REVIEW | doi:10.20944/preprints202101.0582.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Breast cancer; CCN proteins; Metastasis; Tumorigenesis
Online: 28 January 2021 (12:38:09 CET)
CCNs are specific type of matricellular proteins, which are essential signaling molecules, and play multiple roles in multicellular eukaryotes. This family of proteins consists of six separate members in mammals. The architecture of CCN proteins is multimodular and comprises four distinct motifs. CCN proteins achieve their specific physiological functions by binding to integrin receptors. The CCN family has been implicated in both cure and disease with impacts on biological interactions, such as cell adhesion, chemotaxis and migration, mitogenesis, cell survival, angiogenesis, differentiation, tumorigenesis, immune functions, chondrogenesis, and wound healing. Breast cancer is the most commonly diagnosed cancer worldwide and the leading cause of cancer mortality among women triggered by atypical expression of CCNs. A favorable or unfavorable association between various CCNs has been reported in patients with breast carcinomas. Aberrant expression of CCN1 intensifies the proliferation of epithelial cells that line the lobes and ducts of the breast. Evidence also shows that the expression of CCN2 can ameliorate tumor growth and metastasis. However, CCN3 (NOV), CCN5 (WISP-2), and CCN6 (WISP-3) are consistent with neoplastic development and metastasis repression. Particular CCN members can develop tumors and cancer progression, whereas others can competitively counter the processes. Several studies have been conducted on CCN proteins and cancer in recent years. In our study, we intend to provide an overview of those research works while keeping breast carcinoma on focus. We believe that the importance of the CCN protein family in breast cancer should be reconsidered.
ARTICLE | doi:10.20944/preprints202109.0394.v1
Subject: Life Sciences, Immunology Keywords: EGF; LUBAC; HOIP; PKP2; linear ubiquitin; NF-kB; tumorigenesis
Online: 22 September 2021 (22:51:26 CEST)
Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that instigates several signaling cascades, including the NF-kB signaling pathway, to induce cell differentiation and proliferation. Overexpression and mutations of EGFR are found in up to 30% of solid tumors and correlate with a poor prognosis. Although it is known that EGFR-mediated NF-kB activation is involved in tumor development, the signaling axis is not well elucidated. Here, we found that PKP2 and the LUBAC complex were required for EGFR-mediated NF-kB activation. Upon EGF stimulation, EGFR recruited PKP2 to the plasma membrane, and PKP2 bridged HOIP, the catalytic E3 ubiquitin ligase in the LUBAC, to the EGFR complex. The recruitment activated the LUBAC complex and the linear ubiquitination of NEMO, leading to IkB phosphorylation and subsequent NF-kB activation. Furthermore, EGF-induced linear ubiquitination was critical for tumor cell proliferation and tumor development. Knockout of HOIP impaired EGF-induced NF-kB activity and reduced cell proliferation. HOIP knockout also abrogated the growth of A431 epidermal xenograft tumors in nude mice by more than 70%. More importantly, the HOIP inhibitor, HOIPIN-8, inhibited EGFR-mediated NF-kB activation and cell proliferation of A431, MCF-7, and MDA-MB-231 cancer cells. Overall, our study reveals a novel linear ubiquitination signaling axis of EGFR, and perturbation of HOIP E3 ubiquitin ligase activity is potential targeted cancer therapy.
REVIEW | doi:10.20944/preprints202110.0013.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: uveal melanoma; tumorigenesis; molecular classification; targeted therapy; immune checkpoint; tumor heterogeneity
Online: 1 October 2021 (11:54:23 CEST)
Uveal melanoma (UM) is characterized by relatively few, highly incident molecular alterations and their association with metastatic risk is deeply understood. Nevertheless, this knowledge has so far not led to innovate therapies for the successful treatment of UM metastases or for adjuvant therapy, leaving survival after diagnosis of metastatic UM almost unaltered in decades. The driver mutations of UM, mainly in the G-protein genes GNAQ and GNA11, activate the MAP-kinase pathway as well as the YAP/TAZ pathway. At present, there are no drugs that target the latter and this likely explains the failure of MEK-inhibitors. Immune checkpoint blockers, despite the game changing effect in cutaneous melanoma (CM) show only marginal effects in UM probably because of the low mutational burden of 0.5 per megabase and the unavailability of antibodies targeting the main immune checkpoint active in UM. The highly pro-tumorigenic microenvironment of UM also contributes to therapy resistance. However, T-cell redirection by a soluble T cell receptor that is fused to an anti-CD3 single-chain variable fragment, local, liver specific therapy, new immune checkpoint blockers and YAP/TAZ specific drugs give new hope to repeat the success of innovative therapy obtained for CM.
ARTICLE | doi:10.20944/preprints202208.0413.v1
Subject: Life Sciences, Molecular Biology Keywords: translation initiation; canonical and noncanonical translation initiation codons; protein translation; oncogene; oncogenesis; tumorigenesis; cancer
Online: 24 August 2022 (05:30:03 CEST)
Ribosome profiling and mass spectroscopy have identified canonical and noncanonical translation initiation codons (TICs) that are upstream of the main translation initiation site and used to translate oncogenic proteins. Here, we use a Kozak Similarity Score algorithm to find that nearly all of these TICs have flanking nucleotides closely matching the Kozak sequence. Remarkably, the nucleotides flanking alternative noncanonical TICs are frequently closer to the Kozak sequence than the nucleotides flanking TICs used to translate the gene’s main protein. Of note, the 5’ untranslated region (5‘UTR) of cancer-associated genes with an upstream TIC tend to be significantly longer than the same region in genes not associated with cancer. The presence of a longer than typical 5’UTR increases the likelihood of ribosome binding to upstream noncanonical TICs, and may be a distinguishing feature of a number of genes overexpressed in cancer. Noncanonical TICs that are located in the 5’UTR, although thought disadvantageous and suppressed by evolution, may translate oncogenic proteins because of their flanking nucleotides
ARTICLE | doi:10.20944/preprints202101.0490.v1
Subject: Biology, Anatomy & Morphology Keywords: CD44; Cancer Stem Cells; Tumorigenesis; Drug Resistance; Immune Markers; Epithelial to Mesenchymal Transition; Therapeutic Targeting
Online: 25 January 2021 (12:23:49 CET)
One of the most used markers of cancer stem cells in several cancers, including colorectal cancer and breast cancer, is CD44. CD44 is a glycoprotein that traverses the cell membrane and binds to many ligands including hyaluronan resulting in activation of signaling cascades. Several reports have shown conflicting data on the expression of CD44 and that the expression depends on modes of investigations and subtypes of cancers. In addition, the correlation between CD44 expression and drug resistance, immune infiltration, EMT, metastasis and patients prognosis in several cancer types remains unclear. This study investigated CD44 expression in several cancers and explored its relationship with tumorigenesis using various publicly available databases, including The Cancer Genome Atlas, GEPIA, Oncomine, Genomics of Drug Sensitivity in Cancer and Tumor Immune Estimation Resource. Our analysis reveals that CD44 is differentially expressed in different cancers. CD44 expression is significantly associated with cancer patients’ survival in gastric, pancreatic and colorectal cancers. In addition, CD44 expression is closely linked with immune infiltration and immune suppressive features in pancreatic, colon adenocarcinoma and stomach cancer. High CD44 expression was significantly correlated with the expression of drug resistance-, EMT- and metastasis- linked genes. Tumors expressing high CD44 have higher mutation burden and afflict older patients than tumors expressing low CD44. Cell lines expressing high CD44 are more resistant to anti-cancer drugs compared to those expressing low CD44. Protein-protein interaction investigations and functional enrichment analysis showed that CD44 interacts with gene products related to cell-substrate adhesion, migration, platelet activation, and cellular response to stress. KEGG pathway analysis revealed that these genes play key roles in biological adhesion, cell component organization, locomotion, G-α-signaling and the response to stimulus. Overall, this investigation reveals that CD44 play significant roles in tumorigenesis, can be used as a prognostic biomarker in several cancers and can be therapeutically targeted in cancer therapy.
REVIEW | doi:10.20944/preprints202010.0514.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Single-Nucleotide Polymorphisms; Point Mutation; Chemokines; T-cells; Viral Infection; Tumorigenesis; T-cell Surface; Immune Response
Online: 26 October 2020 (11:08:40 CET)
C-C Chemokine receptor type 5 (CCR5) is expressed on the CD4 T cell surface where CXCR4 and CCR5 expressions are controlled differently during the activation of T cells and with the binding of interleukin type-2 (IL-2). IL-2 can upregulate CCR1 and CCR2 in CD45R01 T cells and increase the T lymphocyte chemotaxis toward CC-chemokines. CD4+ T cells are either apart of the T helper 1 or Th1 lymphocytes that release interferon gamma (IFNγ) and lymphotoxin that provide cellular immunity to internal pathogens and T helper cells type 2 (Th2), which secrete interleukins 4 and 5 (IL-4 and IL-5). IL-4 and IL-5 cause an allergic and humoral immune response to parasites. Th2 lymphocytes use CCR3 chemokine receptors. CCR5 and CXCR3 chemokine receptors are specific for CD4+ Th1 and Th2 lymphocytes. CCR5Δ32 is a 32-base-pair deletion of the CCR5 gene. CCR5 is a co-receptor for the entrance of the human immunodeficiency virus-1 (HIV-1). CCR5Δ32 creates a malfunction of the CCR5 protein that can prevent HIV-1 infection. However, the CCR5Δ32 32-base-pair deletion is not prevalent and predominant in many populations worldwide and there also exist more genetic variations of CCR5 known as CCR5-SNPs. An alternative polymorphism was identified based on the CCR5 gene that was identified as a A to G (A/G) point mutation. This point mutation is located at the 59029 locus on the promoter that lowers the expression rate of CCR5. Gurdol et al. found activity at the promoter of CCR5/590029G was 45% lesser than the CCR5/59029A. The genetic variations of CCR5 SNPs also include: 2459G>SNP of CCR5, C101X, CCR5 gene position at -2273, and the A to G SNP mutation found in two South African blacks. Therefore, more studies are needed to find more and varied chemokine polymorphisms that are present in many diverse populations in the world. The aim of this literature review is to describe the immense impact of CCR5 SNP mutations on viral infection susceptibility, on the pathogenesis of chronic conditions, to endorse the increased discovery of more novel CCR5 SNPs, and to show the significant potential of anti-CCR5 therapies to treat multiple diseased conditions.
ARTICLE | doi:10.20944/preprints202003.0371.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: matrix metalloproteinase 3 (MMP3); extracellular vesicles (EVs); tumoroid; tumor organoid; tumorigenesis; three-dimensional (3D) culture system
Online: 25 March 2020 (05:25:09 CET)
The tumor organoid (tumoroid) model in three-dimensional (3D) culture systems has been developed to reflect more closely the in vivo tumors than 2D-cultured tumor cells. Notably, extracellular vesicles (EVs) are efficiently collectible from the culture supernatant of gel-free tumoroids. Matrix metalloproteinase (MMP) 3 is a multi-functional factor playing crucial roles in tumor progression. However, roles of MMP3 within tumor growth and EVs have not unveiled. Here, we investigated the protumorigenic roles of MMP3 on integrities of tumoroids and EVs. We generated MMP3-knockout (KO) cells using the CRISPR/Cas9 system from rapidly metastatic LuM1 tumor cells. Moreover, we established fluorescent cell lines with palmitoylation signal-fused fluorescent proteins (tdTomato and enhanced GFP). Then we confirmed the exchange of EVs between cellular populations and tumoroids. LuM1-tumoroids released large EVs (300-1000 nm) and small EVs (50-200 nm) while the knockout of MMP3 resulted in the additional release of broken EVs from tumoroids. The loss of MMP3 leads to a significant reduction in tumoroid size and to the development of the necrotic area within tumoroids. MMP3 and CD9 (a category-1 EV marker tetraspanin protein) were significantly down-regulated in MMP3-KO cells and their EV fraction. These weakened phenotypes by MMP3 KO were markedly rescued by the addition of MMP3-rich EVs or conditioned medium (CM) collected from LuM1-tumoroids, which caused a dramatic rise in the expression of MMP3, CD9, and Ki-67 (a marker of proliferating cells) in the MMP3-null/CD9-low tumoroids. Notably, MMP3 enriched in tumoroids-derived EVs and CM deeply penetrated into recipient MMP3-KO tumoroids, resulting in a remarkable enlargement of solid tumoroids, while MMP3-null EVs did not. These data demonstrate that EVs can mediate molecular transfer of MMP3 resulting in increasing the proliferation and CD9+ tumorigenesis, indicating crucial roles of MMP3 in tumor progression.
REVIEW | doi:10.20944/preprints201806.0163.v2
Subject: Life Sciences, Molecular Biology Keywords: SIRT6, Diabetes, Gluconeogenesis, Cancer, Aging, Heart Disease, Pharmacological SIRT6 Inhibitor, Cardiac Hypertrophy, Tumorigenesis, Neurodegeneration, Neurodegenerative Diseases, AD
Online: 29 August 2018 (13:04:23 CEST)
SIRT6 is a NAD+ dependent enzyme and stress response protein that has sparked the curiosity of a plethora of researchers in different branches of the biomedical sciences. A unique member of the known Sirtuin family, SIRT6 has several different functions in several different molecular pathways related to DNA repair, glycolysis, gluconeogenesis, tumorigenesis, neurodegeneration, cardiac hypertrophic responses and so on. Only in recent times however did the potential usefulness of SIRT6 come to light as we learned more about its biochemical activity, regulation, biological roles and structure . Even until very recently, SIRT6 was known more for chromatin signaling but being a nascent topic of study, more information has been ascertained and its potential involvement in major human diseases namely, diabetes, cancer, neurodegenerative diseases and heart disease has been demonstrated. It is pivotal to explore the mechanistic workings of SIRT6 since future research may hold the key to engendering strategies, involving SIRT6, that may have significant implications for human health and expand upon possible treatment options. In this review, we are primarily concerned with exploring the latest understanding of SIRT6 and how it can alter the course of several life-threatening diseases that cripple today’s society such as processes related to aging, cancer, neurodegenerative diseases, heart disease and diabetes. In addition, SIRT6 has shown to be involved in liver disease, inflammation and bone related issues but more emphasis is given to the former. Lastly, any recent promising pharmacological investigations and study of potential therapeutic targets are also delineated in this review.
REVIEW | doi:10.20944/preprints202208.0203.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: neural induction; embryogenesis; tumorigenesis; conjoined twin; Spemann organizer; node; neural default model; neural stemness; tumorigenicity; pluripotency; epithelial-mesenchymal transition; tumor microenvironment
Online: 10 August 2022 (12:10:36 CEST)
Some concepts/hypotheses have been proposed to explain the general rules behind the complexity of tumorigenesis. Characterization of the property of cancer cells and neural stem cells indicates that neural stemness underlies tumorigenicity and pluripotency, leading to the proposal that tumorigenesis represents a process of progressive loss of original cell identity and gain of neural stemness. This reminds of a most fundamental process required for the development of the nervous system and body axis during embryogenesis, i.e., embryonic neural induction. The principle of neural induction is that, in response to extracellular signals that are secreted by the Spemann-Mangold organizer in amphibians or the node in mammals and inhibit epidermal fate in ectoderm, the ectodermal cells assume the neural default fate and turn into neuroectodermal cells. These cells further differentiate into the nervous system and also some non-neural cells via interaction with adjacent tissues. Failure in neural induction leads to failure of embryogenesis, and ectopic neural induction due to ectopic organizer or node activity or activation of embryonic neural genes causes a formation of secondary body axis or conjoined twins. A similar principle underlies tumorigenesis. Increasing evidence has demonstrated that the core property of cancer cells is neural stemness. Therefore, cancer cells are cells with the loss of original cell identity and gain of neural stemness, and consequently tumorigenicity and pluripotency, due to various intra-/extracellular insults in postnatal animals. Unlike that pluripotent cells (embryonic pluripotent cells, neural stem cells and cancer cells) can differentiate and integrate into embryonic development, cancer cells are capable of self-renewal and differentiation, but cannot integrate into normal tissues in a 2 postnatal animal, ultimately leading to tumor formation. Neural induction and the unique property of neural stemness provide an inclusive explanation for embryogenesis, conjoined twin formation and tumorigenesis. Based on these findings, I discuss about some confusion in cancer research, e.g., epithelial-mesenchymal transition, and propose to distinguish the causality and associations, and the causal and supporting factors involved in tumorigenesis, and suggest revisiting the focus of cancer research. Integration of evidence from developmental and cancer biology indicates that neural stemness determines tumorigenicity and pluripotency, and neural induction drives embryogenesis in gastrulating embryos but a similar process drives tumorigenesis in a postnatal animal.
REVIEW | doi:10.20944/preprints202012.0122.v1
Subject: Life Sciences, Biochemistry Keywords: neural stemness; neural stem/progenitor cell; tumor-initiating cell; neural ground state; neural default model; differentiation potential; tumorigenicity; tumorigenesis; evo-devo
Online: 7 December 2020 (07:02:34 CET)
Tumorigenesis is a complex biological phenomenon that includes extensive genetic and phenotypic heterogeneities and complicated regulatory mechanisms. In the recent few years, our studies demonstrate that tumor-initiating cells are similar to neural stem/progenitor cells in regulatory networks, tumorigenicity and pluripotent differentiation potential. In the review, I will make further discussion on these observations and propose a rule of cell biology by integrating these findings with evidence from developmental biology, tumor biology and evolution, which suggests that neural stemness underlies two coupled cell properties, tumorigenicity and pluripotent differentiation potential. Tumorigenicity and phenotypic heterogeneity in tumor is a result of acquirement of neural stemness in cells. The neural stemness property of tumor-initiating cells can hopefully integrate different concepts/hypotheses underlying tumorigenesis. Neural stem cells/neural progenitors and tumor-initiating cells share regulatory networks; both exhibit neural stemness, tumorigenicity and differentiation potential; both are dependent on expression or activation of ancestral genes (the atavistic effect); both rely primarily on aerobic glycolytic metabolism; both can differentiate into various cells or tissues that are derived from three germ layers, resembling severely disorganized or more severely degenerated process of embryonic development; both are enriched in long genes with more splice variants that provide more plastic scaffolds for cell differentiation, etc. The property of neural stemness might be a key point to understand tumorigenesis and pluripotent differentiation potential, and possibly explain certain pathological observations in tumors that have been inexplicable. Therefore, behind the complexity of tumorigenesis might be a general rule of cell biology, i.e., neural stemness represents the ground state of cell tumorigenicity and pluripotent differentiation potential.
HYPOTHESIS | doi:10.20944/preprints202102.0499.v1
Subject: Life Sciences, Biochemistry Keywords: Acute and Chronic Inflammation; Bioenergetics; Constituent and Inducible Receptors; Fetus; Genomics; Glycolysis; Immunity; Immune compromised; Immune disorders; Infant; Inheritance; Mitochondrial; Newborn; Placenta; Power within; Power without; Sovereignty; Throphoblast; Tumorigenesis; Tumoricidal; Vaccines; Yin-Yang
Online: 23 February 2021 (07:59:36 CET)
A parallel between defense powers of sovereign nations and effective immunity that guards health is relevant to demonstrate vulnerability of immune system under external forces (vaccines, drugs). History demonstrated that sovereignty (power within) of small nations often threatened or destroyed by military might of powerful nations (power without) who use false-flags and propaganda for motives that are financial-control-driven. Similarly, we propose that body’s complex immune neuroplasticity (power within, adaptive, horizontal) is stretched-thin and weakened by the external forces, particularly by vaccination of the unborn/newborn or immune-compromised individuals. Validity of genomics (innate, perpendicular) as origins of ‘hereditary’ diseases (eg, allergies, diabetes, cancers) that for a century dominated research and treatment is also challenged. In conclusion, we propose that the pressure/power from within creates life with potential to sustain health, while the pressure/power from without, weaken and destroy life.