLE | doi:10.20944/preprints201910.0318.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: nanoparticles; glioblastoma multiforme; radiosensitizers; external beam radiotherapy
Online: 28 October 2019 (10:46:14 CET)
Gold nanoparticles (GNPs) have demonstrated significant dose enhancement with kilovoltage (kV) X-rays however recent studies have shown inconsistent findings with megavoltage (MV) X-rays. We proposed to evaluate the radiosensitization effect in U87 glioblastoma (GBM) cells in the presence of 42 nm GNPs and irradiated with a clinical 6 MV photon beam. Cytotoxicity and radiosensitization was observed using MTS and clonogenic cellular radiation sensitivity assays respectively. Sensitization enhancement ratio was calculated for 2 Gy (SER2Gy) with GNP (100 μg/mL). Dark field and MTS assay revealed high co-localization and good biocompatibility of the GNPs with GBM cells. Significant sensitization enhancement of 1.45 (P = 0.001) was observed with GNP 100 μg/mL. Similarly, at 6 Gy there was significant difference in the survival fraction between GBM alone group (Mean (M) = 0.26, Standard Deviation (SD) = 0.008) and GBM plus GNP group (M = 0.07, SD = 0.05, P = 0.03). GNPs enable radiosensitization in U87 GBM cells at 2 Gy when irradiated using a clinical platform. In addition to the potential clinical utility of GNPs, these studies demonstrate the effectiveness of a robust and easy to standardise in-vitro model that can be employed for future studies involving metal nanoparticle plus irradiation.
ARTICLE | doi:10.20944/preprints202210.0308.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioma; Glioblastoma; Glioma stem-like cells; CHRDL1; BMP4
Online: 20 October 2022 (11:20:23 CEST)
Glioblastoma (GBM) still presents as one of the most aggressive tumors in the brain, which despite enormous research efforts remains incurable until today. As many theories evolve around the persistent recurrence of this malignancy the assumption of a small population of cells with a stem-like phenotype remains as a key driver of its infiltrative nature. In this article we research Chordin-like 1 (CHRDL1), a secreted protein, as a potential key regulator of the glioma stem-like cell (GSC) phenotype. It has been shown that CHRDL1 antagonizes the function of Bone Morphogenic Protein 4 (BMP4), which induces GSC differentiation and hence reduces tumorigenicity. We therefore employed two previously described GSCs spheroid cultures and depleted them of CHRDL1 using stable transduction of a CHRDL1-targeting shRNA. We show with in vitro cell based assays (MTT, limiting dilution and sphere formation assays), western blots, irradiation procedures and quantitative real-time PCR that depletion of the secreted BMP4 antagonist CHRDL1 prominently decreases functional and molecular stemness traits resulting in enhanced radiation sensitivity. As a result, we postulate CHRDL1 as an enforcer of stemness in GSCs and find additional evidence that high CHRDL1-expression might also serve as a marker protein to determine BMP4-susceptibility.
ARTICLE | doi:10.20944/preprints202107.0281.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Glioblastoma; Precision Medicine; Targeted Therapy; Genomics; Neuro-Oncology
Online: 13 July 2021 (09:28:35 CEST)
BACKGROUND: Glioblastoma (GBM) is driven by various genomic alterations. Next generation sequencing (NGS) could yield targetable alterations that may impact outcomes. The goal of this study was to describe how NGS can inform targeted therapy (TT) in this patient population. METHODS: The medical records of patients (pts) with a diagnosis of GBM from 2017-2019 were reviewed. Records of patients with recurrent GBM and genomic alterations were evaluated. Objective response rates and disease control rates were deter-mined. RESULTS: A total of 87 pts with GBM underwent NGS. Forty percent (n = 35) were considered to have actionable alterations. Of the 35, 40% (n=14) pts had their treatment changed due to an alteration. The objective response rate (ORR) of this population was 43%. The disease control rate (DCR) was 100%. The absolute mean decrease in contrast enhancing disease was 50.7% (95% CI 34.8 – 66.6). CONCLUSION: NGS for GBM, particularly in the recurrent setting, yields a high rate of actionable alterations. We observed a high ORR and DCR, reflecting the value of NGS in deciding on TT to match alterations that are likely to respond. In conclusion, patient selection and availability of NGS may impact outcomes in select pts with recurrent GBM.
ARTICLE | doi:10.20944/preprints202010.0046.v3
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Glioblastoma; master regulators; upstream analysis; IGFBP2; FRA-1; FOSL1; short term survivors; transcription factors
Online: 17 February 2021 (12:58:18 CET)
Only two percent of Glioblastoma multiforme (GBM) patients respond to standard care and survive beyond 36 months (long-term survivors, LTS) while the majority survive less than 12 months (short-term survivors, STS). To understand the mechanism leading to poor survival, we analyzed publicly available datasets of 113 STS and 58 LTS. This analysis revealed 198 differentially expressed genes (DEGs) that characterize aggressive tumor growth and may be responsible for the poor prognosis. These genes belong largely to the GO-categories “epithelial to mesenchymal transition” and “response to hypoxia”. In this paper we applied upstream analysis approach which involves state-of-art promoter analysis and network analysis of the dysregulated genes potentially responsible for short survival in GBM. Binding sites for transcription factors associated with GBM pathology like NANOG, NF-κB, REST, FRA-1, PPARG and seven others were found enriched in the promoters of the dysregulated genes. We reconstructed the gene regulatory network with several positive feedback loops controlled by five master regulators – IGFBP2, VEGFA, VEGF165, PDGFA, AEBP1 and OSMR which can be proposed as biomarkers and as therapeutic targets for enhancing GBM prognosis. Critical analysis of this gene regulatory network gives insights on mechanism of gene regulation by IGFBP2 via several transcription factors including the key molecule of GBM tumor invasiveness and progression, FRA-1. All the observations are validated in independent cohorts and their impact on overall survival is studied.
ARTICLE | doi:10.20944/preprints201910.0180.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: long term survival; Glioblastoma; IDH; EGFR; Ki67; p53
Online: 16 October 2019 (08:30:25 CEST)
Background: Glioblastomas (GBM) is generally burdened, to date, by a dismal prognosis, although Long Term Survivors have a relatively significant incidence. Our specific aim was to determine the exact impact of many surgery-, patient- and tumor-related variable on Survival parameters. Methods: The surgical, radiological and clinical outcomes of patients have been retrospectively reviewed for the present study. All the patients have been operated on in our Institution and classified according their Overall Survival in LTS (Long Term Survivors) and STS (Short Term Survivors). A thorough Review of our surgical series was conducted to compare the oncologic results of the patients in regards to 1. Surgical , 2. Molecular, and 3.Treatment related features. Results: A total of 177 patients were included in the final cohort. Extensive statistical analysis by means of univariate, multivariate and survival analyses disclosed a survival advantage for patients presenting a younger age, a smaller lesion and a better functional status at presentation. From the Histochemical point of view, Ki67(%) was the strongest predictor of better oncologic outcomes. A stepwise analysis of variance outlines the existence of 8 prognostic subgroups according to the molecular patterns of Ki67 overexpression and EGFR, p53 and IDH mutations. Conclusions: On the ground of our statistical analyses we can affirm that the following factors were significant predictors of survival advantage: KPS, Age, Volume of the lesion, Motor disorder at presentation, a Ki67 overexpression. A fine molecular profiling is feasible to precisely stratify the prognosis of GBM patients.
ARTICLE | doi:10.20944/preprints201805.0196.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: P-glycoprotein; glioblastoma multiforme; brain-blood barrier; doxorubicin
Online: 14 May 2018 (12:50:18 CEST)
P-glycoprotein (Pgp) determines resistance to a broad spectrum of drugs in glioblastoma multiforme (GB) because it is highly expressed in GB stem cells and in brain-blood barrier (BBB), the peculiar endothelium surrounding brain. Inhibiting Pgp activity in BBB and GB is still an open challenge. Here, we tested the efficacy of a small library of tetrahydroisoquinoline derivatives with an EC50 for Pgp < 50 nM, in primary human BBB cells and in patients-derived GB, from which we isolated differentiated/adherent cells (AC, i.e. Pgp-negative/doxorubicin-sensitive cells) and stem cells (neurospheres, NS, i.e. Pgp-positive/doxorubicin-resistant cells). At 1 nM, 3 compounds increased the delivery of doxorubicin, a typical substrate of Pgp, across BBB monolayer, without altering expression and activity of other transporters. The compounds increased the drug accumulation within NS, restoring necrosis, apoptosis and reduction in cell viability induced by doxorubicin. In co-culture systems, the compounds added to the luminal face of BBB increased the delivery of doxorubicin to NS growing under BBB and rescued the drug’s cytotoxicity. Our work identified new ligands of Pgp active at low nanomolar concentrations, that effectively reduce Pgp activity in BBB and GB, and can improve chemotherapy efficacy in this tumor.
ARTICLE | doi:10.20944/preprints201611.0126.v3
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: IQGAP1; glioblastoma multiforme (GBM); scaffold protein; podosome/invadosome
Online: 16 January 2017 (10:30:48 CET)
Glioblastoma multiforme (GBM) is the most frequent and aggressive primary brain tumor. GBM is formed by a very heterogeneous astrocyte population, neurons, neovascularization and infiltrating myeloid cells (microglia and monocyte derived macrophages). The IQGAP1 scaffold protein interacts with components of the cytoskeleton, cell adhesion molecules, and several signaling molecules to regulate cell morphology and motility, cell cycle and other cellular functions. IQGAP1 overexpression and delocalization has been observed in several tumors, suggesting a role for this protein in cell proliferation, transformation and invasion. IQGAP1 has been identified as a marker of amplifying cancer cells in GBMs. To determine the involvement of IQGAP1 in the onco-biology of GBM, we performed immunohistochemical confocal microscopic analysis of the IQGAP1 protein in human GBM tissue samples using cell type-specific markers. IQGAP1 immunostaining and subcellular localization was heterogeneous; the protein was located in the plasma membrane and, at variable levels, in nucleus and/or cytosol. Moreover, IQGAP1 positive staining was found in podosome/invadopodia-like structures. IQGAP1+ staining was observed in neurons (Map2+ cells), in cancer stem cells (CSC; nestin+) and in several macrophages (CD31+ or Iba1+). Our results indicate that the IQGAP1 protein is involved in normal cell physiology as well as oncologic processes.
REVIEW | doi:10.20944/preprints202309.1432.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Imaging; Liquid biopsy; glioma; glioblastoma; focused ultrasound; tumor biomarkers
Online: 21 September 2023 (07:24:16 CEST)
Clinical management in neuro-oncology has changed to an integrative approach that incorporates molecular profile alongside histopathology and imaging findings. While the WHO guideline recommends genotyping of informative alterations as a routine clinical practice for central nervous system (CNS) tumors, acquisition of tumor tissue in the CNS is invasive and not always possible. Liquid biopsy is a non-invasive approach that provides the opportunity to capture the complex molecular heterogeneity of the whole tumor through detection of circulating tumor biomarkers in body fluids, such as blood or cerebrospinal fluid. Despite all the advantages, the low abundance of tumor-derived biomarkers, particularly in CNS tumors, as well as their short half-life has limited the application of liquid biopsy in clinical practice. Thus, it is crucial to identify factors that are associated with the presence of these biomarkers and explore possible strategies that can increase the shedding of these tumoral components into biological fluids. In this review, we first describe the clinical applications of liquid biopsy in CNS tumors including its roles in early detection of recurrence and monitoring of treatment response. We then discuss the utilization of imaging in identifying factors that affect the detection of circulating biomarkers as well as how image-guided interventions such as focused ultrasound can help enhance the presence of tumor biomarkers through blood-brain barrier disruption.
ARTICLE | doi:10.20944/preprints202308.0882.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Radiotherapy; Dose Prediction; Deep Learning; Quality Assurance; VMAT; Glioblastoma
Online: 11 August 2023 (08:01:39 CEST)
Background: External beam radiation therapy requires a sophisticated and laborious planning procedure. To improve the efficiency and quality of the planning procedure, machine learning predictions of the dose distributions have been introduced to speed up the planning procedure and to serve as quality assurance. The most recent dose prediction models are based on deep learning U-Nets that give good approximations of the dose in 3D almost instantly. It is our purpose to train a 3D dose prediction for glioblastoma VMAT treatment and test its robustness and sensitivity for the purpose of quality assurance of automatic contouring. Methods: From a cohort of 125 glioblastoma (GBM) patients, VMAT plans were created according to a clinical protocol. The initial model was trained on a concatenated 3D U-Net. A total of 60 cases were used for training, 15 for validation and 20 for testing. The prediction model was tested for sensitivity to dose changes according to realistic contour variations. Additionally, the model was tested for robustness by exposing it to a worst-case test set containing out-of-distribution cases.Results: The initially trained prediction model had a dose score of 0.94 Gy and a mean DVH score for all structures of 1.95 Gy. In terms of sensitivity, the model was able to predict the dose changes that occurred due to the contour variations with a mean error of 1.38 Gy.Conclusions: We obtained a 3D VMAT dose prediction model for GBM with limited data, providing good sensitivity to realistic contour variations. We tested and improved the model's robustness, by targeted updating the training set, making it a useful technique for dose awareness in the contouring evaluation and quality assurance.
ARTICLE | doi:10.20944/preprints202307.0085.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: glioblastoma; early venous filling; arteriovenous shunt; vascular mimicry; Avastin
Online: 3 July 2023 (12:47:58 CEST)
Preoperative angiography in glioblastoma (GBM) often shows arteriovenous shunts and early venous filling (EVF). Here, we investigated the clinical implications of EVF in GBM as a prognostic and vascular mimicry biomarker. In this retrospective multicenter study, we consecutively enrolled patients who underwent angiography with a GBM diagnosis between April 1, 2013, and March 31, 2021. The primary and secondary endpoints were the differences in overall survival (OS) and progression-free survival (PFS), respectively, between cases with and without EVF. Of 133 initially enrolled patients, 91 newly diagnosed with GBM underwent preoperative angi-ography and became the study population. The 6-year OS and PFS were significantly worse in the EVF than in the non-EVF group. Moreover, 20 GBM cases (10 with EVF and 10 without EVF) were randomly selected and evaluated for histological vascular mimicry. Except for two cases that were difficult to evaluate, the EVF group had a significantly higher frequency of vascular mimicry than the non-EVF group (0/8 vs. 5/10, P = 0.04). EVF on preoperative angiography is a robust prognostic biomarker for GBM and may help detect cases with a high frequency of histological vascular mimicry.
BRIEF REPORT | doi:10.20944/preprints202208.0025.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: glioblastoma; extracellular vesicles; Next Generation Sequencing; pathogenic mutations; NF1
Online: 1 August 2022 (15:07:04 CEST)
The biological heterogeneity of glioblastoma (GBM), the most aggressive type of brain cancer, is a critical hallmark, caused by changes in the genomic mutational asset and influencing the clinical progression over the time. The understanding and monitoring of the mutational profile is important not only to reveal novel therapeutic targets in this set of patients, but also to ameliorate the clinical stratification of subjects and the prognostic significance. As neurosurgery represents the primary technique to manage GBM, it is of outmost importance to optimize alternative and less invasive methods to monitor the dynamic mutation profile of these patients. Extracellular vesicles (EV) are included in the liquid biopsy analysis and have emerged as the biological mirror of escaping and surviving mechanisms by many tumors as well as glioblastoma. Very few studies have investigated the technical feasibility to detect and analyze the genomic profile by Next Generation Sequencing (NGS) in circulating EV of patients with grade IV glioblastoma. Here, we attempted to characterize and to compare with the corresponding matched tissue samples, potential variants with pathogenic significance of the DNA contained in peripheral blood derived EV. The NGS analysis has revealed that patients with grade IV glioblastoma, exhibited lesser DNA content in EV than controls and that both in EV and matched cancer tissues, the NF1 gene was consistently mutated in all patients with the c.2568C>G as the most common pathogenic variant expressed. This study supports the clinical utility of the circulating EV in glioblastoma and as eligible tool for personalized medicine.
REVIEW | doi:10.20944/preprints202103.0114.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: organoid; stem cell; cancer; glioblastoma; glioma; oncology; precision medicine
Online: 2 March 2021 (21:59:47 CET)
The emergence of three-dimensional human organoids has opened the door for development of patient-derived cancer organoid (PDO) models, which closely recapitulate parental tumor tissue. Mainstays of preclinical cancer modeling include in vitro cell lines and patient-derived xenografts, but these models lack the cellular heterogeneity seen in human tumors. Moreover, xenograft establishment is resource- and time-intensive, rendering these models difficult to use to inform clinical trials and decisions. PDOs, however, can be created efficiently and retain tumor-specific properties such as cellular heterogeneity, cell-cell and cell-stromal interactions, tumor microenvironment, and therapeutic responsiveness. PDO models and drug screening protocols have been described for several solid tumors and, more recently, for gliomas. Since PDOs can be developed in clinically relevant timeframes and share many characteristics of parent tumors, they may enhance the ability to provide precision oncologic care for patients. This review explores the current literature on cancer organoids, highlighting the history of PDO development, organoid models of glioma, and potential clinical applications of PDOs.
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; miRNA; MGMT; survival; radiotherapy; chemotherapy; temozolomide; translational medicine
Online: 9 April 2020 (08:27:12 CEST)
Glioblastoma multiforme (GBM) is the most common high-grade intracranial tumor in adults. It is characterized by uncontrolled proliferation, diffuse infiltration due to high invasive and migratory capacities, as well as intense resistance to chemo- and radiotherapy. With a five-year survival of less than 3% and an average survival rate of 12 months after diagnosis, GBM has become a focus of current research to urgently develop new therapeutic approaches in order to prolong survival of GBM patients. The methylation status of the promoter region of the O6-methylguanine–DNA methyltransferase (MGMT) is nowadays routinely analyzed, since a methylated promoter region is beneficial for an effective response to temozolomide-based chemotherapy. Furthermore, several miRNAs were identified regulating MGMT expression, apart from promoter methylation, by degrading MGMT mRNA before protein translation. These miRNAs could be a promising innovative treatment approach to enhance Temozolomide (TMZ) sensitivity in MGMT unmethylated patients and to increase progression-free survival as well as long-term survival. In this review, the relevant miRNAs are systematically reviewed.
REVIEW | doi:10.20944/preprints201909.0327.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; renin-angiotensin system; cancer stem cells; drug repurposing
Online: 29 September 2019 (06:21:26 CEST)
Patients with glioblastoma (GB), a highly aggressive brain tumor, have a median survival of 14.6 months following neurosurgical resection with adjuvant chemoradiotherapy. Quiescent GB cancer stem cells (CSCs) invariably cause local recurrence. These GB CSCs that can be identified by embryonic stem cell markers express components of the renin-angiotensin system and are associated with circulating CSCs. Despite the presence of circulating CSCs, GB rarely develops distant metastasis outside the central nervous system. This paper reviews the current literature on GB growth inhibition in relation to CSCs, circulating CSCs, the RAS and the novel therapeutic approach by repurposing drugs that target the renin-angiotensin system to improve overall symptom-free survival and maintain quality of life.
ARTICLE | doi:10.20944/preprints201908.0304.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: glioblastoma; GBM; glioma; STAT3; STAT5A; hsa-miR-181d; microRNA
Online: 29 August 2019 (05:22:29 CEST)
Background: Glioblastoma (GBM), a malignant grade IV tumor, is the most malignant brain tumor due to its hyper-proliferative and apoptosis-evading characteristics. The signal transducer and activators of transcription (STAT) family genes, including STAT3 and STAT5A, have been indicated to play important roles in GBM progression. Increasing number of reports suggest that Garcinol, a polyisoprenylated benzophenone and major bioactive component of Garcinia indica contains potent anti-cancer activities. Material & Methods: The present study investigated the anti-GBM effects of garcinol, focusing on the STAT3/STAT5A activation, using a combination of bioinformatics, in vitro, and ex vivo assays. Results: Our bioinformatics analysis of TCGA - GBM cohort (n=173) showed that STAT3 and STAT5A are preferentially elevated in primary and recurrent GBM, compared to non-tumor brain tissues, and is significantly correlated with reduced overall survival. In support, our immunohistochemical staining of a GBM cohort (n=30) showed an estimated 5.3-fold (p<0.001) elevation in STAT3 and STAT5A protein expression in primary and recurrent GBM versus the non-tumor group. In vitro, garcinol treatment significantly suppressed the proliferative, invasive, and migratory potential of U87MG or GBM8401 cells, dose-dependently. In addition, garcinol anticancer effect significantly attenuated the GBM stem cell-like phenotypes, as reflected by diminished ability of U87MG or GBM8401 to form colonies and tumorspheres and suppressed expression of OCT4 and SOX2. Furthermore, analysis on GBM transcriptome revealed an inverse correlation between the level of STAT3/5A and hsa-miR-181d. Garcinol-mediated anti-GBM effects were associated with an increased hsa-miR-181d/STAT3 and hsa-miR-181d/5A ratio. Conclusion: We present evidence of anti-GBM efficacy of garcinol mediated by enhancing the hsa-miR-181d/STAT3 and hsa-miR-181d/5A ratios in GBM cells. Our findings suggest a potential new therapeutic agent for combating aggressive GBM.
ARTICLE | doi:10.20944/preprints201706.0071.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: 8-prenylnaringenin; naringenin; cellular accumulation; glioblastoma; cytotoxicity; confocal microscopy
Online: 16 June 2017 (03:25:34 CEST)
Gliomas are one of the most aggressive and treatment-resistant types of human cancer. One of the most promising field in gliomas cancer therapy is identification and evaluation of anticancer properties of compounds found in plants i.a. naringenin (N) and 8-prenylnaringenin (8PN). The prenyl group seem to be crucial to the anticancer activity of flavones, which may lead to enhanced cell membrane targeting and thus increased intracellular activity. Unfortunately, 8PN content in hop cones is from 10 to 100 times lower compared to other flavonoids i.e. xanthohumol. In this study we used a simple method for the synthesis of 8PN from isoxanthohumol, via O-demethylation with high, 97% of the isolated yield. Cellular accumulation and cytotoxicity of naringenin and 8-prenylnaringenin in normal (BJ) and cancer cells (U-118 MG) were also examined. Obtained data indicated that 8-prenylnaringenin exhibited higher toxicity against used cell lines than naringenin and both flavones inhibited stronger glioblastoma U-118 MG cells than normal fibroblasts. The anticancer properties of 8PN correlated with its significantly greater (37%), accumulation in glioblastoma cells than in normal fibroblasts. Additionally, naringenin indicated higher selectivity for glioblastoma as it was over 6 times more toxic for cancer than normal cells. Our results provide evidence that examined prenylated and non-prenylated flavanones have different biological activity against normal and cancer cell lines and this phenomenon may be useful in clinical practice to construct new, anticancer drugs for glioblastoma.
REVIEW | doi:10.20944/preprints202309.0711.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Cancer Stem Cell; Androgen Receptor; Prostate Cancer; Breast Cancer; Glioblastoma
Online: 12 September 2023 (03:15:45 CEST)
The cancer stem cell hypothesis suggests that neoplastic cells with stem characteristics hierarchically regulate tumor generation and its high cellular heterogeneity. These cells have been detected in all cancer types, and specific signaling pathways give the regulation of self-renewal and differentiation. In prostate cancer, androgen receptor signaling has been extensively studied, and in non-stem cells, it promotes cell proliferation and tumor progression, but in the cancer stem cell population, it negatively regulates processes such as self-renewal. However, in other types of cancer, such as breast and glioblastoma, the androgen receptor seems to favor the maintenance of cancer stem cells, suggesting that androgen signaling has different effects depending on the tumor context. This review discusses the role of androgen receptor in maintaining cancer stem cells by regulating proliferation, self-renewal, and differentiation, as well as the possible signaling pathways involved in these processes.
ARTICLE | doi:10.20944/preprints202308.1558.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; intranasal delivery; oncolytic adenovirus; XVir‐N‐31; shuttle cells
Online: 22 August 2023 (11:22:58 CEST)
Glioblastoma (GBM) is an aggressive and lethal primary brain tumor with restricted treatment options and a dismal prognosis. Oncolytic virotherapy (OV) has developed as a promising approach for GBM treatment. However, reaching invasive GBM cells may be hindered by tumor-surrounding, non-neoplastic cells when the OV is applied intratumorally. In this study, using a rodent GBM model and immunofluorescence analyses, we investigated the intranasal delivery of the oncolytic adenovirus (OAV) XVir-N-31 via virus-loaded, optimized shuttle cells. Intranasal administration (INA) was selected due to its non-invasive nature and the potential to bypass the blood-brain barrier (BBB). Our findings demonstrate that INA of XVir-N-31 loaded shuttle cells successfully delivers OAVs to the core tumor and invasive GBM cells, significantly prolongs the survival of GBM bearing mice, induces immunogenic cell death and finally reduces tumor burden, all this highlighting the therapeutic potential of this innovative approach. Overall, this study provides compelling evidence for the effectiveness of INA of XVir-N-31 via shuttle cells as a promising therapeutic strategy for GBM. The non-invasive nature of INA of OV-loaded shuttle cells holds great promise for future clinical translation. However, further research is required to assess the efficacy of this approach to ultimately progress in human clinical trials.
ARTICLE | doi:10.20944/preprints202212.0342.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma; blood brain barrier; transforming growth factor beta; NMR metabolomics
Online: 20 December 2022 (01:19:48 CET)
The blood-brain barrier (BBB) is a selectively permeable boundary that separates the circulating blood from the extracellular ﬂuid of the brain and is an essential component for brain homeostasis. In glioblastoma (GBM), the BBB of peritumoral vessels is often disrupted. Pericytes, being important to maintain the BBB integrity, can be functionally modified by GBM cells by inducing proliferation and cell motility via the TGF-β-mediated induction of central epithelial to mesenchymal transition (EMT) factors., We demonstrate that pericytes strengthen the integrity of the BBB in primary endothelial cell/pericyte co-cultures as in vitro BBB model, using TEER measurement of the barrier integrity. In contrast, this effect was abrogated by TGF-β or conditioned medium from TGF-β secreting GBM cells, finally leading to the disruption of a so far intact and tight BBB. TGF-β dramatically changed the metabolic behavior of pericytes, such as shutting down the TCA cycle, driving energy generation from oxidative phosphorylation towards glycolysis, and by shifting the cells towards the activation of pathways that are necessary to produce molecules used for proliferation and cell division. Furthermore, combined metabolomics and RNASeq analyses indicated that the observed functional changes of TGF-β-treated pericytes are closely connected with their behavior.
ARTICLE | doi:10.20944/preprints202202.0051.v1
Subject: Computer Science And Mathematics, Mathematical And Computational Biology Keywords: Glioblastoma; survival prediction; Machine Learning; biomarkers; HumanPSDTM; Long-term survivor
Online: 3 February 2022 (12:00:23 CET)
Glioblastoma (GBM) is a very aggressive malignant brain tumor with the vast majority of patients surviving less than 12 months (Short-term survivors [STS]). Only around 2% of patients survive more than 36 months (Long-term survivors [LTS]). Studying these extreme survival groups might help in better understanding GBM biology. This work aims at exploring application of machine learning methods in predicting survival groups(STS, LTS). We used age and gene expression profiles belonging to 249 samples from publicly available datasets. 10 Machine learning methods have been implemented and compared for their performances. Hyperparameter tuned random forest model performed best with accuracy of 80% (AUC of 74% and F1_score of 85%). The performance of this model is validated on external test data of 16 samples. The model predicted the true survival group for 15 samples achieving an accuracy of 93.75%. This classification model is deployed as a web tool GlioSurvML. The top 1500 features which retained classification efficiency (Accuracy of 80%, AUC of 74%) were studied for enriched pathways and disease-causal biomarker associations using the HumanPSDTM database. We identified 199 genes as possible biomarkers of GBM and/or similar diseases (like Glioma, astrocytoma, and others). 57 of these genes are shown to be differentially expressed across survival groups and/or have impact on survival. This work demonstrates the application of machine learning methods in predicting survival groups of GBM.
REVIEW | doi:10.20944/preprints202105.0007.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Glioblastoma; Oncolytic Virus; Blood Brain Barrier; Tumor Microenvironment; Tumor Heterogeneity
Online: 3 May 2021 (11:01:14 CEST)
Glioblastoma is one of the most difficult tumor types to treat with conventional therapy options like tumor debulking, chemo and radiotherapy. Immunotherapeutic agents like oncolytic viruses, immune checkpoint inhibitors and chimeric antigen receptor T cells have revolutionized cancer therapy, but their success in glioblastoma remains limited and further optimization of immunotherapies is needed. Several oncolytic viruses have demonstrated ability to infect tumors and trigger anti-tumor immune responses in malignant glioma patients. Leading the pack, oncolytic herpesvirus, first in its class, awaits an approval for treating malignant glioma from MHLW, the federal authority of Japan. Nevertheless, some major hurdles like the blood brain barrier, immunosuppressive tumor microenvironment, and tumor heterogeneity can engender suboptimal efficacy in malignant glioma. In this review, we discuss the current status of malignant glioma therapies with a focus on oncolytic viruses in clinical trials. Furthermore, we discuss the obstacles faced by oncolytic viruses in malignant glioma patients and strategies that are being used to overcome these limitations to 1) optimize delivery of oncolytic viruses beyond the blood brain barrier; 2) trigger inflammatory immune responses in and around tumors; and 3) use of multimodal therapies in combination to tackle tumor heterogeneity, with an end goal of optimizing the therapeutic outcome of oncolytic virotherapy.
ARTICLE | doi:10.20944/preprints201810.0697.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioma; glioblastoma; pre-clinical drug development; 3D culture systems; radiotherapy
Online: 30 October 2018 (03:38:28 CET)
Glioblastoma (GBM), the most common and aggressive primary brain tumor in adults, remains one of the least treatable cancers. Current standard of care—combining surgical resection, radiation, and alkylating chemotherapy—results in a median survival of only 15 months. Despite decades of investment and research into the development of new therapies, most candidate anti-glioma compounds fail to translate into effective treatments in clinical trials. One key issue underlying this failure of therapies that work in pre-clinical models to generate meaningful improvement in human patients is the profound mismatch between drug discovery systems—cell cultures and mouse models—and the actual tumors they are supposed to imitate. Indeed, current strategies that evaluate the effects of novel treatments on GBM cells in vitro fail to account for a wide range of factors known to influence tumor growth. These include secreted factors, the brain’s unique extracellular matrix, circulatory structures, the presence of non-tumor brain cells, and nutrient sources available for tumor metabolism. While mouse models provide a more realistic testing ground for potential therapies, they still fail to account for the full complexity of tumor-microenvironment interactions, as well as the role of the immune system. Based on the limitations of current models, researchers have begun to develop and implement novel culture systems that better recapitulate the complex reality of brain tumors growing in situ. A rise in the use of patient derived cells, creative combinations of added growth factors and supplements, may provide a more effective proving ground for the development of novel therapies. This review will summarize and analyze these exciting developments in 3D culturing systems. Special attention will be paid to how they enhance the design and identification of compounds that increase the efficacy of radiotherapy, a bedrock of GBM treatment.
ARTICLE | doi:10.20944/preprints202303.0355.v1
Subject: Arts And Humanities, Literature And Literary Theory Keywords: glioblastoma; biomarker selection; metabolomics; pathway analysis; personalized therapy; network analysis; inflammationomics
Online: 20 March 2023 (09:09:49 CET)
The most aggressive primary malignant brain tumor in adults is glioblastoma (GBM), which has poor overall survival (OS). There is a high relapse rate among patients with GBM despite maxi-mally safe surgery, radiation therapy, temozolomide (TMZ), and aggressive treatment. Hence, there is an urgent and unmet clinical need for new approaches to managing GBM. The current study identified modules (MYC, EGFR, PIK3CA, SUZ12, and SPRK2) involved in GBM disease through the NeDRex plugin. Furthermore, hub genes were identified in a comprehensive interaction network containing 7,560 proteins related to GBM disease and 3,860 proteins associated with signaling pathways involved in GBM. By integrating the results of the aforementioned analyses and performing centrality analysis again, eleven key genes involved in GBM disease were identi-fied. ProteomicsDB or Gliovis databases were used for determining the gene expression in normal or tumor brain tissue. The NetworkAnalyst and the mGWAS-Explorer tools identified miRNAs, SNPs, and metabolites associated with these 11 genes. Moreover, a literature review of recent studies revealed other lists of metabolites related to GBM disease. The enrichment analysis of iden-tified genes, miRNAs, and metabolites associated with GBM disease was done using ExpressAna-lyst, miEAA, and MetaboAnalyst tools. Further investigation of metabolite roles in GBM was done through the pathway, joint pathway, and network analyses. The results of this study identified 11 genes (UBC, HDAC1, CTNNB1, TRIM28, CSNK2A1, RBBP4, TP53, APP, DAB1, PINK1, and RELN), five miRNAs (hsa-mir-221-3p, hsa-mir-30a-5p, hsa-mir-15a-5p, hsa-mir-130a-3p, hsa-let-7b-5p), six metabolites (HDL, N6-acetyl-L-lysine, cholesterol, formate, N, N-dimethylglycine/xylose and X2. piperidinone) and 15 distinct signaling pathways that play an indispensable role in the GBM disease development. To establish early diagnostic methods and plan personalized GBM treatment strategies, the identified top genes-miRNAs and metabolite signatures can be targeted.
ARTICLE | doi:10.20944/preprints202108.0494.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Glioblastoma; immunogenic cell death; innate immunity; natural Killer; macrophages; magnetic hyperthermia
Online: 25 August 2021 (13:45:34 CEST)
Cancer immunotherapies are gaining a large popularity and many of them have been approved as standard second-line or in some cases even as first-line treatment for a wide range of cancers. However, immunotherapy has not shown a clinically relevant success in glioblastoma (GBM), principally due to the brain’s “immune-privileged” status and the peculiar tumor microenvironment (TME) of GBM featured by lack of presence of tumor-infiltrating lymphocytes and the establishment of immunosuppressive mechanisms. Emerging evidence has highlighted the key role played by innate immune cells in immunosurveillance and in initiating and driving immune responses against GBM. Immunogenic cell death (ICD) is a promising approach to elicit direct activation of the innate immune system by inducing in target cancer cells the expression of molecular signatures recognized through a repertoire of innate immune cell pattern recognition receptors (PRRs) by effector innate immune cells. Herein, we explored local mild thermal treatment, generated by using ultrasmall (size ~ 17 nm) cubic-shaped iron oxide nanoparticles exposed to an external alternating magnetic field (AMF), to induce ICD in U87 glioblastoma cells. In accordance with what has been previously observed with other types of tumors, we found that mild hyperthermia modulates the immunological profile of U87 glioblastoma cells by inducing stress-associated signals leading to enhanced phagocytosis and killing of U87 cells by macrophages. Finally, we demonstrated that mild magnetic hyperthermia has a modulatory effect on the expression of inhibitory and activating NK cell ligands on target cells. Interestingly, alteration in the expression of NK ligands, caused by mild hyperthermia treatment, in U87 glioblastoma cells, increased their susceptibility to NK cell killing and NK cell functionality. The overall findings demonstrate that mild magnetic hyperthermia stimulates ICD and sensitizes GBM cells to NK-mediated killing by inducing the upregulation of specific stress ligands, providing a novel immunotherapeutic approach for GBM treatment, with potential to synergize with existing NK cell-based therapies thus improving their therapeutic outcomes.
ARTICLE | doi:10.20944/preprints202012.0789.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: glioblastoma; DCE-MRI; interstitial flow; convection; diffusion; The Cancer Imaging Archive
Online: 31 December 2020 (11:36:28 CET)
Background: Glioblastoma is the deadliest, yet most common, brain tumor in adults, with poor survival and response to aggressive therapy. Therapeutic failure results from a number of causes inherent to these tumors. Imaging, computational, and drug delivery approaches can aid in the quest to access and kill each tumor cell in patients. One factor, interstitial fluid flow, is a driving force therapeutic delivery. However, convective and diffusive transport mechanisms are un-der-studied. In this study, we examine the application of a novel image analysis method to meas-ure fluid flow and diffusion in glioblastoma patients with MRI and compare to patient outcomes. Methods: Building on a prior imaging methodology tested and validated in vitro, in silico and in preclinical models of disease, here we apply our analysis method to archival patient data from the Ivy GAP dataset. Results: We characterize interstitial fluid flow and diffusion patterns in patients. We find strong correlations between flow rates measured within tumors and in the surrounding parenchymal space, where we hypothesized that velocities would be higher. Looking at overall magnitudes, there is significant correlation with both age and survival in this patient cohort. Additionally, we find that tumor size nor resection significantly alter the velocity magnitude. Last, we map the flow pathways in patient tumors and find variability in degree of directionality that we hypothesize in future studies may lead to information concerning treatment, invasive spread, and progression. Conclusions: Analysis of standard DCE-MRI in patients with glioblastoma offers more infor-mation regarding transport within and around tumor, can be measured post-resection and mag-nitudes correlate with patient prognosis.
REVIEW | doi:10.20944/preprints202011.0553.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: brain tumour; satellitosis; tumour heterogeneity; glioblastoma; perineuronal satellitosis; perivascular satellitosis; invasion
Online: 21 November 2020 (08:41:01 CET)
The secondary structures of Scherer commonly known as perineuronal and perivascular satellitosis have been identified as a histopathological hallmark of diffuse, invasive, high-grade gliomas. They are recognized as perineuronal satellitosis when clusters of neoplastic glial cells surround neurons cell bodies and perivascular satellitosis when such tumour cells surround blood vessels infiltrating Virchow-Robin spaces. In this review, we provide an overview of emerging knowledge regarding how interactions between neurons and glioma cells can modulate tumour evolution and how neurons play a key role in glioma growth and progression, as well as the role of perivascular satellitosis into mechanisms of glioma cells spread. At the same time, we review the current knowledge about the role of perineuronal satellitosis and perivascular satellitosis within the tumour microenvironment (TME), in order to highlight critical knowledge gaps in research space.
ARTICLE | doi:10.20944/preprints201912.0382.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: glioblastoma multiforme; MGMT; IDH1; EGFR; P53; ATRX; Ki67; neurosurgery; oncology; epilepsy
Online: 29 December 2019 (13:04:12 CET)
Glioblastoma is a solid, infiltrating and the most frequent highly malignant primary brain tumor. Our aim was to find the prognostic value of mutations of IDH1, MGMT, EGFR, p53, ATRX, Ki67 genes and the correlation between sex, age, presenting with seizures, number of interventions, extent of resection with Overall Survival (OS), Progression Free Survival (PFS) and Karnofsky performance status (KPS) score. A randomized retrospective analysis of 122 patients treated by a single operator at Sapienza University of Rome, was carried out. After surgery patients followed standard treatment Stupp protocol . Exclusion criteria were: patients with primitive brainstem and spinal cord gliomas and patients who underwent partial resections (resection < 90%) and cases of brain biopsy exclusively for diagnostic purposes. Statistical analysis with a simultaneous regression model was carried on by SPSS 25 ® (IBM) program. Results showed statistically significant survival increase in four groups: 1) patients treated with gross total resection (p< 0.03); 2) patients with methylated MGMT promoter (p<0.005); 3) patients with non EGFR amplification or EGFRvIII mutation (p<0.035); 4) mutated IDH1/IDH2 (p<0.0161). Higher survival rates (but not statistically significant) were observed also in patients with: age < 75 years, Ki 67 <10%, lesions in non eloquent areas, ATRX gene mutation and presentation with seizures.
ARTICLE | doi:10.20944/preprints201912.0293.v2
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: radiotherapy; glioblastoma; membrane Hsp70; dose- and time-kinetics; NK cell-based therapy
Online: 27 March 2020 (02:12:22 CET)
The major stress-inducible Hsp70 (HSPA1A) is overexpressed in the cytosol of many highly aggressive tumor cells including glioblastoma multiforme and presented on their plasma membrane. Depending on its intracellular or membrane localization, Hsp70 either promotes tumor growth or serves as a target for NK cells. The kinetics of the membrane Hsp70 (mHsp70) density on human glioma cells (U87) was studied after different irradiation doses to define the optimal therapeutic window for Hsp70-targeting NK cells. To maintain the cells in the exponential growth phase during a cultivation period of 7 days different initial cell counts were seeded. Although cytosolic Hsp70 levels remained unchanged on days 4 and 7 after a sublethal irradiation with 2 Gy, 4 Gy and 6 Gy, a dose of 2 Gy resulted in an upregulated mHsp70 density in U87 cells which peaks on day 4 and starts to decline on day 7. Higher radiation doses (4 Gy, 6 Gy) resulted in an earlier and more rapid onset of the mHsp70 expression on days 2 and 1, respectively, followed by a decline on day 5. Membrane Hsp70 levels are higher in G2/M than in G1, however, an irradiation-induced cell cycle arrest on days 4 and 7, was not associated with an increase in the mHsp70 density. Extracellular Hsp70 concentrations increased significantly compared to sham (0 Gy) irradiated cells on days 4 and 7 but not on day 1. Functionally, elevated mHsp70 densities were associated with a significantly better lysis by Hsp70-targeting NK cells. In summary, the kinetics of changes in the mHsp70 density upon irradiation on tumor cells is time- and dose-dependent.
ARTICLE | doi:10.20944/preprints201908.0124.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: plasmonics; nanomedicine; theranostics; copper; VEGF; glioblastoma; differentiated neuroblastoma; peptidomimetics; qPCR; actin.
Online: 11 August 2019 (07:13:00 CEST)
Angiogenin (ANG), an endogenous protein that plays a key role in cell growth and survival, has been scrutinised here as promising nanomedicine tool for the modulation of pro-/ anti-angiogenic processes in brain cancer therapy. Specifically, peptide fragments from the putative cell membrane binding domain (residues 60-68) of the protein were used in this study to obtain peptide-functionalised spherical gold nanoparticles (AuNPs) of about 10 nm and 30 nm in optical and hydrodynamic size, respectively. Different hybrid biointerfaces were fabricated by peptide physical adsorption (Ang60-68) or chemisorption (the cysteine analogous Ang60-68Cys) at the metal nanoparticle surface, and the cellular assays were performed in the comparison with ANG-functionalised AuNPs. Cellular treatments were performed both in basal and in copper-supplemented cell culture medium, to scrutinise the synergic effect of the metal, which is another known angiogenic factor. Two brain cell lines were investigated in parallel, namely tumour glioblastoma (A172) and neuron-like differentiated neuroblastoma (d-SH-SY5Y). Results on cell viability/proliferation, cytoskeleton actin, angiogenin translocation and VEGF release pointed to the promising potentialities of the developed systems as anti-angiogenic tunable nanoplaftforms in cancer cells treatment.
CONCEPT PAPER | doi:10.20944/preprints201809.0209.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: ADZT regimen; apremilast; bevacizumab; cAMP; dapsone; glioblastoma; telmisartan; TNF-alpha; zonisamide
Online: 12 September 2018 (03:54:33 CEST)
During glioblastoma treatment, the pharmaceutical monoclonal antibody to VEGF, bevacizumab, has improved quality of life and delayed progression for several months but has not, or only marginally prolonged overall survival. In 2017 several dramatic research papers appeared that are crucial to our understanding of glioblastoma vis a vis the mode of action of bevacizumab. As a consequence of these papers, a new, potentially more effective, treatment protocol can be built around bevacizumab. This is the ADZT Regimen where four old drugs are added to bevacizumab. These four are apremilast, marketed to treat psoriasis, dapsone, marketed to treat Hansen’s disease, zonisamide, marketed to treat seizures, and telmisartan, marketed to treat hypertension. The ancillary attributes of each of these drugs has been shown to augment bevacizumab. This paper will detail the research data supporting that contention.
ARTICLE | doi:10.20944/preprints202307.0204.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: deuterium depletion; deuterium-depleted water (DDW); glioblastoma multiforme; median survival time (MST)
Online: 5 July 2023 (03:25:21 CEST)
Glioblastoma multiforme (GBM) and malignant gliomas are the most common primary malignant brain tumors. Temozolomide (TMZ) chemotherapy plus radiation therapy (RT), admi-nistered after debulking surgery, increased median survival time (MST) from 12.1 months with RT alone merely to 14.6 months. In this study, the action of deuterium-depleted water (DDW) on the survival of GBM patients who also received conventional therapies was investigated. Without changing the conventional treatment, the daily fluid intake of the patients was wholly replaced with DDW in 1.5-2 liters per day volume to reduce D concentration in their bodies. The primary endpoint was MST. The 55 patients involved, receiving conventional treatment and consuming DDW, showed longer MST (30 months) compared to the historical control (12.1-14.6 months). There was a massive difference between the two genders in the calculated MST values; it was 25 months in the male subgroup (n=33) and 42 months in the female subgroup (n=22). MST was 27 months without TMZ treatment (38 patients) and 42 months in the TMZ-treated group (17 patients). For the selected 31 patients, who consumed DDW in the correct way in addition to conventional treatments, MST was 30 months. Within this group, the 20 subjects who had relapsed before DDW treatment had 30 months of MST, but in those 10 subjects who were in remission when DDW treatment started, MST was 47 months. In the subgroup of patients who started DDW treatment parallel with radiotherapy, MST was 47 months again, and it was 25 months when DDW treatment started 8 weeks or later after the completion of radiotherapy. Altogether, survival times were substantially prolonged, compared to prospective clinical data of patients with primary GBM. Consequently, if conventional therapies are supplemented with D depletion, better survival is achieved in advanced stage of GBM than with the known targeted or combination therapies. Application of DDW is recommended in all stages of the disease, before surgery, parallel with radiotherapy, and repeated DDW courses are advised when remission has been achieved.
ARTICLE | doi:10.20944/preprints202301.0585.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: glioblastoma; cancer stem cells; EMT; MGMT; temozolomide; doxorubicin; STAT3; EGFR inhibitor (AG1478)
Online: 31 January 2023 (12:01:04 CET)
Glioblastomas (GBM) are most common, primary brain tumors in adults. Despite advances in neurosurgery, radio- and chemotherapy, the median survival of GBM patients is 15 months. Recent large-scale genomic, transcriptomic and epigenetic analyses have shown the cellular and molecular heterogeneity of GBMs, which hampers the outcomes of standard therapies. We have established 13 GBM-derived cell cultures from fresh tumor specimens and characterized them molecularly using RNAseq, immunoblotting and immunocytochemistry. Evaluation of proneural (OLIG2, IDH1R132H, TP53 and PDGFRα), classical (EGFR) and mesenchymal markers (CHI3L1/YKL40, CD44 and phospho-STAT3), as well as expression of pluripotency (SOX2, OLIG2, NESTIN) and differentiation (GFAP, MAP2, β-Tubulin III) markers revealed the striking inter-tumor heterogeneity of primary GBM cell cultures. Upregulated expression of VIMENTIN, N-CADHERIN and CD44 at mRNA/protein levels suggested increased epithelial to mesenchymal transition (EMT) in most studied cell cultures. The effects of temozolomide (TMZ) or doxorubicin (DOX) were tested in three GBM-derived cell cultures with different methylation status of the MGMT promoter. Amongst TMZ- or DOX-treated cultures the strongest accumulation of apoptotic markers: caspase 7 and PARP were found in WG4 cells with methylated MGMT suggesting that its methylation status predicts vulnerability to both drugs. As many GBM-derived cells showed high EGFR levels, we tested the effects of AG1478, an EGFR inhibitor, on downstream signaling pathways. AG1478 caused decreased levels of phospho-STAT3, thus inhibition of active STAT3 augmented antitumor effects of DOX and TMZ in cells with methylated and intermediate status of MGMT. Altogether, our findings show that GBM-derived cell cultures mimic the considerable tumor heterogeneity and identifying patient-specific signaling vulnerabilities can assist in overcoming therapy resistance, by providing personalized combinatorial treatment recommendations.
REVIEW | doi:10.20944/preprints202212.0207.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Blood-Brain Barrier; Brain Drug Delivery; Carbon Nanomaterials; Cerebral Gliomas; Glioblastoma; Nanoparticles.
Online: 12 December 2022 (14:56:45 CET)
Malignant gliomas are the most common primary brain tumors in adults up to an extent of 78% of all primary malignant brain tumors. However, total surgical resection is almost unachievable due to considerable infiltrative ability of glial cells. The efficacy of current multimodal therapeutic strategies is, furthermore, limited by the lack of specific therapies against malignant cells, and, therefore, the prognosis these in patients is still very unfavorable. The limitation of conventional therapies, which may result from inefficient delivery of the therapeutic or contrast agent to brain tumors are major reasons for this unsolved clinical problem. The major problem in brain drug delivery is the presence of the blood brain barrier which limits the delivery of many chemotherapeutic agents. Nanoparticles, thanks to their chemical configuration, are able to go through the blood-brain barrier carrying drugs or genes targeted against gliomas. Carbon nanomaterials show distinct properties including electronic properties, penetrating capability on the cell membrane, high drug-loading and pH-dependent therapeutic unloading capacities, thermal properties, large surface area and easy modification with molecules, which render them as a suitable candidate to deliver drugs. In this review we will focus on the potential effectiveness of the use of carbon nanomaterials in the treatment of malignant gliomas discussing the current progress of in vitro and in vivo researches of carbon nanomaterials-based drug delivery to brain.
ARTICLE | doi:10.20944/preprints202212.0170.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: SonoCloud; GL261 mouse model; ultrasound-mediated drug delivery; glioblastoma; immune checkpoint inhibitors
Online: 9 December 2022 (02:59:28 CET)
Therapeutic antibodies targeting immune checkpoints have shown limited efficacy in clinical trials in glioblastoma (GBM) patients. Ultrasound-mediated blood-brain barrier opening (UMBO) using low-intensity pulsed ultrasound improved drug delivery to the brain. We explored the safety and the efficacy of UMBO plus immune checkpoint inhibitors in preclinical models of GBM. A Blood-brain barrier (BBB) opening was performed using a 1 MHz preclinical ultrasound system in combination with 10µl/g microbubbles. Brain penetration of immune checkpoint inhibitors was determined, and immune cell populations were evaluated using flow cytometry. The impact of repeated treatments on survival was determined. In syngeneic GL261-bearing immunocompetent mice, we showed that UMBO safely and repeatedly open the BBB. BBB opening was confirmed visually and microscopically using Evans’s blue dye and magnetic resonance imaging. UMBO plus anti-PDL-1 was associated with a significant improvement of the overall survival compared to anti-PD-L1 alone. Using mass spectroscopy, we showed that the penetration of therapeutic antibodies can be increased when delivered intravenously compared to non-sonicated brains. Furthermore, we observed an enhancement of activated microglia percentage when combined with anti-PD-L1. Here, we report that the combination of UMBO and anti-PD-L1 dramatically increases GL261-bearing mice's survival compared to their counterparts treated with anti-PD-L1 alone. Our study highlights the BBB as a limitation to overcome to increase the efficacy of anti-PD-L1 in GBM and supports clinical trials combining UMBO and in GBM patients.
ARTICLE | doi:10.20944/preprints202205.0142.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; immunotherapy; radiotherapy; brain cancers; radioimmunotherapy; immune checkpoint inhibitors; temozolomide; durvalumab; immunoradiotherapy.
Online: 10 May 2022 (13:22:16 CEST)
Glioblastoma (GBM) is the most common primary brain tumor. Due to high resistance to treatment, local invasion, and high risk of recurrence, GBM patient prognoses are often dismal, with median survival around 15 months. The current standard of care is threefold: surgery, radiation therapy and chemotherapy with temozolomide (TMZ). However, patient survival has only marginally improved. Radioimmunotherapy (RIT) is a fourth modality under clinical trials and aims at combining immunotherapeutic agents with radiotherapy. Here, we develop in vitro assays for rapid evaluation of RIT strategies. Using a standard cell irradiator and an Electric Cell Impedance Sensor, we quantify cell migration following the combination of radiotherapy and chemotherapy with TMZ and RIT with durvalumab, a PD-L1 immune checkpoint inhibitor. We measure cell survival using a cloud-based clonogenic assay. Irradiated T98G and U87 GBM cells migrate significantly (p < 0.05) more than untreated cells in the first 20-40 hours post-treatment. Addition of TMZ increased migration rates for T98G at the 20 Gy (p < 0.01). Neither TMZ nor durvalumab significantly changed cell survival in 21 days post-treatment. Interestingly, durvalumab abolished the enhanced migration effect, indicating possible potency against local invasion. These results provide parameters for rapid supplementary evaluation of RIT against brain tumors.
ARTICLE | doi:10.20944/preprints202310.1809.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Glioblastoma Multoforme; Immunoregulation; PGLS; Gene Enrichment; Immune Cell Infiltration; Hsa-mir-380-5p
Online: 27 October 2023 (13:22:38 CEST)
Aim: Glioblastoma multiform (GBM) is a prevalent brain cancer which accounts for 80% of cases globally with a noticeably short life expectancy subsequent diagnosis. There are several factors associated with GBM including alterations and over expressions of oncoproteins. Analysis of SEC61G expression in GBM patient’s favor tumour progression, which promotes an environment of oxidative stress, while preventing apoptosis. Methods: In this article using in silico tools including GEPIA2, ULCAN, LinkedOmics, Gene MANIA and mirTEd, we observed the role of SEC61G gene in GBM progression by analyzing the expression, positive correlation associated with metabolic, mitochondrial gene, immune cell infiltration level, gene interaction networks, miRNA association as well as survival analysis. Results: The expression of the mitochondrial, metabolic genes PGLS, PGK1, EIF6, and EIF3K which are involved in redox metabolism and CD63 immunoregulation, as well as other genes that promote tumour progression and invasion, including EGFR, LANCL2, BCL2L12, SEC61G-DT, KDELR1, CDKN2A, IFNA16, IFNA10, and BCL7C were positively correlated with the increased/high expression of SEC61G.We also found hsa-mir-380-5p to be unregulated in glioblastoma phenotypes. Conclusion: Our findings suggest that SEC61G associated redox metabolism, complement system and immunoregulation, as well as miRNA expression can be targeted to develop a potential therapeutic approach for GBM patients.
ARTICLE | doi:10.20944/preprints202309.1355.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma; Magnetic Resonance Imaging; Treatment response assessment; Treatment follow-up; Pseudoprogression; Perfusion Imaging
Online: 20 September 2023 (10:47:56 CEST)
MRI is the gold standard for treatment response assessment in glioblastoma. However, there is no consensus regarding the optimal interval for MRI follow-up during standard treatment. Moreover, reliable assessment of treatment response is hindered by the occurrence of pseudoprogression. It is unknown if a radiological follow-up strategy with 2-3 months intervals actually benefits patients and how it influences clinical decision making about continuation or discontinuation of treatment. This study assessed the consequences of scheduled follow-up scans (post-chemoradiotherapy [post-CCRT], after 3 cycles of adjuvant chemotherapy [TMZ3/6], after completion of treatment [TMZ6/6]) and unscheduled scans on treatment decisions during standard concomitant and adjuvant treatment in glioblastoma patients. Additionally, we evaluated how often follow-up scans resulted in diagnostic uncertainty (tumor progression versus pseudoprogression), and whether perfusion MRI improved clinical decision making. Scheduled follow-up scans during standard treatment in glioblastoma patients rarely resulted in early termination of treatment (2.3% post-CCRT, 3.2% TMZ3/6, and 7.8% TMZ6/6), but introduced diagnostic uncertainty in 27.7% of cases. Unscheduled scans resulted in more major treatment consequences (30%; p<0.001). Perfusion MRI caused less diagnostic uncertainty (p=0.021) but did not influence treatment consequences (p=0.871). This study does not support the current pragmatic follow-up strategy and suggests a more tailored follow-up approach.
REVIEW | doi:10.20944/preprints202212.0363.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Liquid biopsy; glioblastoma; GBM; cfDNA; ctDNA; brain tumor; MRD; monitoring; CTC; treatment response
Online: 20 December 2022 (09:00:47 CET)
Glioblastoma is the most common and malignant primary brain tumor. Despite a century of research efforts, the survival of patients has not significantly improved. Currently, diagnosis is based on neuroimaging techniques followed by histopathological and molecular analysis of resected or biopsied tissue. A recent paradigm shift in diagnostics ranks the molecular analysis of tissue samples as the new gold standard over classical histopathology, thus correlating better with the biological behavior of glioblastoma and clinical prediction, especially when a tumor lacks the typical hallmarks for glioblastoma. Liquid biopsy aims to detect and quantify tumor-derived content, such as nucleic acids (DNA/RNA), circulating tumor cells (CTC), or extracellular vesicles (EV) in biofluids, mainly blood, cerebrospinal fluid (CSF), or urine. Liquid biopsy has the potential to overcome the limitations of both neuroimaging and tissue-based methods to identify early recurrence and to differentiate tumor progression from pseudoprogression, without the risks of repeated surgical biopsies. This review highlights the origins and time-frame of liquid biopsy in glioblastoma and points to recent developments, limitations and challenges of adding liquid biopsy to support the clinical management of glioblastoma patients.
CONCEPT PAPER | doi:10.20944/preprints201810.0689.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: 5-aminolevulinic acid, ciprofloxacin, deferiprone, fluorescence, 5-fluorouracil, febuxostat, glioblastoma, photodynamic treatment, temozolomide,
Online: 29 October 2018 (14:12:07 CET)
The CAALA (Complex Augmentation of ALA) regimen was developed with the goal of redressing some of the weaknesses of 5-aminolevulinic acid (5-ALA) use in glioblastoma treatment as it now stands. 5-ALA is approved for use prior to glioblastoma surgery to better demarcate tumor from brain tissue. 5-ALA is also used in intraoperative photodynamic treatment of glioblastoma by virtue of uptake of 5-ALA and its selective conversion to protoporphyrin IX in glioblastoma cells. Protoporphyrin IX becomes cytotoxic after exposure to 410 nm or 635 nm light. CAALA uses four currently marketed drugs - the antibiotic ciprofloxacin, the iron chelator deferiprone, the antimetabolite 5-FU, and the xanthine oxidase inhibitor febuxostat - that all have evidence of ability to both increase 5-ALA mediated intraoperative glioblastoma demarcation and photodynamic cytotoxicity of in situ glioblastoma cells. Data from testing the full CAALA on living minipigs xenotransplanted with human glioblastoma cells will determine safety and potential for benefit in advancing CAALA to a clinical trial.
ARTICLE | doi:10.20944/preprints202203.0125.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: ATP synthase; cancer cell; mitochondria; glioblastoma; integrin αvβ3; NADH dehydro-genase; tetrac; thyroid hormones
Online: 9 March 2022 (01:55:26 CET)
Chemically modified forms of tetraiodothyroacetic acid (tetrac), an L-thyroxine derivative, have been shown to exert their anticancer activity at plasma membrane integrin αvβ3 of tumor cells. Via a specific hormone receptor on the integrin, tetrac-based therapeutic agents modulate expression of genes relevant to cancer cell proliferation, survival and energy metabolism. P-bi-TAT, a novel bivalent tetrac-containing synthetic compound has anticancer activity in vitro and in vivo against Glioblastoma Multiforme (GBM) and other types of human cancers. In the current study, microarray analysis was carried out on a primary culture of human GBM cells exposed to P-bi-TAT (10-6 tetrac equivalent) for 24 h. P-bi-TAT significantly affected expression of a large panel of genes implicated in cancer cell stemness, growth, survival, and angiogenesis. Recent interest elsewhere in ATP synthase as a target in GBM cells caused us to focus attention on expression of genes involved in energy metabolism. Significantly downregulated transcripts included multiple energy metabolism-related genes: electron transport chain genes ATP5A1 (ATP synthase 1), ATP51, ATP5G2, COX6B1 (cytochrome c oxidase subunit 6B1), NDUFA8 (NADH dehydrogenase [ubiquinone] FA8), NDUFV2I and other NDUF genes. The NDUF and ATP genes are also relevant to control of oxidative phosphorylation and transcription. Qualitatively similar actions of P-bi-TAT on expression of energy metabolism-linked genes were also detected in established human GBM and pancreatic cancer cell lines. In conclusion, acting at αvβ3 integrin, P-bi-TAT caused downregulation in human cancer cells of expression of a large number of genes involved in electron transport and oxidative phosphorylation. These observations suggest that cell surface thyroid hormone receptors on αvβ3 regulate expression of genes relevant to tumor cell stemness and energy metabolism.
ARTICLE | doi:10.20944/preprints202012.0166.v1
Subject: Computer Science And Mathematics, Algebra And Number Theory Keywords: Mathematical oncology; CAR-T cells; mathematical immunology; mathematical modelling; immunotherapy of solid tumours; glioblastoma
Online: 7 December 2020 (15:06:37 CET)
Chimeric antigen receptor (CAR)-T cell-based therapies have achieved substantial successes against B-cell malignancies, what has led to a growing scientific and clinical interest on extending their use to solid cancers. However, results for solid tumours have been limited up to now, in part due to the immuno-suppressive tumour microenvironment, that is able to inactivate CAR-T cell clones. In this paper we put forward a mathematical model describing the competition of CAR-T and tumour cells, accounting for their immunosuppressive capabilities. Using the mathematical model, we show that the use of large numbers of CAR-T cells targeting the solid tumour antigens could overcome the cancer immunosuppressive potential. To achieve such high levels of CAR-T cells we propose and study computationaly, the manufacture and injection of CAR-T cells targeting two antigens: CD19 and a tumour-associated antigen. We study in-silico the resulting dynamics of the disease after the injection of this product and find that the expansion of the CAR-T cell population in the blood and lymphopoietic organs could lead to the massive generation of an army of CAR-T cells targetting the solid tumour, and potentially overcoming its inmune suppression capabilities. That strategy could benefit from the combination with PD-1 inhibitors and of low tumour loads. Our computational results provide a theoretical support for the treatment of different types of solid tumours using T-cells engineered with combination treatments of dual CARs with on- and off-tumour activity and anti-PD1 drugs after completion of classical cytoreductive treatments.
ARTICLE | doi:10.20944/preprints202310.1912.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: Glioblastoma; cancer stem cells; M2 muscarinic receptor; orthosteric and dualsteric muscarinic agonism; autophagy; apoptosis; mTORC1
Online: 30 October 2023 (13:57:53 CET)
Background: Although autophagy is a pro-survival process of tumor cells, in particular conditions and when differently regulated by specific signals it can stimulate cell death. We previously demonstrated that the selective stimulation of the M2 muscarinic receptor subtype (M2 mAChR) negatively controls cell proliferation and survival and causes oxidative stress and cytotoxic and genotoxic effects in both GBM cell lines and GBM stem cells (GSCs). In this work, we have evaluated whether autophagy was induced as a downstream mechanism of the observed cytotoxic processes induced by M2 mAChR activation by the orthosteric agonist APE or the dualsteric agonist N-8-Iper. Methods: To assess the activation of autophagy, we analyzed the expression of LC3B by Western blot analysis and in LC3B-EGFP transfected cell lines. Apoptosis was assessed by Caspases 3 and 9 protein expression. Results: Our data indicate that activation of M2 mAChR by N-8-Iper promotes autophagy in both U251 and GB7 cells lines as suggested by the LC3B-II expression level and analysis of the transfected cells by fluorescence microscopy. Autophagy induction by M2 mAChRs is regulated by the decreased activity of the PI3K/AKT/mTORC1 pathway and upregulated by the pAMPK expression. Downstream autophagy activation, the increase of apoptosis was also observed in both cell lines after treatment with the two M2 agonists. Conclusions: N-8-Iper treatment causes autophagy via pAMPK upregulation, followed by apoptosis in both investigated cell lines. In contrast, the absence of autophagy in APE-treated GSC cells seems to indicate that cell death could be triggered by mechanisms alternative to those observed for N-8-Iper.
ARTICLE | doi:10.20944/preprints202308.1756.v2
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: PDPN; lung cancer; glioblastoma; monoclonal antibody; antitumor activities; mouse xenograft model; antibody-dependent cellular cytotoxicity
Online: 20 October 2023 (12:26:35 CEST)
We previously developed a highly sensitive and specific anti-PDPN mAb, LpMab-23 (mouse IgG1, kappa). In this study, we produced a humanized IgG1 version (humLpMab-23) and its defucosylated form (humLpMab-23-f) of an anti‑PDPN mAb to potentiate the ADCC activity. The humLpMab-23 could recognize PDPN‑overexpressed Chinese hamster ovary (CHO)-K1 (CHO/PDPN) and PDPN-positive PC-10 and LN319 cells by flow cytometry. Furthermore, we found that humLpMab-23-f exerted ADCC and complement-dependent cytotoxicity against CHO/PDPN, PC-10 and LN319 cells in vitro and exhibited potent antitumor activities in the xenograft models. These results indicated that humLpMab-23-f could be useful for an antibody treatment regimen for PDPN-positive human cancers.
REVIEW | doi:10.20944/preprints202307.1897.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Keywords： recurrent glioblastoma; immunotherapy; CAR-T therapy; immune checkpoint inhibitor; cancer vaccine; oncolytic viral therapy
Online: 27 July 2023 (09:30:30 CEST)
ABSTRACT: Recurrent glioblastoma (rGBM) is a highly aggressive form of brain cancer that poses a significant challenge for treatment in neurooncology, and the survival status of patients after relapse usually means rapid deterioration, and also the leading cause of death among patients. In recent years, immunotherapy has emerged as a promising strategy for the treatment of recurrent glioblastoma by stimulate the body's immune system to recognize and attack cancer cells , which could be used as a in combination with other treatments such as surgery, radiation, and chemotherapy to improve outcomes for patients with recurrent glioblastoma, This therapy combines several key methods such as the use of monoclonal antibodies, chimeric antigen receptor T cell (CAR-T) therapy, checkpoint inhibitors, oncolytic viral therapy cancer vaccines, and combination strategies. In this review, we mainly document the latest immunotherapies for the treatment of glioblastoma and focus on the rGBM especially.
REVIEW | doi:10.20944/preprints202103.0783.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: ursolic acid; oleanolic acid; neuroprotection; ischaemia; neurodegeneration; Alzheimer’s disease; Parkinson’s disease; neuro-inflammation; cancer; glioblastoma
Online: 31 March 2021 (16:17:04 CEST)
Ursolic and oleanolic acids are secondary plant metabolites that are known to be involved in the plant defence system against water loss and pathogens. Nowadays these triterpenoids are also regarded as potential pharmaceutical compounds and there is mounting experimental data that either purified compounds or triterpenoid-enriched plant extracts exert various beneficial effects, including anti-oxidative, anti-inflammatory and anticancer, on model systems of both human or animal origin. Some of those effects have been linked to the ability of ursolic and oleanolic acids to modulate intracellular antioxidant systems and also inflammation- and cell death-related pathways. Therefore, our aim was to review the current knowledge about the distribution of ursolic and oleanolic acids in plants, bioavailability and pharmacokinetic properties of these triterpenoids and their derivatives, and to discuss their neuromodulatory effects in vitro and in vivo.
ARTICLE | doi:10.20944/preprints201908.0288.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: array-comparative genomic; gliomas; Cell culture; Cancer genomics; Cancer Transcriptomics; brain tumors; cell line; glioblastoma
Online: 27 August 2019 (16:34:22 CEST)
Cancer cell lines are widely used as in vitro models of tumorigenesis, facilitating fundamental discoveries in cancer biology and translational medicine. Currently, there are few options for glioblastoma (GBM) treatment and limited in vitro models with accurate genomic and transcriptomic characterization. Here, a detailed characterization of a new GBM cell line, namely AHOL1, was conducted in order to fully characterize its molecular composition based on its copy number alteration (CNA) and transcriptome profiling, followed by the validation of key elements associated with GBM tumorigenesis. Large numbers of CNAs and differentially expressed genes (DEGs) were identified. CNAs were distributed throughout the genome, including gains at Xq11.1-q28, Xp22.33-p11.1, Xq21.1-q21.33, 4p15.1-p14, 8q23.2-q23.3 and losses at Yq11.21-q12, Yp11.31-p11.2 and 12p13.31 positions. Nine druggable genes were identified, including HCRTR2, ETV1, PTPRD, PRKX, STS, RPS6KA6, ZFY, USP9Y and KDM5D. By integrating DEGs and CNAs, we identified 57 overlapping genes enriched in fourteen pathways. Altered expression of several cancer-related candidates found in the DEGs-CNA dataset was confirmed by RT-qPCR. Taken together, this first comprehensive genomic and transcriptomic landscape of AHOL1 provides unique resources for further studies and identifies several druggable targets that may be useful for therapeutics and biologic and molecular investigation of GBM.
ARTICLE | doi:10.20944/preprints202306.1963.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma Multiform (GBM); Cancer Stem Cella (CSC); Molecular Dynamics Simulation; In-silico; Phytochemical Screening; FOXM1; ADMET
Online: 28 June 2023 (08:23:27 CEST)
Glioblastoma multiforme (GBM) is a highly heterogeneous brain tumor with limited treatment options and a poor prognosis. Cancer stem cells (CSCs) have emerged as a critical factor in GBM resistance and management, contributing to tumor growth, heterogeneity, and immunosuppression. The transcription factor FOXM1 has been identified as a key player in the progression, spread, and therapy resistance of various cancers, including GBM. In this study, researchers conducted structure-based in silico screening to identify natural compounds that could target the DNA-binding domain (DBD) of the FOXM1 protein. Through molecular docking analyses, identified Silybin B as a potential inhibitor of FOXM1, exhibiting strong interaction with the protein. MD simulations were performed to validate the binding stability of the FOXM1-Silybin B complex. The study provides valuable insights into the potential of Silybin B as a FOXM1 inhibitor and its ability to induce senescence in GBM stem cells. These findings contribute to the development of structure-based design strategies for FOXM1 inhibitors and innovative therapeutic approaches for the treatment of Glioblastoma.
ARTICLE | doi:10.20944/preprints202212.0442.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: P21; CDKN1A; glioblastoma; senescence; cancer senescence; gene overexpression; gene knock-in; CRISPR/Cas9; dCas; dCas-VPR
Online: 23 December 2022 (04:10:22 CET)
High-grade gliomas are the most common and aggressive adult primary brain tumors with a median survival of only 12-15 months. Current standard therapy consists of maximal safe surgical resection followed by DNA-damaging agents, such as irradiation and chemotherapy that can delay but not prevent inevitable recurrence. Some have interpreted glioma recurrence as evidence of glioma stem cells which persist in a relatively quiescent state after irradiation and chemotherapy, before the ultimate cell cycle re-entry and glioma recurrence. Conversely, latent cancer cells with a therapy-induced senescent phenotype have been shown to escape senescence, giving rise to more aggressive stem-like tumor cells than those present in the original tumor. Therefore, approaches are needed to either eliminate or keep these glioma-initiating cells in a senescent state for a longer time to prolong survival. In our current study, we demonstrate that the radiation-induced cell cycle inhibitor P21 can provide a powerful route to induce cell death in short-term explants of PDXs derived from three molecularly diverse human gliomas. Additionally, cells not killed by P21 overexpression were maintained in a stable senescent state for longer than control cells. Collectively, these data suggest that P21 activation may provide an attractive therapeutic target to improve therapeutic outcomes.
ARTICLE | doi:10.20944/preprints202203.0060.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: carnosine; glioblastoma; fibroblasts; imidazole-containing compounds; cell viability; high per-formance liquid chromatography coupled mass spectrometry
Online: 3 March 2022 (10:31:32 CET)
The naturally occurring dipeptide carnosine (β alanyl L histidine) specifically attenuates tumor growth. Here, we asked whether other small imidazole containing compounds also affect viability of tumor cells without affecting non-malignant cells, and whether formation of histamine is involved. Patient-derived fibroblasts and glioblastoma cells were treated with carnosine, L alanyl L histidine (LA-LH), ß alanyl L alanine, L histidine, histamine, imidazole, β alanine and L alanine. Cell viability was assessed by cell-based assays and microscopy. The intracellular release of L histidine and formation of histamine was investigated by High Performance Liquid Chromatography coupled Mass Spectrometry. Whereas carnosine and LA LH inhibited tumor cell growth with minor effects on fibroblasts, L-histidine, histamine and imidazole affected viability in both cell types. Compounds without imidazole moiety did not diminish viability. In the presence of LA LH but not in the presence of carnosine a significant rise of intracellular amounts of histidine was detected in all cells. Formation of histamine was not detectable in the presence of carnosine, LA LH or histidine. In conclusion, the imidazole moiety of carnosine contributes to its anti-neoplastic effect, which is also seen in the presence of histidine and LA LH. Despite histamine had a strong effect on cell viability, formation of histamine is not responsible for the effects on cell viability of carnosine, LA LH and histidine.
ARTICLE | doi:10.20944/preprints202109.0424.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: high frequency dielectrophoresis; glioblastoma cells; single cell manipulation; microfluidic point-of-care device; cancer stem cells
Online: 24 September 2021 (11:11:35 CEST)
Glioblastoma (GBM) is one of the most aggressive solid tumors, particularly due to the presence of cancer stem cells (CSCs). Today the characterization of this type of cells with an efficient, fast and low-cost method remains an issue. Hence, we have developed a microfluidic lab-on-a-chip based on dielectrophoresis (DEP) single cell electro-manipulation to measure the two crossover frequencies: fx01 in low frequency range (below 500 kHz) and fx02 in Ultra High Frequency range (UHF, above 50 MHz). First, in vitro conditions were investigated. U87-MG cell lines were cultured in different conditions in order to induce an undifferentiated phenotype. Then, ex vivo GBM cells from patients’ primary cell culture, were passed through the developed microfluidic system and characterized in order to reflect clinical conditions. This article demonstrates that the usual exploitation of low frequency range DEP does not allow the discrimination of the undifferentiated from the differentiated phenotypes of GBM cells. However, the presented study highlights the use of UHF-DEP as a relevant discriminant parameter. The proposed microfluidic lab-on-a-chip is able to follow the kinetic of U87-MG phenotype transformation in a CSC enrichment medium and their cancer stem cells phenotype acquirement.
CASE REPORT | doi:10.20944/preprints201912.0264.v2
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: glioblastoma; brain tumor; paleolithic diet; ketogenic diet; paleolithic ketogenic diet; metabolic therapy; intestinal permeability; cancer treatment
Online: 9 November 2020 (11:25:35 CET)
Studies in animal models have suggested that the ketogenic diet may be effective in the treatment of cancer. However, human cohort studies on the ketogenic diet have, thus far, failed to show benefits in cancer survival or in any other hard clinical endpoints of the disease. This paper presents a case report of a patient with glioblastoma multiforme. The patient had initially been treated with standard oncotherapy including surgery, radiotherapy and chemotherapy. Despite standard treatment, the patient experienced a recurrence of the glioblastoma seven months later. Subsequently, the patient refused radiotherapy and chemotherapy and opted to use the paleolithic ketogenic diet (PKD) as a stand-alone therapy. Following the adoption of the PKD, progression of the disease has been completely halted. At the time of writing, the patient has remained in remission for 48 months, is without side-effects and experiences an excellent quality of life without the use of any drugs.
ARTICLE | doi:10.20944/preprints202002.0364.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma Multiforme; rat model; NK-Cell Therapy; MRI Cell traking; Fouresecent cell tracking; blood brain barrier
Online: 25 February 2020 (06:51:39 CET)
Natural killer (NK) cell therapy is one of the most promising treatments for Glioblastoma Multiforme (GBM). However, this emerging technology is limited by the availability of sufficient numbers of fully functional cells. Here, we investigated the efficacy of NK cells that were expanded and treated by interleukin-2 (IL-2) and heat shock protein70 (HSP70), both in vitro and in vivo. Proliferation and cytotoxicity assays were used to assess the functionality of NK cells in vitro, after which treated and naïve NK cells were administrated intra-cranially and systemically to compare the potential antitumor activities in our in vivo rat GBM models. In vitro assays provided strong evidence of NK cell efficacy against C6 tumor cells. In vivo tracking of NK cells showed efficient homing around and within the tumor site. Furthermore, significant amelioration of the tumor in rats treated with HSP70/Il-2 treated NK cells as compared to those subjected to non-treated NK cells, as confirmed by MRI, proved the efficacy of adoptive NK cell therapy. Moreover, results obtained with systemic injection confirmed migration of activated NK cells over the blood brain barrier and subsequent targeting of GBM tumor cells. Our data suggest that administration of HSP70/Il-2 treated NK cells may be a promising therapeutic approach to be considered in the treatment of GBM.
REVIEW | doi:10.20944/preprints201910.0296.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: nasal delivery; glioblastoma multiforme; drug delivery; nanoparticles; nose-to-brain delivery; pre-clinical studies; clinical evaluation
Online: 27 October 2019 (09:36:27 CET)
Glioblastoma (GBM) is the most lethal form of brain tumor, characterized by rapid growth and surrounding tissue invasion. The current standard treatment is surgery followed by radiotherapy, and concurrent chemotherapy, typically with temozolomide. Although extensive research has been performed over the past years to develop an effective therapeutic strategy for the treatment of GBM, efforts have not provided major improvements in the overall survival of patients with GBM. Thus, new therapeutic approaches are urgently needed. A major challenge in the development of therapies for central nervous system (CNS) disorders is overcoming the blood–brain barrier (BBB). In this context, the intranasal (IN) route of drug administration has been proposed as a non-invasive alternative route to directly targeting the CNS. In fact, this route of drug administration may bypass the blood-brain barrier and reduce systemic side effects. Recently, formulations have been developed to further enhance nose-to-brain transport, mainly with the use of nano-sized and nanostructured drug delivery systems. The focus of this review will be on the strategies developed to deliver a number of anticancer compounds for the treatment of GBM using the nasal administration. In particular, the specific properties of nanomedicines proposed for the nose-to-brain delivery will be critically evaluated. The number of preclinical and clinical data reviewed support the idea that nasal delivery of anticancer drugs might represent a breakthrough advancement in the fight against GBM.
ARTICLE | doi:10.20944/preprints201905.0374.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Keywords: Tumor microenvironment (TME), glioblastoma multiforme (GBM), GBM- associated macrophages (GAMs), exosomes, oncomiR-21, STAT3 inhibitor.
Online: 31 May 2019 (08:18:33 CEST)
Background: Tumor microenvironment (TME) plays a crucial role in virtually every aspect of tumorigenesis of glioblastoma multiforme (GBM). The dysfunctional TME promotes drug resistance, disease recurrence and distant metastasis. Recent evidence indicates that exosomes released by stromal cells within TME may promote oncogenic phenotypes via transferring signaling molecules such as cytokines, proteins and microRNAs. Results: In this study, clinical GBM samples were collected and analyzed. We found that GBM-associated macrophages (GAMs) secreted exosomes which were enriched with oncomiR-21. Co-culture of GAMs (and GAM derived exosomes) and GBM cell lines resulted in the increased GBM cells’ resistance against temozolomide (TMZ) by upregulating pro-survival gene, PDCD4 and stemness markers Sox2, STAT3, Nestin and miR-21-5p and increased M2 cytokines, IL-6 and TGF-β1 secreted by GBM cells, promoting the M2 polarization of GAMs. Subsequently, pacritinib treatment suppressed GBM tumorigenesis and stemness; more importantly, pacritinib-treated GBM cells showed markedly reduced ability to secret M2 cytokines and reduced miR-21 enriched exosomes secreted by GAMs. Pacritinib-mediated effects were accompanied by a reduction of oncomiR miR-21-5p, by which tumor suppressor PDCD4 was targeted. We subsequently established a patient-derived xenograft models where mice bore patient GBM and GAMs. The treatment of pacritinib, and the combination of pacritinib/TMZ appeared to significantly reduce tumorigenesis of GBM/GAM PDX mice, overcome TMZ-resistance, and M2 polarization of GAMs. Conclusion: In summation, we showed that potential of pacritinib alone or in combination with TMZ for suppressing GBM tumorigenesis via modulating STAT3/miR-21/PDCD4 signaling. Further investigations are warranted for adopting pacritinib for the treatment of TMZ-resistant GBM in the clinical settings.
ARTICLE | doi:10.20944/preprints202310.1264.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma; Fibronectin; Biomarkers; Cell signaling; In vitro techniques; Survivin; STAT3 transcription factor; PTEN protein; Prognosis; Computational biology
Online: 19 October 2023 (10:33:20 CEST)
Glioblastoma (GBM) is a representative malignant brain tumor characterized by a dismal prognosis, with survival rates of less than 2 years and high recurrence rates. Despite surgical resection and several alternative treatments, GBM remains a refractory disease due to its aggressive invasiveness and resistance to anticancer therapy. In this report, we explore the role of fibronectin type III domain containing 3B (FNDC3B) and its potential as a prognostic and therapeutic biomarker in GBM. GBM exhibited a significantly higher cancer-to-normal ratio compared to other organs, and patients with high FNDC3B expression had a poor prognosis (p < 0.01). In vitro studies revealed that silencing FNDC3B significantly reduced the expression of Survivin, an apoptosis inhibitor, and also reduced cell migration, invasion, extracellular matrix adhesion ability, and stem cell properties in GBM cells. Furthermore, we identified that FNDC3B regulates PTEN/PI3K/Akt signaling in GBM cells using MetaCore integrated pathway bioinformatics analysis and a proteome profiler phospho-kinase array with sequential western blot analysis. Collectively, our findings suggest FNDC3B as a potential biomarker for predicting GBM patient survival and for the development of treatment strategies for GBM.
ARTICLE | doi:10.20944/preprints202309.1490.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioblastoma; astrocytoma; lipid accumulation; mitochondrial dysfunction; tumor microenvironment; oxidative phosphorylation; glycolysis; immune evasion; therapeutic strategies; ultrastructural analysis
Online: 21 September 2023 (13:04:57 CEST)
Disrupted lipid metabolism is a characteristic of gliomas. This study utilizes an ultrastructural approach to characterize the prevalence and distribution of lipids within gliomas. This study made use of tissue from IDH1 wild type (IDH1-wt) glioblastoma (n=18) and IDH1 mutant (IDH1-mt) astrocytoma (n=12) tumors. We uncover a prevalent and intriguing surplus of lipids. The bulk of the lipids manifested as sizable cytoplasmic inclusions and extracellular deposits in the tumor microenvironment (TME); in some tumors the lipids were stored in the classical mem-braneless spheroidal lipid droplets (LDs). Frequently, lipids accumulated inside mitochondria, suggesting possible dysfunction of the beta-oxidation pathway. Additionally, the tumor vascula-ture are shown to have lipid deposits in their lumen and vessel walls; this lipid could have shifted in from the tumor microenvironment or have been produced by the vessel-invading tumor cells. Overproduction of lipids by the tumor is suspected to be due to a combination of two processes: i) dysfunctional oxidative phosphorylation in mitochondria that causes metabolic backup and ac-cumulation of acetyl-CoA, as well as ii) the overproduction of pyruvate due to the tumor cell reli-ance on overactive glycolysis. Tumor cells use lipids for structural components but cannot use them for energy if their oxidative phosphorylation is dysfunctional, which seems to be the case in the tumor cells we examined. This lipid-rich environment, however, offers tumor cells certain advantages: protection from the immune system, non-lipophilic drugs, and oxidative stress. Our research highlights the significant presence of lipid overproduction in both IDH1-wild type glio-blastoma and IDH1-mutant astrocytoma tumors, leading to diverse lipid accumulations in var-ious cellular compartments and structures. This lipid excess stems from disrupted beta-oxidation and dysfunctional oxidative phosphorylation pathways. The implications of this lipid-driven environment include structural support for the tumor cells and protection against immune re-sponses, non-lipophilic drugs, and free radicals.
ARTICLE | doi:10.20944/preprints202105.0524.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Hsp70; sandwich ELISA; liquid biopsy; tumor biomarker; exosomes; prediction; response monitoring; non-small cell lung carcinoma (NSCLC); glioblastoma
Online: 21 May 2021 (15:06:37 CEST)
In contrast to normal cells, tumor cells of multiple entities overexpress the Heat Shock Protein 70 (Hsp70) not only in the cytosol, but also present it on their plasma membrane in a tumor-specific manner. Furthermore, membrane-Hsp70 positive tumor cells actively release Hsp70 into lipid microvesicles termed exosomes into the blood. Due to conformational changes of Hsp70 in the lipid environment, most commercially available antibodies fail to detect membrane-bound and exosomal Hsp70. To fill this gap and to assess the role of exosomal Hsp70 in the circulation as a potential tumor biomarker, we established the novel complete Hsp70 (compHsp70) sandwich ELISA using two monoclonal antibodies (mAbs) that are able to recognize both, free and lipid-associated Hsp70 on the cell surface of viable tumor cells and exosomes. The epitopes of the mAbs cmHsp70.1 (aa 451-461) and cmHsp70.2 (aa 614-623) that are conserved among different species reside in the substrate-binding domain of Hsp70, with measured affinities of 0.42 nM and 0.44 nM, respectively. Validation of the compHsp70 ELISA revealed a high intra- and inter-assay precision, linearity in a concentration range of 1.56 to 25 ng/ml, high recovery rates of ‘spiked’ liposomal Hsp70 (>84%), comparable values between human serum and plasma samples, and no interference by food intake or age of the donors. Hsp70 concentrations in the circulation of patients with glioblastoma, squamous cell or adeno non-small cell lung carcinoma (NSCLC) at diagnosis were significantly higher than those of healthy volunteers. Hsp70 concentrations dropped concomitantly with the decrease in viable tumor mass on irradiation of patients with approximately 20 Gy (range 18 – 22.5 Gy) or after completion of radiotherapy (60 - 70 Gy). In summary, the compHsp70 ELISA presented herein provides a highly sensitive and reliable tool for measuring free and exosomal Hsp70 in liquid biopsies of tumor patients, levels of which can be used as a predictive tumor-specific biomarker, risk assessment and for monitoring therapeutic outcome.
ARTICLE | doi:10.20944/preprints202309.1880.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: FLAIR infiltration; brain tumors; extent of surgical resection; glioblastoma; overall survival; progression-free survival; pseudocapsule; neuro-oncology; tumor volume
Online: 28 September 2023 (03:26:09 CEST)
Background: Glioblastoma is the most common primary brain neoplasm in adults, with still a poor prognosis despite a constant effort to improve patients’ survival. Some neuroradiological volumetric parameters seem to play a predictive role on Overall Survival (OS) and Progression Free Survival (PFS). The aim of this study is to analyze the impact that the volumetric areas of contrast-enhancing tumor and perineoplastic edema have on survival of patients treated for glioblastoma; Methods: A series of 87 patients who underwent surgery was retrospectively analyzed; OS and PFS were considered as the end points of the study. For each patient a multidisciplinary revision was conducted in collaboration with the Neuroradiology and Neuro-Oncology board. A manual and semi-automatic measurement were adopted to perform the radiological evaluation: contrast Enhancement Preoperative (CE-PTV) and Postoperative Tumor Volume (CE-RTV), Edema/Infiltration Preoperative (T2/FLAIR-PV) and Postoperative Volume (T2/FLAIR-RV); necrosis volume inside the tumor (NV); total tumor volume, including necrosis (TV); Results: The median OS value was 9 months and the median PFS value was 4 m; the mean values were respectively 12,3 m and 6,9 m. Multivariate analysis showed that the OS related factors were: adjuvant chemo-radiotherapy (p < 0,0001), CE-PTV < 15 cm³ (p=0,03), surgical resection > 95% (p=0,004) and the presence of a “pseudo-capsulated” radiological morphology (p=0,04); Conclusions: maximal safe resection is one of the most relevant predictive factors for patients’ survival. The semi-automatic pre-operative MRI evaluation could play a key role in prognostically categorizing these tumors.
REVIEW | doi:10.20944/preprints202010.0623.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Glioblastoma; Neural Stem Cells; Mesenchymal Stem Cells; Stem Cell Therapy; Enzyme/Prodrug Therapy; Oncolytic Virotherapy; Nanoparticles; TRAIL; Cytokine Therapy
Online: 29 October 2020 (15:51:04 CET)
The potential of Neural Stem Cells (NSCs) to provide therapeutic benefit for a variety of neurological disorders, including brain malignancies, has been long recognized and has inspired many scientists to design, test and successfully demonstrate that NSCs are efficient and effective therapeutic agents. Glioblastoma, the deadliest form of primary brain tumor, despite extensive and sustained efforts to find better therapies, remains a disease without cure, with a median survival after diagnosis of less than two years. Treatment resistance in glioblastoma is in large part attributed to limitations in the delivery and distribution of therapeutic agents administered either systemically or directly into the tumor due to the highly invasive nature of this cancer and its abnormal intratumoral vasculature. Stem Cells (SCs) have an innate tumor-tropic migratory behavior, can be modified to deliver a variety of therapeutic agents and efficiently distribute their cargo into brain tumors, pursuing invading streams of tumor cells, deep into the brain parenchyma. Over the last twenty years, numerous preclinical trials have demonstrated the feasibility and efficacy of SCs as antiglioma agents, leading to the development of trials to test these therapies in the clinic. In this review we present and analyze these studies and discuss mechanisms underlying their beneficial effect, highlighting experimental progress, limitations and the emergence of promising new therapeutic avenues. We hope to increase awareness of the advantages of using SCs for the treatment of glioblastoma and inspire further studies that will lead to accelerated implementation of effective therapies.
ARTICLE | doi:10.20944/preprints202107.0503.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Cytotoxicity; Glioblastoma multiform; Lactate dehydrogenase (LDH); Poly D- L-lactic-co-glycolic acid (PLGA); U-87 MG glioma cell lines
Online: 21 July 2021 (16:37:21 CEST)
PHLNs (polymeric lipid hybrid nanoparticles) are core–shell nanoparticle structures made up of polymer cores and lipid shells that have properties similar to both polymeric nanoparticles and liposomes. Methotrexate (MTX) loaded PLHNPs containing tween 80, phosphatidylcholine, poly D, L-lactic-co-glycolic acid (PLGA) & glyceryl tripalmitate prepared using solvent injection & homogenization method for glioblastoma treatment option. The MTX loaded PLHNPs optimized by Box–Behnken design to minimize particle size, higher entrapment efficacy, and maximize MTX concentration in the brain at 4h. The particle size, entrapment efficacy, concentration of drug in brain at 4h, zeta potential and AUC(Brain)/AUC(Plasma) ratio were in the range of 173.51-233.37nm, 70.56-86.34%, 6.38-12.38 μg/mL, 25.78-36.31mV & 1.02-5.32. in-vitro drug release studies, cellular internalization of optimized formulation against U-87 MG shows good anticancer effects.
REVIEW | doi:10.20944/preprints201908.0274.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: electricity; tumor treating fields; extremely low frequency; pulsed electric fields; new cancer treatment modalities; glioblastoma; electroporation; electrofusion; electrochemotherapy; gene electrotransference
Online: 26 August 2019 (16:04:26 CEST)
This paper is a mini literature review about electromagnetic field’s effects on cells, tissues and new treatment modalities. We have reviewed a papers which have been published in high quality journals in the last 5 years as two authors. This review’s aim is to be a resource for experimental studies about electricity’s effects on cell biology and pathophysiology. As a result of this literature review, we found that especially extremely low electric frequency and intermediate frequency fields have very important pathophysiological effects. We have mentioned four important expressions on this subject; electroporation, electrofusion, electrochemotherapy, gene electrotransference. Two different new treatment approaches have been developed by use of these two important electrical waves. First is tumor treating fields and the other is pulsed electric fields. Most studies in literature have been done with extremely low frequency and pulsed electric fields. In terms of diseases, most studies are about glioblastoma multiforme and malign melanoma.Most studies in literature have been done with extremely low frequency and pulsed electric fields. In terms of diseases, most studies are about glioblastoma and melanoma.