ARTICLE | doi:10.20944/preprints201912.0357.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: microfluidics; immunophenotyping; FISH; liquid biopsy; circulating leukemia cells; circulating plasma cells
Online: 27 December 2019 (02:30:15 CET)
The role of circulating plasma cells (CPCs) and circulating leukemic cells (CLCs) as biomarkers for several blood cancers, such as multiple myeloma and leukemia, respectively, have recently been reported. These markers can be attractive due to the minimally invasive nature of their acquisition through a blood draw (i.e., liquid biopsy) negating the need for painful bone marrow biopsies. CPCs or CLCs can be used for cellular/molecular analyses, such as immunophenotyping or fluorescence in situ hybridization (FISH). FISH, which is typically carried out on slides involving complex workflows, becomes problematic when operating on CLCs or CPCs due to their relatively modest numbers. Here, we present a microfluidic device for characterizing CPCs and CLCs enriched from peripheral blood using immunofluorescence or FISH. The microfluidic possessed an array of cross-channels (2-4 µm in depth and width) that interconnected a series of input and output fluidic channels. Placing a cover plate over the device formed microtraps, the size of which was defined by the width and depth of the cross-channels. This microfluidic chip allowed for automating immunofluorescence and FISH requiring the use of small volumes of reagents, such as antibodies and probes, as compared to slide-based immunophenotyping and FISH. In addition, the device could secure FISH results in <4 h compared to 2-3 d for conventional FISH.
ARTICLE | doi:10.20944/preprints202005.0312.v1
Subject: Life Sciences, Biochemistry Keywords: marine invertebrates; glycosaminoglycans; platelets; circulating tumor cells; circulating tumor microemboli; hematogenic metastasis
Online: 19 May 2020 (07:45:44 CEST)
Although metastasis is the primary cause of death on patients with malignant solid tumors, efficient antimetastatic therapies are not clinically available thus far. Sulfated glycosaminoglycans from marine sources have shown promising pharmacological effects, acting in different steps of the metastatic process. Oversulfated dermatan sulfate from ascidians is effective in preventing metastasis by inhibition of P-selectin, a platelet surface protein involved in the platelet-tumor cell emboli formation. We report in this work that the heparan sulfate isolated from the viscera of the ascidian Phallusia nigra drastically attenuates metastasis of colon carcinoma cells in mice. Our in vitro and in vivo assessments demonstrate that the P. nigra glycan has very low anticoagulant and antithrombotic activities and a reduced hypotension potential, although efficiently preventing metastasis. Therefore, it may be a promising candidate for the development of a novel anti-metastatic drug.
CASE REPORT | doi:10.20944/preprints202008.0688.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: lung disease; pulmonary embolis; circulating anticoagulant
Online: 31 August 2020 (03:26:55 CEST)
The quarantine imposed as the response to the COVID 19 pandemic has been related to an increase in cases of thromboembolism in Non-COVID19 patients .We report the case of a patient with pulmonary thromboembolism without usual triggering causes during the quarantine period, related to a previously undiagnosed hypercoagulable condition.
ARTICLE | doi:10.20944/preprints202101.0129.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Non-small cell lung cancer; Circulating tumor cells; Circulating tumor-derived endothelial cells; Biomarkers; SE-iFISH
Online: 6 January 2021 (15:32:40 CET)
Effective biomarkers are essential to the early diagnosis of non-small cell lung cancer (NSCLC). Herein, a retrospective study of 49 newly diagnosed and recurrent NSCLC patients, 31 patients with benign pulmonary disease and 24 healthy volunteers was conducted, to evaluate the diagnostic value of circulating rare cells for NSCLC. The expression of circulating tumor cells (CTCs) and circulating tumor-derived endothelial cells (CTECs) in peripheral blood were measured by subtraction enrichment-immunostaining-fluorescence in situ hybridization (SE-iFISH). The level of CTCs (P＜0.001) and CTECs (P＜0.001) was significantly higher in NSCLC group than that in benign pulmonary disease group. The proportion of small CTCs (P＜0.001) and CTECs (P＜0.0001) significantly increased from benign lung disease individuals to NSCLC patients. The AUC of ROC curves of total CTCs and CTECs were 0.815 (95%CI: 0.722~0.907), 0.739 (95%CI: 0.618~0.860), respectively. The cut-off values for discriminating NSCLC with benign lung disease patients were total CTCs 11.5 units/6ml and total CTECs 10.5 units/6ml, with sensitivity and specificity being 67.3% and 83.9%, 77.6% and 77.4%, respectively. When CTCs and CTECs were combined, predictive value significantly increased to 82.6% as measured by the area under the curve. Small CTCs and triploid CTCs had high positive predictive value (PPV) and positive likelihood ratio (LR+) of the diagnosis of NSCLC in early stage. CTCs and CTECs can not only be used as new biomarkers for the diagnosis of NSCLC, but can also improve diagnostic performance of the early stage NSCLC. Moreover, the combined examination of CTCs and CTECs is be superior to the single.
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: whole exome sequencing; melanoma; circulating tumor dna
Online: 4 October 2019 (10:35:02 CEST)
The use of circulating cell-free (cf) DNA to monitor cancer progression and response to therapy has significant potential but there is only limited data on whether this technique can detect the presence of low frequency subclones that may ultimately confer therapy resistance. In this study, we sought to evaluate whether whole-exome sequencing of cfDNA can accurately profile the mutation landscape of metastatic melanoma. We used whole-exome sequencing (WES) to identify variants in matched tumor-derived genomic (g) DNA and plasma-derived cfDNA isolated from a cohort of 10 metastatic cutaneous melanoma patients. WES parameters such as sequencing coverage and total sequencing reads were comparable between gDNA and cfDNA. There was significant concordance between gDNA and cfDNA based on the total number of variants identified and the degree of overlap in variants which was independent of the site of tumor biopsy. The mutant allele frequency of common single nucleotide variants was lower in cfDNA reflecting lower read depth and dilution of circulating tumor DNA in the circulation by other cfDNA species. In addition to known melanoma driver mutations, several other melanoma-associated mutations were found to be concordant between matched gDNA and cfDNA. This study highlights that WES of cfDNA can capture clinically-relevant mutations present in melanoma metastases, but does not appear to provide any additional unique information on tumor heterogeneity. Targeted deep sequencing may be required to detect low frequency genomic aberrations known for predicting therapy resistance.
REVIEW | doi:10.20944/preprints202112.0063.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: circulating tumor cells; dielectrophoresis; prostate cancer; detection; prognosis
Online: 6 December 2021 (12:03:13 CET)
Liquid biopsy via isolation of circulating tumour cells (CTCs) represents a promising diagnostic tool capable of supplementing state-of-the-art for prostate cancer (PC) prognosis. Unfortunately, most of CTC technologies, such as AdnaTest or Cellsearch, critically rely on the Epithelial-Cell-Adhesion-Molecule (EpCAM) marker, limiting the possibility of detecting stem-like cells (CSCs) and mesenchymal-like cells (EMT-CTCs) that are present during PC progression. In this tontext, dielectrophoresis (DEP) is an epCAM independent, label-free, enrichment system, separating rare cells simply on the basis of their specific electrical properties. As compared to other technollgies, DEP represents a superior technique in terms of running costs, cells yield and specificity, but due to its higher complexity, requires still further technical as well as clinical development. Interestingly, DEP can be improved by the use of microfluid, nanostructured materials and fluoroimaging in order to increase its potential applications. In the context of PC, the utility of DEP can be translated in its capacity to detect CTC in the bloodstream in their epithelial, mesenchymal, or epithelial-mesenchymal phenotypes, which should be taken into account when choosing CTC enrichment and analysis methods for PC prognosis and early diagnosis.
REVIEW | doi:10.20944/preprints202004.0238.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Covid; NET; neutrophils; circulating DNA; therapy; innate immune response
Online: 15 April 2020 (09:55:34 CEST)
Neutrophils play an important role as the first line of innate immune defense. One function of neutrophils, called neutrophil extracellular traps (NETs), has been discovered recently. NETs are extensive fibrous structures released extracellularly from activated neutrophils in response to infection. They are composed of cytosolic protein assembled on a scaffold of released chromatin. These structures suppress the dissemination of micro-organisms in blood by trapping them mechanically, and by exploiting coagulant function to segregate them within the circulation. In addition, NET components (DNA, histone, and granule proteins) also contribute to the triggering of an inflammatory process. NET function, however, can be regarded as a double-edged sword. On one hand, NET formation is an efficient strategy for neutralizing invading micro-organisms. On the other hand, NET can be harmful to the host, as its exposed by-products that are toxic to endothelial cells and parenchymal tissue. We present here the analogous biological and physiological features of the harmful positive amplification loop between inflammation and tissue damage induced by NETosis dysregulation and Coronavirus Disease-2019 (COVID-19) pathogenesis. Considering the rapid evolution of this disease symptoms and its lethality, we hypothesize that COVID-19 progresses under an amplifier loop, leading to an massive, uncontrolled inflammation process. We also describe the correlations of COVID-19 symptoms and biological features with those consecutive to uncontrolled NET formation causing various sterile or infectious diseases. General clinical conditions, and numerous pathological and biological features, are analogous with NETs deleterious effects. We postulate that Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV2) induces a disproportionate virus-induced NET release, and that this plays a key role in COVID-19 pathogenesis. While neutrophils are the principal starting point for extracellular and circulating DNA release, targeting NETs rather than neutrophils themselves may stand for an effective strategy. This paper offers an in-depth review of NET formation, function and pathogenic dysregulation, as well as of current and future therapies to control NET unbalance. As such, it enables us also to suggest new therapeutic strategies to fight COVID-19. In combination with or independent of the latest tested approaches, we propose that, in the short term, deoxyribonuclease I (DNase-1) treatment should be evaluated; we also advocate a significant increase in research on the development of toll-like receptors (TLR) and C-type Lectin like receptors (CLEC) inhibitors, and on anti-IL26 therapies.
ARTICLE | doi:10.20944/preprints201810.0709.v1
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: ALS; ALS rehabilitation; myomiRs; circulating miRNAs; muscle; motor neuron
Online: 30 October 2018 (07:15:24 CET)
Amyotrophic lateral sclerosis (ALS) is a rare, progressive, neurodegenerative disorder caused by degeneration of upper and lower motor neurons. The disease process leads from lower motor neuron involvement to progressive muscle atrophy, weakness, fasciculations for the upper motor neuron involvement to spasticity. Muscle atrophy in ALS is caused by a dysregulation in the molecular network controlling fast and slow muscle fibres. Denervation and reinnervation processes in skeletal muscle occur in the course of ALS and are modulated by rehabilitation. MicroRNAs (miRNAs) are small non-coding RNAs that modulate a wide range of biological functions under various pathophysiological conditions. MiRNAs can be secreted by various cell types and they are markedly stable in body fluids. MiR-1, miR-133 a, miR-133b, and miR-206 are called “myomiRs” and are considered markers of myogenesis during muscle regeneration and neuromuscular junction stabilization or sprouting. We observed a positive effect of a standard aerobic exercise rehabilitative protocol conducted for six weeks in 18 ALS patients during hospitalization in our center. We correlated clinical scales with molecular data on myomiRs. After six weeks of moderate aerobic exercise, myomiRNAs were down-regulated, suggesting an active proliferation of satellite cells in muscle and increased neuromuscular junctions. Our data suggest that circulating miRNAs modulate during skeletal muscle recovery in response to physical rehabilitation in ALS.
ARTICLE | doi:10.20944/preprints201810.0154.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: Nectin-4; metastasis; angiogenesis; circulating tumor cells; cancer relapse
Online: 8 October 2018 (15:52:03 CEST)
In the present study, we have systematically examined the clinical significance of Nectin-4 (encoded by the PVRL-4 gene), a marker for breast cancer stem cells (CSCs), in cancer metastasis and angiogenesis using a variety of human specimens, including invasive duct carcinoma (IDC) with multiple grades, several types of primary tumors to local and distant relapses, lymph node metastases and circulating tumor cells (CTCs). Nectin-4 was overexpressed in more than 92% of samples with 65.2% Nectin-4 positive cells. The level of expression was increased with increasing tumor grade (GI-III) and size (T1-4) of IDC specimens. More induction of Nectin-4 was noted in relapsed samples from a variety of tumors (colon, tongue, liver, kidney, ovary, buccal mucosa) in comparison to primary tumors, while paired adjacent normal tissues do not express any Nectin-4. A high expression of Nectin-4 along with other representative markers in CTCs and lymph node metastasis was also observed in cancer specimens. An increased level of Nectin-4 along with representative metastatic (CD-44, Sca1, ALDH1, Nanog) and angiogenic (Ang-I, Ang-II, VEGF) markers was noted in metastatic tumors (local and distant) in comparison to primary tumors that were correlated with different grades of tumor progression. In addition, greater expression of Nectin-4 was observed in secondary tumors (distant metastasis, e.g., breast to liver or stomach to gallbladder) in comparison to primary tumors. Nectin-4 was overexpressed at all stages of metastasis and angiogenesis, thus appearing to play a major role in tumor relapse through the PI3K-Akt-NFκβ pathway.
REVIEW | doi:10.20944/preprints202108.0518.v2
Subject: Medicine & Pharmacology, General Medical Research Keywords: liquid biopsy; circulating biomarkers; Alzheimer’s disease; neurodegeneration; cell-free; diagnosis
Online: 8 March 2022 (09:56:01 CET)
Alzheimer’s disease is the most common neurodegenerative disease and affects persons of all races, ethnic groups, and sexes. The disease is characterized by neuronal loss leading to cognitive decline and memory loss. There is no cure and the effectiveness of existing treatments is limited and depends on the time of diagnosis. The long prodromal period, during which patients’ ability to live a normal life is not affected despite neuronal loss, often leads to a delayed diagnosis because it can be mistaken for normal aging of the brain. In order to make a substantial impact on AD patients, early diagnosis may provide a greater therapeutic window for future therapies to slow AD-associated neurodegeneration. Current gold standards for disease detection include magnetic resonance imaging and positron emission tomography scans, which visualize amyloid β and phosphorylated tau depositions and aggregates. Liquid biopsies, already an active field of research in precision oncology, are hypothesized to provide early disease detection through minimally or non-invasive sample collection techniques. Liquid biopsies in Alzheimer’s disease have been studied in cerebrospinal fluid, blood, ocular, oral, and olfactory fluids. However, most of the focus has been on blood and cerebrospinal fluid due to biomarker specificity and sensitivity attributed to the effects of the blood-brain barrier and inter-laboratory variation during sample collection. Many studies have identified amyloid β and phosphorylated tau levels as putative biomarkers, however, advances in next-generation sequencing-based liquid biopsy methods have led to significant interest in identifying nucleic acids species associated with Alzheimer’s disease from liquid tissues. Differences in cell-free RNAs and DNAs have been described as potential biomarkers for AD and hold the potential to affect disease diagnosis, treatment, and future research avenues.
ARTICLE | doi:10.20944/preprints202106.0506.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Cell main spectra; Circulating tumour cell; MALDI-TOF; Method development
Online: 21 June 2021 (11:31:02 CEST)
Circulating atypical cells (CAC) are released from a primary tumour site into peripheral blood and are indicators of cancer metastasis. CAC occur at very low frequency in circulating blood, and their detection remains challenging. Moreover, white blood cells (WBC) are the major contaminant in enriched CAC samples. Here, we developed matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) as a novel CAC characterization platform. Main spectra profiles (MSP) of normal and cancer cells were generated by MALDI-TOF MS, and a cell-main spectra database was then compiled and analysed using the MALDI Biotyper software. Logarithmic scores accurately predicted distinct cell types. The feasibility of this workflow was then validated using simulated samples, which were prepared by 5,000 WBC of three healthy individuals spiked with varying numbers (3, 6, 12, 25, 50 and 100) of lung, colon, or prostate cancer cells. MALDI-TOF MS was able to detect cancer cells down to six cells over the background noise of 5,000 WBC with significantly higher predictive scores as compared to WBC alone. Further development of cell-MSP database to cover all cancer types sourced from cell lines and patient tumours may enable the use of MALDI-TOF MS as a cancer-screening platform in clinical settings in the future.
Subject: Medicine & Pharmacology, General Medical Research Keywords: circulating tumor biomarkers; extracellular vesicles; biological nanoparticles; liquid biopsy; biosensing
Online: 31 January 2020 (05:18:15 CET)
Exosomes are nano-sized extracellular vesicles excreted by mammalian cells that circulate freely in the bloodstream of living organisms. Exosomes have a lipid bilayer that encloses genetic material used in intracellular communication (e.g., double-stranded DNA, micro-RNAs, and messenger RNA). Recent evidence suggests that dysregulation of this genetic content within exosomes has a major role in tumor progression and in the surrounding microenvironment. Motivated by this discovery, we focused here on using exosomal biomarkers as a diagnostic and prognostic tool for cancer. In this review, we discuss recently discovered exosome-derived proteomic and genetic biomarkers used in cancer diagnosis and prognosis. Although several genetic biomarkers have been validated for their diagnostic values, proteomic biomarkers are still being actively pursued. We discuss both commercial technologies and emerging technologies for exosome isolation and analysis.
Subject: Medicine & Pharmacology, Obstetrics & Gynaecology Keywords: circulating endometrial cells; endometriosis; rare cells; menstrual cycle; liquid biopsy
Online: 18 August 2019 (16:36:07 CEST)
The focus of the presented work was to isolate and characterize circulating endometrial cells (CECs) enriched from peripheral blood (PB) of patients with diagnosed endometriosis to support endometriosis diagnosis and treatment. Material and Methods Blood samples (n=423) were tested for CECs presence. Subsequently, gene expression analysis (GEA) was carried out for CECs. In parallel, the presence and character of CECs was tested during phases of menstrual cycle (MC) (n= 11). CECs were isolated by size-based separation from 2x 8ml PB. Results CECs were detected in 78.4% of blood samples. In line with the revised American Fertility Society (rAFS) classification CECs presence was confirmed in all the acknowledged endometriosis stages: minimal, mild, moderate and severe. Surprisingly, the highest CEC negativity rate was reported for severe disease (21.1%). The highest CEC numbers were detected in the mid-secretory periods of MC, which corresponds with uterine lining decidualization. The cytomorphology of CECs captured during MC is changing between the epithelial, stromal and stem cell-like. CECs captured in mid-secretory period expressed KRT18, NANOG and VIM in higher amounts when compared to the genes in the proliferative phase of MC when KRT19 and ESR1 were mostly observed. GEA of the super-positive CECs samples (1000 CECs/8mL PB) revealed high expression of KRT18, VIM, NANOG and FLT1. The expression of these genes was elevated in the endometriosis tissue samples and endometrioma, too. Conclusion The panel of the identified CECs - genes could be tested in a prospective manner to confirm the predictive value of CECs in endometriosis diagnostics.
ARTICLE | doi:10.20944/preprints202210.0046.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: cancer; circulating tumour cell clusters; metastasis; TGF-β1; extravasation; phenotypic plasticity
Online: 5 October 2022 (16:35:01 CEST)
Metastasis – the ability of cancer cells to disperse and colonize distant locations in the body, is responsible for the majority of cancer-related deaths. While in the vasculature, tumour cells are referred to as circulating tumour cells (CTCs) and can manifest either as single cells or clusters of cells, with the latter being the most aggressive. Despite their significant role in the metastatic process, the mechanisms through which CTC clusters extravasate and disseminate remain largely unknown. Notably, CTC clusters have been found to contain platelets, which are known to secrete many factors, including Transforming Growth Factor Beta 1 (TGF-β1) – a signaling molecule that has been widely implicated in many aspects of cancer, including the extravasation of single CTCs. To address whether the interaction between platelets and CTC clusters might also facilitate the extravasation of CTC clusters, we evaluated the effect of exogenous TGF-β1 on an experimentally evolved lung cancer cell line that grows as cell clusters that we previously developed and used to investigate the biology of CTC clusters. We found that exogenous TGFβ1 induces the dissociation of clusters and cell adherence. Furthermore, once adhered, cells release their own TGF-β1 and are able to migrate and invade in the absence of exogenous TGFβ1. Based on these findings we propose a model that involves both paracrine and autocrine TGFβ1-mediated phenotypic plasticity resulting in the acquisition of traits that enable the extravasation of CTC clusters as single cells.
REVIEW | doi:10.20944/preprints202205.0368.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: circulating tumor DNA; colon cancer; colorectal cancer; minimal residual disease; adjuvant chemotherapy
Online: 27 May 2022 (03:52:10 CEST)
Circulating tumor DNA (ctDNA), the tumor-derived cell-free DNA fragments in the bloodstream carrying tumor-specific genetic and epigenetic alterations, represents an emerging novel tool for minimal residual disease (MRD) assessment in patients with resected colorectal cancer (CRC). For many decades, precise risk-stratification following curative-intent colorectal surgery has remained an enduring challenge. The current risk stratification strategy relies on clinicopathologic characteristics of the tumors that lacks precision and results in over-and undertreatment in a significant proportion of patients. Consequently, a biomarker that can reliably identify patients harboring MRD would be of critical importance in refining patient selection for adjuvant therapy. Several prospective cohort studies have provided compelling data suggesting that ctDNA could be a robust biomarker for MRD that outperforms all existing clinicopathologic criteria. Numerous clinical trials are currently underway to validate the ctDNA-guided MRD assessment and adjuvant treatment strategies. Once validated, the ctDNA technology will likely transform the adjuvant therapy paradigm of colorectal cancer, supporting ctDNA-guided treatment escalation and de-escalation. The current article presents a comprehensive overview of the published studies supporting the utility of ctDNA for MRD assessment in patients with CRC. We also discuss ongoing ctDNA-guided adjuvant clinical trials that will likely shape future adjuvant therapy strategies for patients with CRC.
ARTICLE | doi:10.20944/preprints202109.0156.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: circulating thymidine kinase 1; cell loss; biomarker; early treatment response; breast cancer
Online: 8 September 2021 (16:25:39 CEST)
Complete pathologic response (pCR) predicts the long-term outcome of neoadjuvant treated (NAC) breast cancer (BC) but is reached in <10% of hormone-receptor-positive patients. Biomarkers able to guide adjustment or interruption of an ineffective therapy are desired. Here, we evaluated whether shifts in the serum concentration of thymidine kinase 1 (sTK1) during NAC could be utilized as a biomarker. In the PROMIX trial, women with localized HER2- BC received neoadjuvant epirubicin/docetaxel in six cycles. sTK1 was measured with an ELISA in 54 patients at cycles 1-4 and in a total of 131 patients before and 48h after cycle 1. The prognostic significance of the results was evaluated by log-rank tests of Kaplan–Meier estimates. Treatment resulted in a 2-fold increase of sTK1 before and 3-fold increase 48h after the cycles, except for the first cycle, where half of patients reacted with a decrease (post/pre sTK1- ratio <1.12) and the other half reacted with an increase (ratio >1.12). OS rates in ER+ patients with ratios of >1.12 and <1.12 were 97.7% and 78% (p=0.005), respectively, and DFS rates were 90.7% and 68% (p=0.006), respectively. Thus, response of sTK1 at the first cycle of chemotherapy could be used both as an early biomarker for guidance of chemotherapy and for the study of inherent tumor chemo-sensitivity, which could predict long-term outcome prior to therapy.
REVIEW | doi:10.20944/preprints202108.0513.v1
Subject: Keywords: liquid biopsy; epilepsy; circulating biomarkers; cfDNA; lncRNA; tRNA; miRNA; diagnosis; prognosis; therapeutics
Online: 26 August 2021 (16:40:54 CEST)
Epilepsy is one of the most common disorders of the central nervous system, impacting nearly 50 million people around the world. Heterogeneous in nature, epilepsy presents in children and adults alike. Currently, surgery is the only treatment that can cure epilepsy. However, not all individuals are eligible or have successful outcomes. Difficulty in accessing samples of human brain tissue along with advances in sequencing technology have driven researchers to investigate sampling liquid biopsies in blood, serum, plasma, and cerebrospinal fluid within the context of epilepsy. Liquid biopsies provide minimal or non-invasive sample collection approaches and can be assayed relatively easily across multiple time points, unlike tissue-based sampling. Various efforts have investigated circulating nucleic acids from these samples including microRNAs, cell-free DNA, transfer RNAs, and long non-coding RNAs. Here, we review nucleic acid-based liquid biopsies in epilepsy to improve understanding of etiology, diagnosis, prediction, and therapeutic monitoring.
ARTICLE | doi:10.20944/preprints202012.0556.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Pancreatic cancer; recurrence; metastasis; surgical resection; circulating tumour cells; CTC; CellSearch; prognostication
Online: 22 December 2020 (12:02:41 CET)
In patients with presumed pancreatic ductal adenocarcinoma (PDAC), biomarkers that may open for personalised, risk-adapted treatment are lacking. The study analysed the impact of circulating tumour cells (CTCs) on the patterns of recurrence and survival in 98 patients resected for PDAC with 5-10 years of follow-up. Preoperative samples were analysed by the CellSearch® system for EpCAM+/DAPI+/CK+/CD45- CTCs. CTCs were detected in 7 of the 98 patients. CTCs predicted a significantly shorter median DFS of 3.3 vs. 9.2 months and a median CSS of 6.3 vs. 18.5 months. Relapse status was confirmed by imaging for 87 patients. Of these, 58 developed distant metastases (DM) and 29 cases isolated local recurrence (ILR) as first event. All patients with CTCs experienced DM. pN-status and histological grade >2 were other independent risk factors for DM, but only CTCs predicted significantly shorter cancer-specific, disease-free and post-recurrence survival. We conclude that CTC presence in resected PDAC patients predicted early distant metastasis and impaired survival. The impact of CTCs was comparable to that of histopathological risk factors and exceeded the effect size of other preoperative parameters. Thus, preoperative CTCs alone or in combination with histopathological factors may guide initial treatment decisions in patients with resectable PDAC in the future.
ARTICLE | doi:10.20944/preprints202012.0406.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Hepatocellular carcinoma; transcatheter arterial chemoembolization; circulating tumor cells; tumor progression; predictive marker
Online: 16 December 2020 (11:26:42 CET)
Circulating tumor cells (CTCs) enumeration is a promising technique to predict cancer prognosis and treatment response. CTCs were evaluated in healthy subjects, cirrhotic controls and hepatocarcinoma (HCC) patients. CTCs were isolated using microfluidic system based on the expression of EpCAM, EGFR and three epithelial to mesenchymal transition (EMT) markers. Patients were stratified according to disease progression and exitus. Although counts of individual CTCs, clustered CTCs and α-fetoprotein (AFP) at basal level in patients with HCC were significantly increased compared with the values obtained in cirrhotic patients and control subjects, only individual CTCs (p=0.027), but not clustered CTCs (p=0.063) and AFP (p=0.072), were independent predictors of HCC development. The univariate regression model showed that basal levels of CTCs46 were related to high risk of HCC (Odds Ratio 3.467, p=0.011). The stratification of our cohort according to disease progression and death showed that basal individual CTCs 76 (Hazard Ratio 5.131, p=0.004) were related to disease progression, as well as the difference of clustered CTCs between 1-month and baseline levels 1.5 were related to death (Hazard Ratio 10.204, p=0.036). In conclusion, the preoperative and 1-month measurements of CTCs in blood constitute useful markers to predict the outcome of patients under TACE treatment.
REVIEW | doi:10.20944/preprints202010.0154.v1
Subject: Life Sciences, Biochemistry Keywords: DNA methylation; epigenetics; biomarkers; circulating DNA; cfDNA; prostate cancer; early detection; prognosis
Online: 7 October 2020 (09:27:34 CEST)
There is a major clinical need for accurate biomarkers for prostate cancer prognosis, to better inform treatment strategies and disease monitoring. Current clinically recognised prognostic factors, including prostate-specific antigen (PSA) levels, lack sensitivity and specificity in distinguishing aggressive from indolent disease, particularly in patients with localised intermediate grade prostate cancer. There has therefore been a major focus on identifying molecular biomarkers that can add prognostic value to existing markers, including investigation of DNA methylation, which has a known role in tumorigenesis. In this review, we will provide a comprehensive overview of the current state of DNA methylation biomarker studies in prostate cancer prognosis, and highlight the advances that have been made in this field. We cover the numerous studies into well-established candidate genes, and explore the technological transition that has enabled hypothesis-free genome-wide studies and the subsequent discovery of novel prognostic genes.
ARTICLE | doi:10.20944/preprints201905.0226.v1
Subject: Keywords: Circulating Tumor Cells; CTC; Liquid Biopsy; CTM; CTMat; CTC Biology; CTC Capture Technology
Online: 17 May 2019 (16:15:53 CEST)
Circulating tumor cells (CTC) and circulating tumor microemboli (CTM) have been shown to correlate negatively with patient survival. Actual CTC counts before and after treatment can be used to aid in prognosis of patient outcomes. The presence of circulating tumor materials (CTMat) can advertise the presence of metastasis before clinical presentation, enabling early detection of relapse. Importantly, emerging evidence is indicating that cancer treatments can actually increase the incidence of CTCs and metastasis in pre-clinical models. Subsequently, the study of CTCs, their biology and function are of vital importance. Emerging technologies for the capture of CTC/CTMs and CTMat are elucidating vitally important biological and functional information that can lead to important alterations in how therapies are administered. This paves the way for the development of a “liquid biopsy” where treatment decisions can be informed by information gleaned from tumor cells and tumor cell debris in the blood.
REVIEW | doi:10.20944/preprints201812.0066.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: renal cell carcinoma; circulating DNA; CTC; diagnosis; follow-up; genetic alteration; target therapy
Online: 5 December 2018 (08:01:30 CET)
Liquid biopsy, based on the circulating tumor cells (CTCs) and cell-free nucleic acids has potential applications at multiple points throughout the natural course of cancer, from diagnosis to follow-up. The advantages of doing ctDNA assessment vs. tissue-based genomic profile are the minimal procedural risk, the possibility to serial testing in order to monitor disease-relapse and response to therapy over time and to reduce hospitalization costs during the entire process. However some critical issues related to ctDNA assays should be taken in consideration. The sensitivity of ctDNA assays depends on the assessment technique and genetic platforms used, on tumor-organ, stage, tumor heterogeneity, tumor clonality. The specificity is usually very high, whereas the concordance with tumor-based biopsy is generally low. In patients with renal cell carcinoma (RCC) qualitative analyses of ctDNA have been performed with interesting results regarding selective pressure from therapy, therapeutic resistance, exceptional treatment response to everolimus and mutations associated with aggressive behavior. Quantitative analyses showed variations of cfDNA levels at different tumor stage. Compared to CTC assay, ctDNA is more stable than cells and easier to isolate. Splice variants, information at single-cell level and functional assays along with proteomics, transcriptomics and metabolomics studies can be performed only in CTCs.
ARTICLE | doi:10.20944/preprints201701.0125.v1
Subject: Engineering, Energy & Fuel Technology Keywords: wellbore pressure analysis; equivalent circulating density; geothermal well; wellbore temperature distribution; mathematical modeling
Online: 27 January 2017 (03:10:16 CET)
The accurate wellbore pressure control not only prevents from lost circulation/blowout and fracturing formation by managing density of drilling fluid, but also improves productivity by mitigating reservoir damage. The geothermal pressure calculated by constant parameters for geothermal well would bring big error easily, as the changes of physical, rheological and thermal properties of drilling fluids with temperature were neglected. This paper researches the wellbore pressure coupling by calculating the temperature distribution with existed model, fitting the rule of density of drilling fluid with temperature and establishing mathematical models to stimulate the wellbore pressures, which is expressed as the variation of Equivalent Circulating Density (ECD) under different conditions. With this method, temperature and ECDs in the wellbore of the first medium-deep geothermal well ZK212 Yangyi Geothermal Field in Tibet were determined, and the sensitivity analysis was simulated by assumed parameters, i.e. circulating time, flow rate, geothermal gradient, diameters of wellbore, rheological models and regimes, the results indicated the geothermal gradient and flow rate were the most influence parameters on the temperature and ECD distribution, and additives added in drilling fluid should be careful which would change the properties of drilling fluid and induce the temperature redistribution. To make sure the safe drilling, velocity of pipes tripping into the hole, depth and diameter of wellbore are considered to control the surge pressure.
ARTICLE | doi:10.20944/preprints202210.0421.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Postoperative atrial fibrillation; cardiac surgery; conventional extracorporeal circulation; circulating ferritin levels; POAF onset biomarker
Online: 27 October 2022 (05:53:09 CEST)
Background: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery in conventional extracorporeal circulation (CECC), with an incidence of 15-50%. The POAF pathophysiology is not known, and no blood biomarkers exist. However, an association between increased ferritin levels and increased AF risk, has been demonstrated. Based on such evidence, here, we evaluated the effectiveness of ferritin and other haemato-chemical parameters as a POAF onset biomarker in subjected to cardiac surgery. Materials and Methods: We enrolled 90 patients (mean age= 66.9±2.8 years; 40 men and 20 females) with diverse heart pathologies and subjected to cardiothoracic surgery. Their blood samples were collected and used to determine haemato-chemical parameters. The tree test approach was used to detect the best data-driven ferritin cuff-off value (=141 ng/ml) to predict POAF risk. Results: The data obtained demonstrated significant higher concentrations, absolute values, and percentages, of ferritin, RDW, PLTs, in POAF patients. However, the ferritin resulted to be the independent factor associated with the onset POAF risk. Thus, we detected the ferritin cut-off value, which, when ≥ 141 ng/ml identifies the subjects at the highest POAF risk. Conclusions: Ferritin values≥ 141 ng/ml might be used as predictive POAF biomarker.
ARTICLE | doi:10.20944/preprints201811.0421.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: circulating tumor cells; CTCs; breast cancer; metastasis; death receptor; TRAIL; apoptosis; in vitro model
Online: 19 November 2018 (06:44:04 CET)
Circulating tumor cells (CTCs) in the peripheral blood are the precursors to distant metastasis but the underlying mechanisms are poorly understood. This study aims at understanding the molecular features within CTCs in relation to their metastatic potential. Using in vitro CTC models, in which breast cancer cell lines are cultured in non-adherent conditions simulating the microenvironment in the blood stream, we found that suspension culture resulted in resistance to TNF-related apoptosis inducing ligand (TRAIL)-mediated cell death. Such a resistance was directly correlated with a reduction in surface and total levels of DR5 protein. In the non-adherent state, cells underwent rapid autophagic flux characterized by an accumulation of autophagosome organelles. Notably, DR5 was translocated to autophagosomes and underwent lysosomal degradation. Our data suggest that CTCs may evade TNF cytokine mediated immune surveillance through downregulation of DR expression. The data warrants further studies in cancer patients to find the status of DRs and other molecular features within primary CTCs in relation to disease progression or chemoresistance.
ARTICLE | doi:10.20944/preprints202210.0325.v2
Subject: Materials Science, Biomaterials Keywords: nanozymes; circulating tumor nucleci acid; liquid biopsy; magnetic enrichment; minimal residual disease; cell-free RNA
Online: 24 October 2022 (10:33:57 CEST)
Iron oxide nanozymes are a form of nanomaterial with both superparamagnetic and enzyme-mimicking properties. Given the multifunctional nature of iron oxide nanozymes, it is attractive for creating iron oxide hybrid nanozymes through biomolecular modifications to imbue with auxillary properties. Such iron oxide hybrid nanozymes can be useful for rapid and cost-effective analysis of circulating tumor nucleic acids (ctNAs) in patient liquid biopsies during minimal residual disease (MRD) monitoring of cancer recurrence. Herein, the use of streptavidin-modified iron oxide hybrid nanozymes is reported for magnetic enrichment and bioelectrocatalytic sensing of three prostate cancer (PCa) ctRNA biomarkers with high detection specificity and sensitivity (10 copies) over an ultrabroad dynamic range (five orders of magnitude). Furthermore, the feasibility of ctRNA analysis for pre- and post-cancer treatment MRD monitoring is demonstrated using PCa urinary liquid biopsy samples.
ARTICLE | doi:10.20944/preprints202207.0033.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: multiple myeloma; early mortality; blood plasma; circulating miRNA; hematological malignancies; molecular biomarker; multiparametric model; prognosissurvival
Online: 4 July 2022 (05:59:59 CEST)
Multiple myeloma (MM) is a hematological malignancy characterized by the clonal proliferation of plasma cells in the bone marrow (BM) microenvironment. Despite the progress made in treatment, some MM patients still die within the first year of diagnosis. Numerous studies investigating microRNA (miRNA) expression patterns suggest they may be good prognostic markers. The primary aim of this study was to analyze the expression of selected miRNAs in the serum of MM patients subsequently treated with bortezomib-based regimens and determine their potential to predict early mortality. The study was conducted in 69 prospectively-recruited patients with newly-diagnosed MM admitted to the Department of Hematology of the Copernicus Memorial Hospital, Lodz (Poland) between 2017 and 2021. Among them, 17 patients experienced death within 12 months of diagnosis. The expression of 31 selected miRNAs was determined using miRCURY LNA miRNA Custom PCR Panel. The obtained clinical data included patient characteristics on diagnosis, treatment regimen, response to treatment, and follow-up. Differential expression analysis found two miRNAs to be significantly downregulated in the early mortality group: hsa-miR-328-3p (fold change- FC: 0.72, p=0.0342) and hsa-miR-409-3p (FC: 0.49, p=0.0357). Univariate and multivariate logistic regression analyses were performed to assess the early mortality rate. The final model consisted of hsa-miR-409-3p, hsa-miR-328-3p, age and R-ISS 3. It yielded an area under the curve (AUC) of 0.863 (95%CI: 0.761-0.965) with 88.2% sensitivity and 77.5% specificity. Further external validation of our model is necessary to confirm its clinical value.
REVIEW | doi:10.20944/preprints202111.0357.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: non-destructive; biosensors; real-time detection; circulating tumor DNA (ctDNA); high sensitivity; Internet of Things
Online: 19 November 2021 (14:28:29 CET)
Early diagnosis and treatment have always been highly desired in the fight against cancer, and detection of circulating tumor DNA (ctDNA) has recently been touted as highly promising for early cancer screening. Consequently, the detection of ctDNA in liquid biopsy gains much attention in the field of tumor diagnosis and treatment, which has also attracted research interest from the industry. However, traditional gene detection technology is difficult to achieve low cost, real-time and portable measurement of ctDNA. Electroanalytical biosensors have many unique advantages such as high sensitivity, high specificity, low cost and good portability. Therefore, this review aims to discuss the latest development of biosensors for minimal-invasive, rapid, and real-time ctDNA detection. Various ctDNA sensors are reviewed with respect to their choices of receptor probes, detection strategies and figures of merit. Aiming at the portable, real-time and non-destructive characteristics of biosensors, we analyze their development in the Internet of Things, point-of-care testing, big data and big health.
REVIEW | doi:10.20944/preprints201804.0295.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: bone metastasis; tissue engineering; mesenchymal stem cells; osteoclast; osteoblast; dormancy; mouse models; circulating tumor cell
Online: 23 April 2018 (12:35:38 CEST)
Metastasis is the leading cause of cancer-related death and drives patient morbidity as well as healthcare costs. For several cancers, breast and prostate in particular, bone is the primary site of metastasis. Efforts to treat bone metastases have been stymied by a lack of models to study the progression and cellular players and signaling pathways driving bone metastasis. In this review, we examine the newly described and classic models of bone metastasis. Through the use of current in vivo, microfluidic and in silico computational models bone metastasis models we may eventually understand how cells escape the primary tumor and how these circulating tumor cells then home to and colonize the bone marrow. Further, future models may uncover how cell enter and escape dormancy to develop into overt metastases. Recreating the metastatic process will lead to the discovery of therapeutic targets for disrupting and treating bone metastasis.
ARTICLE | doi:10.20944/preprints201611.0105.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: circulating tumor cells; CTC, liquid biopsy; KRAS; colorectal cancer; EpCAM; CellSearch; IsoFlux; castPCR; intratumor heterogeneity
Online: 21 November 2016 (09:52:20 CET)
Circulating tumor cells (CTC) have shown to be prognostic in advanced colorectal cancer (advCRC), but their value for predicting response to treatment or as a source of molecular data is debated. We compared CellSearch® (Janssen Diagnostics, LLC) and IsoFluxTM (Fluxion Biosciences Inc, South San Francisco, CA) systems for the enumeration of CTC in patients with newly diagnosed advCRC (group 1; n=34). Using castPCRTM we studied KRAS status in CTC isolated with IsoFluxTM and compared it with that of the primary tumor in patients from group 1 and in KRAS wild-type (KRASWT) patients with progressive disease (group 2; n=22). Median number of CTC detected with CellSearch® (groups 1 and 2) was 1 (range: 0-78) and with IsoFluxTM (group 1) was 8 (range: 0-419), showing a modest correlation (r=0.345, P=0.036), which improved if lung metastases (r=0.805, P=0.016) or if lung and liver metastases were present (r=0.812, P=0.05). A Bland-Altman plot showed that the higher the number of CTC detected the larger the difference between both methods in favor of IsoFluxTM. After a median follow-up since CTC collection of 16 months (range: 1-30) CellSearch® ≥ 3 CTC (HR 2.77, 95% CI 0.77-9.95) and IsoFluxTM ≥ 11 CTC (HR 4.14, 95% CI 1.05-16.19) were established as the best cutoff points for predicting survival. Using castPCRTM we found KRAS mutations in CTC in 4 out of 8 patients from group 1 and in 2 out of 3 patients from group 2. None of these mutations were found in the primary tumor using standard methods, possibly reflecting intratumor heterogeneity or treatment selection pressure. We conclude that IsoFluxTM is more efficient than CellSearch® in the isolation of CTC in patients with advCRC, achieving, in a majority of cases, the established minimum of CTC for castPCRTM-based genetic analyses.
ARTICLE | doi:10.20944/preprints201608.0225.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: circular RNAs (circRNAs); circulating circRNA; type 2 diabetes mellitus (T2DM); pre-diabetes; microarray analysis; biomarker
Online: 29 August 2016 (13:37:38 CEST)
The purpose of current study was to investigate the expression characteristic of circular RNAs (circRNAs) in peripheral blood of type 2 diabetes mellitus (T2DM) patients and their potentials as diagnostic biomarkers for pre-diabetes and T2DM. In present study, the circRNAs in the peripheral blood from 6 healthy individuals and 6 T2DM patients were collected for microarray analysis. The results indicated that there were 489 differentially expressed circRNAs, of which 78 were upregulated and 411 were downregulated in the T2DM group. Then we selected 5 circRNAs as the candidate biomarkers under a stricter screening criteria and further verified them in another cohort (control group, n=20; pre-diabetes group, n =20; T2DM group; n=20). 3 of the 5 circRNAs presented upregulated expression in the experimental groups, including 2 circRNAs of the T2DM group that had higher expression than the pre-diabetes group. Hsa_circ_0054633 was identified to have the largest area value under the carve (AUC). In another independent cohort (control group, n=60; pre-diabetes group, n=63; T2DM group, n=64), the diagnostic capacity of hsa_circ_0054633 was tested. The results showed that the AUC for the diagnosis of pre-diabetes was 0.751(95% confidence interval=[0. 666-0.835], P＜0.001) while it was 0.793 ([0.716-0.871], P＜0.001) for the diagnosis of T2DM. After including the risk factors of T2DM, the AUC increased to 0.841 ([0.773-0.910], P <0.001) and 0.834 ([0.762-0.905], P <0.001), respectively. Hsa_circ_0054633 presented a certain diagnostic capability for pre-diabetes and T2DM.
REVIEW | doi:10.20944/preprints202010.0622.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: Cancerous Cell, Tumors, Cancer Metastasis, Circulating Tumor Cells (CTCs), Microfluidic Devices, lab-On-a-Chip (LOC), Lab-On-a-CD (LOCD)
Online: 29 October 2020 (15:38:54 CET)
Separation and interpretation of rebellious Circulating Tumor Cells (CTCs) originating from the primary tumor or cancer tissue plays a significant role in diagnostics, cancer progression analyses, suitable medicine exploration, and treatment proficiency examination. Cancer metastasis occurs when CTCs spread throughout the body and invade healthy tissues, leading to new tumors in that area. Although a dramatic rate of deaths begins from spreading CTCs around the body, valuable measures have been made to control their development. However, the first step is separating these harmful cells from the bloodstream and investigating their features. Having examined the characteristics of CTCs as cancer’s main strength, researchers can introduce complementary treatments that can affect cancerous cells without damaging the healthy cells. Therefore, according to their unique characteristics, numerous techniques have been established for continuous and fast separation and sorting of CTCs. Nevertheless, few separators enjoy the efficient performance and appropriate accuracy and can be produced in mass numbers due to the available fabrication equipment. Microfabrication advancements enable separators to combine the advantages of active and passive methods in a small-scale platform for probing individual cells and separation purposes. Reduction in reagents, sample volume, analysis time, and less harmfulness to patients are some of the motivations that encourage researchers to employ microfluidic instruments for CTCs separation from other blood cells over the last two decades. However, microfabrication limitations mean effective separators, and the diagnostic option they provide, are not readily available. Addressing these limitations requires optimizing the design and fabrication of separators such that they are reduced in their size and fabrication cost, while also maintaining high-throughput separating capability. The emergence of the Lab-On-a-Chip (LOC) and then Lab-On-a-CD (LOCD) technologies, having more inherent benefits than conventional microfluidic devices, has created new opportunities and become increasingly widespread in recent years. Evidence suggests that employing single methodologies or integrating approaches without sufficient understanding of potential outcomes is unlikely to result in successful diagnostic results. This paper contributes an extensive review of several separation systems, including fundamental theories and experimental details, and describes detailed operating principles and device performance.
ARTICLE | doi:10.20944/preprints202002.0003.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: drug repositioning/repurposing; dopamine transporter (DAT); benztropine; tumoroids; signal transducer and activator of transcription (STAT); circulating tumor cells (CTC); three-dimensional (3D) culture
Online: 3 February 2020 (03:16:54 CET)
Tumor growth, progression, and therapy resistance are crucial factors in the prognosis of cancer. Properties of three-dimensional tumor-like organoids (tumoroids) more closely resemble in vivo tumors compared to two-dimensionally cultured cells and are therefore effectively used for assays and drug screening. We here established a repurposed drug for novel anticancer research and therapeutics using a tumoroid-based screening system. We screened 6 pharmacologically active compounds by using an original tumoroid-based multiplex phenotypic screening system with matrix metalloproteinase 9 (MMP9) promoter-driven fluorescence reporter for the evaluation of both tumoroid formation and progression. The effects of one of the hit compounds were examined on tumor formation and progression in vitro and in vivo. Antiparkinson drug benztropine was the most effective compound uncovered by the screen. Benztropine significantly inhibited in vitro tumoroid formation, cancer cell survival, and MMP9 promoter activity. Benztropine also reduced the activity of oncogenic signaling transducers and trans-activators for MMP9, including STAT3, NF-κB, and β-catenin, and properties of cancer stem cells / cancer-initiating cells. Benztropine and GBR-12935 directly targeted the dopamine transporter DAT/SLC6A3, whose genetic alterations such as amplification were correlated with poor prognosis for cancer patients. Benztropine also inhibited tumor growth, circulating tumor cell (CTC) number, and rate of metastasis in a tumor allograft model in mice. In conclusion, we propose the repurposing of benztropine for anticancer research and therapeutics that can suppress tumor progression, CTC, and metastasis of aggressive cancers by reducing key pro-tumorigenic factors.
ARTICLE | doi:10.20944/preprints202201.0380.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Therapeutic biomarkers; circulating tumor cells; Immunocytochemistry; targeted therapy; Fluorescence in situ hybridization (FISH); Immune Checkpoint Inhibitors; Liquid Biopsy; Hormonal Treatments; Breast Cancer; Lung Cancer
Online: 25 January 2022 (11:31:05 CET)
Biomarker directed selection of targeted anti-neoplastic agents such as immune check-point inhibitors, small molecule inhibitors and monoclonal antibodies form an important aspect of cancer treatment. Immunohistochemistry (IHC) analysis of the tumor tissue is the method of choice to evaluate the presence of these biomarkers. However, a significant barrier to biomarker testing on tissue is the availability of an adequate amount of tissue and need for repetitive sampling due to tumor evolution. Also, tumor tissue testing is not immune to inter- and intra-tumor heterogeneity. We describe the analytical and clinical validation of a Circulating Tumor Cell (CTC) assay to accurately assess the presence of PD-L1 22C3 and PD-L1 28.8, ER, PR and HER2, from patients with solid tumors to guide the choice of suitable targeted therapies. Analytically, the test has high sensitivity, specificity, linearity and precision. Based on a blinded case control study, the clinical sensitivity and specificity for PD-L1 (22C3 and 28.8) was determined to be 90% and 100% respectively. The clinical sensitivity and specificity was 83% and 89% for ER; 80% and 94% for PR; 63% and 89% for HER2 (by ICC); and 100% and 92% for HER2 (by FISH), respectively. The performance characteristics of the test support its suitability and adaptability for routine clinical use.
COMMUNICATION | doi:10.20944/preprints202007.0709.v1
Subject: Biology, Other Keywords: intrinsic multi-drug resistance; acquired multi-drug resistance; circulating tumor cells; single cells; cell clusters; cell monolayer; multi-cellular spheroids; cytometry of reaction rate constant; ovarian cancer
Online: 30 July 2020 (09:01:50 CEST)
Does cell clustering influence intrinsic and acquired multi-drug resistance (MDR) differently? To address this question, we studied cultured monolayers (representing individual cells) and cultured spheroids (representing clusters) formed by drug-naïve (intrinsic MDR) and drug-exposed (acquired MDR) lines of ovarian cancer A2780 cells by cytometry of reaction rate constant (CRRC). MDR efflux was characterized by accurate and robust “cell number vs. MDR efflux rate constant (kMDR)” histograms. Both drug-naïve and drug-exposed monolayer cells presented unimodal histograms; the histogram of drug-exposed cells was shifted towards higher kMDR value suggesting greater MDR activity. Spheroids of drug-naïve cells presented a bimodal histogram indicating the presence of two subpopulations with different MDR activity. In contrast, spheroids of drug-exposed cells presented a unimodal histogram qualitatively similar to that of the monolayers of drug-exposed cells but with a moderate shift towards greater MDR activity. The observed greater effect of cell clustering on intrinsic than on acquired MDR can help guide the development of new therapeutic strategies targeting clusters of circulating tumor cells.