Transmembrane protein TMEM230, regulator of metalloproteins and motor proteins in gliomas and gliosis.

Glial cells provide physical and chemical support and protection for neurons and for the extracellular compartments of neural tissue through secretion of soluble factors, insoluble scaffolds, and vesicles. Additionally, glial cells have regenerative capacity by remodeling their physical microenvironment and changing physiological properties of diverse cell types in their proximity. Various types of aberrant glial and macrophage cells are associated with human diseases, disorders, and malignancy. We previously demonstrated that transmembrane protein, TMEM230 has tissue revascularization and regenerating capacity by its ability to secrete pro-angiogenic factors and metalloproteinases, inducing endothelial cell sprouting and channel formation. In healthy normal neural tissue, TMEM230 is predominantly expressed in glial and marcophate cells, suggesting a prominent role in neural tissue homeostasis. TMEM230 regulation of the endomembrane system was supported by co-expression with RNASET2 (lysosome, mitochondria, and vesicles) and STEAP family members (Golgi complex). Intracellular trafficking and extracellular secretion of glial cellular components are associated with endocytosis, exocytosis and phagocytosis mediated by motor proteins. Trafficked components include metalloproteins, metalloproteinases, glycans, and glycoconjugate processing and digesting enzymes that function in phagosomes and vesicles to regulate normal neural tissue microenvironment, homeostasis, stress response, and repair following neural tissue injury or degeneration. Aberrantly high sustained levels TMEM230 promotes metalloprotein expression, trafficking and secretion which contribute to tumor associated infiltration and hypervascularization of high tumor grade gliomas. Following injury of the central nervous or peripheral systems, transcient regulated upregulation of TMEM230 promotes tissue wound healing, remodeling and revascularization by activating glial and macrophage generated microchannels/microtubules (referred to as vascular mimicry) and blood vessel sprouting and branching. Our results support that TMEM230 may act as a master regulator of motor protein mediated trafficking and compartmentalization of a large class of metalloproteins in gliomas and gliosis.

Single-cell transcriptomic analysis to identify endomembrane regulation of metalloproteins and motor proteins in autoimmunity.

TMEM230 promotes antigen processing, trafficking, and presentation by regulating the endomembrane system of membrane bound organelles (lysosomes, proteosomes and mitochondria) and phagosomes. Activation of the immune system requires trafficking of various cargos between the endomembrane system and cell plasma membrane. The Golgi apparatus is the hub of the endomembrane system and essential for the generation, maintenance, recycling, and trafficking of the components of the endomembrane system itself and immune system. Intracellular trafficking and secretion of immune system components depend on mitochondrial metalloproteins for ATP synthesis that powers motor protein transport of endomembrane cargo. Glycan modifying enzyme genes and motor proteins are essential for the activation of the immune system and trafficking of antigens between the endomembrane system and the plasma membrane. Recently, TMEM230 was identified as co-regulated with RNASET2 in lysosomes and with metalloproteins in various cell types and organelles, including mitochondria in autoimmune diseases. Aberrant metalloproteinase secretion by motor proteins is a major contributor to tissue remodeling of synovial membrane and joint tissue destruction in rheumatoid arthritis (RA) by promoting infiltration of blood vessels, bone erosion, and loss of cartilage by phagocytes. In this study, we identified that specific glycan processing enzymes are upregulated in certain cell types (fibroblast or endothelial cells) that function in destructive tissue remodeling in rheumatoid arthritis compared to osteoarthritis (OA). TMEM230 was identified as a regulator in the secretion of metaloproteinases and heparanase necessary tissue remodeling in OA and RA. In dendritic (DC), natural killer and T cells, TMEM230 was expressed at low or no levels in RA compared to OA. TMEM230 expression in DC likely is necessary for regulatory or helper T cells to maintain tolerance to self-antigens and prevent susceptibility to autoimmune disease. To identify how TMEM230 and the endomembrane system contribute to autoimmunity we investigated, glycan modifying enzymes, metalloproteinases and motor protein genes co-regulated with or regulated by TMEM230 in synovial tissue by analyzing published single cell transcriptomic datasets from RA patient derived synovial tissue.

Long-term culture of patient-derived mammary organoids in non-biogenic electrospun scaffolds for identifying metalloprotein and motor protein activities in aging and senescence.

We recently identified TMEM230 as a master regulator of the endomembrane system of cells. TMEM230 expression is necessary for promoting motor protein dependent intracellular trafficking of metalloproteins for cellular energy production in mitochondria. TMEM230 is also required for transport and secretion of metalloproteinases for autophagy and phagosome dependent clearance of misfolded proteins, defective RNAs and damaged cells, activities that decline with aging. This suggests that aberrant levels of TMEM230 may contribute to aging and regain of proper levels may have therapeutic applications. The components of the endomembrane system include the Golgi complex, other membrane bound organelles, and secreted vesicles and factors. Secreted cellular components modulate immune response and tissue regeneration in aging. Upregulation of intracellular packaging, trafficking and secretion of endosome components while necessary for tissue homeostasis and normal wound healing, also promote secretion of pro-inflammatory and pro-senescence factors. We recently determined that TMEM230 is co-regulated with trafficked cargo of the endomembrane system, including lysosome factors such as RNASET2. Normal tissue regeneration (in aging), repair (following injury) and aberrant destructive tissue remodeling (in cancer or autoimmunity) likely are regulated by TMEM230 activities of the endomembrane system, mitochondria and autophagosomes. The role of TMEM230 in aging is supported by its ability to regulate the pro-inflammatory secretome and senescence-associated secretory phenotype in tissue cells of patients with advanced age and chronic disease. Identifying secreted factors regulated by TMEM230 in young patients and patients of advanced age will facilitate identification of aging associated targets that aberrantly promote, inhibit or reverse aging. Ex situ culture of patient derived cells for identifying secreted factors in tissue regeneration and aging provides opportunities in developing therapeutic and personalized medicine strategies. Identification and validation of human secreted factors in tissue regeneration requires long-term stabile scaffold culture conditions that are different from those previously reported for cell lines used as cell models for aging. We describe a 3 dimensional (3D) platform utilizing non-biogenic and non-labile poly ε-caprolactone scaffolds that supports maintenance of long-term continuous cultures of human stem cells, in vitro generated 3D organoids and patient derived tissue. Combined with animal component free culture media, non-biogenic scaffolds are suitable for proteomic and glycobiological analyses to identify human factors in aging. Applications of electrospun nanofiber technologies in 3D cell culture allow for ex situ screening and the development of patient personalized therapeutic strategies and predicting their effectiveness in mitigating or promoting aging.

Endometriosis-Associated Ovarian Cancer: From Molecular Pathologies to Clinical Relevance.

Endometriosis is a chronic condition affecting reproductive-aged women, characterized by the growth of ectopic endometrial tissue. Despite being benign, endometriosis is associated with an increased risk of certain cancers, including endometriosis-associated ovarian cancer (EAOC). Ovarian cancer is rare, but more common in women with endometriosis, particularly endometrioid and clear-cell carcinomas. Factors such as hormonal imbalance, reproductive history, environmental exposures, and genetic predisposition contribute to the malignant transformation of endometriosis. Thus, understanding potential risk factors causing malignancy is crucial. Over the past few decades, various genetic mutations, microRNAs, as well as tumor microenvironmental factors have been identified, impacting pathways like PI3K/AKT/mTOR, DNA repair mechanisms, oxidative stress, and inflammation. Thus, this review aims to summarize molecular studies involved in EAOC pathogenesis as potential therapeutic targets. However, further research is needed to better understand the molecular and environmental factors driving EAOC development, to target the susceptibility of endometriotic lesions to malignant progression, and to identify effective therapeutic strategies.

Transmembrane Protein TMEM230, Regulator of Glial Cell Vascular Mimicry and Endothelial Cell Angiogenesis in High-Grade Heterogeneous Infiltrating Gliomas and Glioblastoma.

High-grade gliomas (HGGs) and glioblastoma multiforme (GBM) are characterized by a heterogeneous and aggressive population of tissue-infiltrating cells that promote both destructive tissue remodeling and aberrant vascularization of the brain. The formation of defective and permeable blood vessels and microchannels and destructive tissue remodeling prevent efficient vascular delivery of pharmacological agents to tumor cells and are the significant reason why therapeutic chemotherapy and immunotherapy intervention are primarily ineffective. Vessel-forming endothelial cells and microchannel-forming glial cells that recapitulate vascular mimicry have both infiltration and destructive remodeling tissue capacities. The transmembrane protein TMEM230 (C20orf30) is a master regulator of infiltration, sprouting of endothelial cells, and microchannel formation of glial and phagocytic cells. A high level of TMEM230 expression was identified in patients with HGG, GBM, and U87-MG cells. In this study, we identified candidate genes and molecular pathways that support that aberrantly elevated levels of TMEM230 play an important role in regulating genes associated with the initial stages of cell infiltration and blood vessel and microchannel (also referred to as tumor microtubule) formation in the progression from low-grade to high-grade gliomas. As TMEM230 regulates infiltration, vascularization, and tissue destruction capacities of diverse cell types in the brain, TMEM230 is a promising cancer target for heterogeneous HGG tumors.

Nuclear localization of heparanase 2 (Hpa2) attenuates breast carcinoma growth and metastasis.

Unlike the intense research effort devoted to exploring the significance of heparanase in cancer, very little attention was given to Hpa2, a close homolog of heparanase. Here, we explored the role of Hpa2 in breast cancer. Unexpectedly, we found that patients endowed with high levels of Hpa2 exhibited a higher incidence of tumor metastasis and survived less than patients with low levels of Hpa2. Immunohistochemical examination revealed that in normal breast tissue, Hpa2 localizes primarily in the cell nucleus. In striking contrast, in breast carcinoma, Hpa2 expression is not only decreased but also loses its nuclear localization and appears diffuse in the cell cytoplasm. Importantly, breast cancer patients in which nuclear localization of Hpa2 is retained exhibited reduced lymph-node metastasis, suggesting that nuclear localization of Hpa2 plays a protective role in breast cancer progression. To examine this possibility, we engineered a gene construct that directs Hpa2 to the cell nucleus (Hpa2-Nuc). Notably, overexpression of Hpa2 in breast carcinoma cells resulted in bigger tumors, whereas targeting Hpa2 to the cell nucleus attenuated tumor growth and tumor metastasis. RNAseq analysis was performed to reveal differentially expressed genes (DEG) in Hpa2-Nuc tumors vs. control. The analysis revealed, among others, decreased expression of genes associated with the hallmark of Kras, beta-catenin, and TNF-alpha (via NFkB) signaling. Our results imply that nuclear localization of Hpa2 prominently regulates gene transcription, resulting in attenuation of breast tumorigenesis. Thus, nuclear Hpa2 may be used as a predictive parameter in personalized medicine for breast cancer patients.

A biological guide to glycosaminoglycans: current perspectives and pending questions.

Mammalian glycosaminoglycans (GAGs), except hyaluronan (HA), are sulfated polysaccharides that are covalently attached to core proteins to form proteoglycans (PGs). This article summarizes key biological findings for the most widespread GAGs, namely HA, chondroitin sulfate/dermatan sulfate (CS/DS), keratan sulfate (KS), and heparan sulfate (HS). It focuses on the major processes that remain to be deciphered to get a comprehensive view of the mechanisms mediating GAG biological functions. They include the regulation of GAG biosynthesis and postsynthetic modifications in heparin (HP) and HS, the composition, heterogeneity, and function of the tetrasaccharide linkage region and its role in disease, the functional characterization of the new PGs recently identified by glycoproteomics, the selectivity of interactions mediated by GAG chains, the display of GAG chains and PGs at the cell surface and their impact on the availability and activity of soluble ligands, and on their move through the glycocalyx layer to reach their receptors, the human GAG profile in health and disease, the roles of GAGs and particular PGs (syndecans, decorin, and biglycan) involved in cancer, inflammation, and fibrosis, the possible use of GAGs and PGs as disease biomarkers, and the design of inhibitors targeting GAG biosynthetic enzymes and GAG-protein interactions to develop novel therapeutic approaches.

Management of Uterine Fibroids and Sarcomas: The Palermo Position Paper.

BACKGROUND: Uterine fibroids are benign monoclonal tumors originating from the smooth muscle cells of the myometrium, constituting the most prevalent pathology within the female genital tract. Uterine sarcomas, although rare, still represent a diagnostic challenge and should be managed in centers with adequate expertise in gynecological oncology. OBJECTIVES: This article is aimed to summarize and discuss cutting-edge elements about the diagnosis and management of uterine fibroids and sarcomas. METHODS: This paper is a report of the lectures presented in an expert meeting about uterine fibroids and sarcomas held in Palermo in February 2023. OUTCOME: Overall, the combination of novel molecular pathways may help combine biomarkers and expert ultrasound for the differential diagnosis of uterine fibroids and sarcomas. On the one hand, molecular and cellular maps of uterine fibroids and matched myometrium may enhance our understanding of tumor development compared to histologic analysis and whole tissue transcriptomics, and support the development of minimally invasive treatment strategies; on the other hand, ultrasound imaging allows in most of the cases a proper mapping the fibroids and to differentiate between benign and malignant lesions, which need appropriate management. CONCLUSIONS AND OUTLOOK: The choice of uterine fibroid management, including pharmacological approaches, surgical treatment, or other strategies, such as high-intensity focused ultrasound (HIFU), should be carefully considered, taking into account the characteristics of the patient and reproductive prognosis.

Compartmental Syndecan-1 (CD138) expression as a novel prognostic marker in triple-negative metaplastic breast cancer.

BACKGROUND: Metaplastic breast cancer (MpBC) is rare, aggressive, and mostly triple-negative (TN) subtype of BC. We aimed to investigate the potential prognostic significance of Syndecan-1 (SDC1/CD138) expression in this unique tumor. METHODS: Archived charts of 50 TNBC patients [21 MpBC and 29 invasive ductal carcinoma (IDC)] were retrospectively evaluated. Corresponding paraffin blocks were used for immunohistochemical (IHC) staining of SDC1. Compartmental (epithelial membranous, stromal, and cytoplasmic) staining scores were expressed in quartiles (Q) and correlated with disease-free survival (DFS) and overall survival (OS). RESULTS: The median follow-up period was 54.6 months (range: 2.2-112.7). MpBC patients showed significantly worse DFS and OS than IDC (p = 0.007 and 0.004, respectively). MpBC demonstrated significantly higher Q4 stromal and membranous SDC1 compared to IDC (p = 0.016 and 0.021, respectively), whereas IDC exhibited significantly higher cytoplasmic Q4 SDC1 than MpBC (p = 0.015). Stromal Q4 SDC1 expression was found to be an independent factor associated with MpBC relative to IDC (OR: 6.7, 95% CI: 1.24-36.90; p = 0.028). Stromal Q4 SDC1 expression was also an independent prognostic parameter for worse DFS and OS compared to Q1-3 in the whole cohort (HR: 4.2, 95% CI: 1.6-10.5; p = 0.003 and HR: 5.8; 95% CI: 2.2-15.3; p < 0.001, respectively). In MpBC, cytoplasmic Q1-3 SDC1 expression was an independent prognostic indicator for worse OS compared with their IDC counterparts (HR: 2.837, 95% CI: 1.048-7.682; p = 0.04). CONCLUSION: This study suggests, for the first time, that differential expression and localization of SDC1 may contribute to the pathogenesis and prognosis of TN-MpBC. Therefore, targeting SDC1 (CD138) could emerge as a novel therapeutic approach for this devastating disease.

The Musashi RNA-binding proteins in female cancers: insights on molecular mechanisms and therapeutic relevance.

RNA-binding proteins have increasingly been identified as important regulators of gene expression given their ability to bind distinct RNA sequences and regulate their fate. Mounting evidence suggests that RNA-binding proteins are involved in the onset and progression of multiple malignancies, prompting increasing interest in their potential for therapeutic intervention.The Musashi RNA binding proteins Musashi-1 and Musashi-2 were initially identified as developmental factors of the nervous system but have more recently been found to be ubiquitously expressed in physiological tissues and may be involved in pathological cell behavior. Both proteins are increasingly investigated in cancers given dysregulation in multiple tumor entities, including in female malignancies. Recent data suggest that the Musashi proteins serve as cancer stem cell markers as they contribute to cancer cell proliferation and therapy resistance, prompting efforts to identify mechanisms to target them. However, as the picture remains incomplete, continuous efforts to elucidate their role in different signaling pathways remain ongoing.In this review, we focus on the roles of Musashi proteins in tumors of the female - breast, endometrial, ovarian and cervical cancer - as we aim to summarize current knowledge and discuss future perspectives.

Dysregulated Stem Cell Markers Musashi-1 and Musashi-2 are Associated with Therapy Resistance in Inflammatory Breast Cancer.

BACKGROUND AND AIM: While preliminary evidence points to pro-tumorigenic roles for the Musashi (MSI) RNA-binding proteins Musashi-1 (MSI1) and Musashi-2 (MSI2) in some breast cancer subtypes, no data exist for inflammatory breast cancer (IBC). METHODS: MSI gene expression was quantified in IBC SUM149PT cells. We then used small interfering RNA-based MSI1 and MSI2 double knockdown (DKD) to understand gene expression and functional changes upon MSI depletion. We characterized cancer stem cell characteristics, cell apoptosis and cell cycle progression via flow cytometry, mammospheres via spheroid assays, migration and proliferation via digital holographic microscopy, and cell viability using BrdU assays. Chemoresistance was determined for paclitaxel and cisplatin with MTT assays and radioresistance was assessed with clonogenic analyses. In parallel, we supported our in vitro data by analyzing publicly available patient IBC gene expression datasets. RESULTS: MSI1 and MSI2 are upregulated in breast cancer generally and IBC specifically. MSI2 is more commonly expressed compared to MSI1. MSI DKD attenuated proliferation, cell cycle progression, migration, and cell viability while increasing apoptosis. Stem cell characteristics CD44(+)/CD24(-), TERT and Oct4 were associated with MSI expression in vivo and were decreased in vitro after MSI DKD as was ALDH expression and mammosphere formation. In vivo, chemoresistant tumors were characterized by MSI upregulation upon chemotherapy application. In vitro, MSI DKD was able to alleviate chemo- and radioresistance. CONCLUSIONS: The Musashi RNA binding proteins are dysregulated in IBC and associated with tumor proliferation, cancer stem cell phenotype, chemo- and radioresistance. MSI downregulation alleviates therapy resistance and attenuates tumor proliferation in vitro.

Sox-2 positive cells identified in lymph nodes from endometriosis patients may play a role in the disease pathogenesis.

OBJECTIVE: This study aimed to characterize Sox-2 in sentinel lymph nodes and randomly obtained lymph nodes from endometriosis (EM) patients for the first time. STUDY DESIGN: This prospective study analyzed tissue samples from surgical specimens collected from May until December 2007 in the Endometriosis Center Charité, Berlin. Lymph node samples from 38 women aged between 22 and 49 years who underwent laparoscopy due to symptomatic EM were analyzed. The material was obtained either randomly or, in the case of deep infiltrating endometriosis, detected using 4 cc Patent Blue®, labeled intraoperatively, which made the sentinel lymph nodes available for histological examination. Together with hematoxylin and eosin staining, the sections were evaluated by immunohistochemistry with antibodies against estrogen and progesterone receptors and Sox-2. Using double-immunofluorescence microscopy, the colocalization of Sox-2 and estrogen receptors were evaluated. RESULTS: Sox-2-positive cells were identified in the lymph nodes' cortical and medullary zones, with a higher expression in the medullary layer. Occasionally, Sox-2 positive stained cell groups, called cell nests, could also be detected. The number of Sox-2 positive cells in the sentinel lymph nodes was almost three times higher than in the random lymph nodes (p = 0.031). A significant five-fold increase (p = 0.0013) in Sox-2 expression was seen in the estrogen and progesterone receptor (ER/PR) positive patient group compared to the progesterone receptor positive group or hormone receptor negative patients. Identical hormone-related Sox-2 expression was also detected separately for the sentinel lymph node group (p = 0.0174). Sox-2 showed pronounced colocalisation with estrogen receptors. CONCLUSION: The lymphatic involvement in EM is evidence of a systemic disease manifestation and provides evidence of an immune system failure. In recent years, many theories have been studied, but there is no single theory that could explain all aspects of EM. The future concept of EM is likely to incorporate the elements from all the pathogenetic theories already described. Through this study, stem cells and lymphatic metastasis theories were incorporated.

Role of Syndecans in Ovarian Cancer: New Diagnostic and Prognostic Biomarkers and Potential Therapeutic Targets.

Ovarian cancer (OC) is the eighth cancer both in prevalence and mortality in women and represents the deadliest female reproductive cancer. Due to generally vague symptoms, OC is frequently diagnosed only at a late and advanced stage, resulting in high mortality. The tumor extracellular matrix and cellular matrix receptors play a key role in the pathogenesis of tumor progression. Syndecans are a family of four transmembrane heparan sulfate proteoglycans (PG), including syndecan-1, -2, -3, and -4, which are dysregulated in a myriad of cancers, including OC. Many clinicopathological studies suggest that these proteins are promising diagnostic and prognostic biomarkers for OC. Furthermore, functions of the syndecan family in the regulation of cellular processes make it an interesting pharmacological target for anticancer therapies.

New Roles for Old Friends: Involvement of the Innate Immune System in Tumor Progression.

The association between the immune system and tumor progression has attracted much interest in the research community in recent years [...].

SPOCK1 Overexpression Suggests Poor Prognosis of Ovarian Cancer.

PURPOSE: Sparc/osteonectin, cwcv, and kazal-like domains proteoglycan 1 (SPOCK1) has been found in a variety of malignant tumors and is associated with a poor prognosis. We aimed to explore the role of SPOCK1 in ovarian cancer. METHODS: Ovarian cancer cell lines SKOV3 and SW626 were transfected with SPOCK1 overexpressing or empty vector using electroporation. Cells were studied by immunostaining and an automated Western blotting system. BrdU uptake and wound healing assays assessed cell proliferation and migration. SPOCK1 expression in human ovarian cancer tissues and in blood samples were studied by immunostaining and ELISA. Survival of patients with tumors exhibiting low and high SPOCK1 expression was analyzed using online tools. RESULTS: Both transfected cell lines synthesized different SPOCK1 variants; SKOV3 cells also secreted the proteoglycan. SPOCK1 overexpression stimulated DNA synthesis and cell migration involving p21CIP1. Ovarian cancer patients had increased SPOCK1 serum levels compared to healthy controls. Tumor cells of tissues also displayed abundant SPOCK1. Moreover, SPOCK1 levels were higher in untreated ovarian cancer serum and tissue samples and lower in recipients of chemotherapy. According to in silico analyses, high SPOCK1 expression was correlated with shorter survival. CONCLUSION: Our findings suggest SPOCK1 may be a viable anti-tumor therapeutic target and could be used for monitoring ovarian cancer.

Tumor suppressor miR-218 directly targets epidermal growth factor receptor (EGFR) expression in triple-negative breast cancer, sensitizing cells to irradiation.

PURPOSE: MicroRNA-218 (miR-218) is a key regulator of numerous processes relevant to tumor progression. In the present study, we aimed to characterize the relationship between miR-218 and the Epidermal Growth Factor Receptor (EGFR) as well as to understand downstream effects in triple-negative breast cancer (TNBC). METHODS: We assessed miR-218 and EGFR expression in cell lines and publicly available primary breast cancer gene expression data. We then overexpressed miR-218 in two TNBC cell lines and investigated effects on EGFR and downstream mitogen-activated protein (MAP) kinase signaling. Luciferase reporter assay was used to characterize a direct binding interaction between miR-218 and EGFR mRNA. Digital holographic microscopy helped investigate cell migration and dry mass after miR-218 overexpression. Cell division and invasion were assessed microscopically, while radiation response after miR-218 overexpression alone or combined with additional EGFR knockdown was investigated via clonogenic assays. RESULTS: We found an inverse correlation between EGFR expression and miR-218 levels in cell lines and primary breast cancer tissues. MiR-218 overexpression resulted in a downregulation of EGFR via direct binding of the mRNA. Activation of EGFR and downstream p44/42 MAPK signaling were reduced after pre-miR-218 transfection. Cell proliferation, motility and invasiveness were inhibited whereas cell death and mitotic catastrophe were upregulated in miR-218 overexpressing cells compared to controls. MiR-218 overexpressing and EGFR siRNA-treated cells were sensitized to irradiation, more than miR-218 overexpressing cells alone. CONCLUSION: This study characterizes the antagonistic relationship between miR-218 and EGFR. It also demonstrates downstream functional effects of miR-218 overexpression, leading to anti-tumorigenic cellular changes.

Neutrophil Extracellular Traps and Cancer: Trapping Our Attention with Their Involvement in Ovarian Cancer.

Neutrophils, the most abundant circulating leukocytes, play a well-known role in defense against pathogens through phagocytosis and degranulation. However, a new mechanism involving the release of neutrophil extracellular traps (NETs) composed of DNA, histones, calprotectin, myeloperoxidase, and elastase, among others, has been described. The so-called NETosis process can occur through three different mechanisms: suicidal, vital, and mitochondrial NETosis. Apart from their role in immune defense, neutrophils and NETs have been involved in physiopathological conditions, highlighting immunothrombosis and cancer. Notably, neutrophils can either promote or inhibit tumor growth in the tumor microenvironment depending on cytokine signaling and epigenetic modifications. Several neutrophils' pro-tumor strategies involving NETs have been documented, including pre-metastatic niche formation, increased survival, inhibition of the immune response, and resistance to oncologic therapies. In this review, we focus on ovarian cancer (OC), which remains the second most incidental but the most lethal gynecologic malignancy, partly due to the presence of metastasis, often omental, at diagnosis and the resistance to treatment. We deepen the state-of-the-art on the participation of NETs in OC metastasis establishment and progression and their involvement in resistance to chemo-, immuno-, and radiotherapies. Finally, we review the current literature on NETs in OC as diagnostic and/or prognostic markers, and their contribution to disease progression at early and advanced stages. The panoramic view provided in this article might pave the way for enhanced diagnostic and therapeutic strategies to improve the prognosis of cancer patients and, specifically, OC patients.

The Heparan Sulfate Proteoglycan Syndecan-1 Triggers Breast Cancer Cell-Induced Coagulability by Induced Expression of Tissue Factor.

Syndecan-1 (Sdc-1) upregulation is associated with poor prognosis in breast cancer. Sdc-1 knockdown results in reduced angiogenesis and the dysregulation of tissue factor (TF) pathway constituents. Here, we evaluate the regulatory mechanisms and functional consequences of the Sdc-1/TF-axis using Sdc-1 knockdown and overexpression approaches in MCF-7 and MDA-MB-231 breast cancer cells. Gene expression was analyzed by means of qPCR. Thrombin generation and cell migration were detected. Cell-cycle progression and apoptosis were investigated using flow cytometry. In MDA-MB-231 cells, IL6, IL8, VEGF, and IGFR-dependent signaling affected TF pathway expression depending on Sdc-1. Notably, Sdc-1 depletion and TF pathway inhibitor (TFPI) synergistically affected PTEN, MAPK, and STAT3 signaling. At the functional level, the antiproliferative and pro-apoptotic effects of TFPI depended on Sdc-1, whereas Sdc-1's modulation of cell motility was not affected by TFPI. Sdc-1 overexpression in MCF-7 and MDA-MB-231 cells led to increased TF expression, inducing a procoagulative phenotype, as indicated by the activation of human platelets and increased thrombin formation. A novel understanding of the functional interplay between Sdc-1 and the TF pathway may be compatible with the classical co-receptor role of Sdc-1 in cytokine signaling. This opens up the possibility of a new functional understanding, with Sdc-1 fostering coagulation and platelet communication as the key to the hematogenous metastatic spread of breast cancer cells.

The Tissue Factor Pathway in Cancer: Overview and Role of Heparan Sulfate Proteoglycans.

Historically, the only focus on tissue factor (TF) in clinical pathophysiology has been on its function as the initiation of the extrinsic coagulation cascade. This obsolete vessel-wall TF dogma is now being challenged by the findings that TF circulates throughout the body as a soluble form, a cell-associated protein, and a binding microparticle. Furthermore, it has been observed that TF is expressed by various cell types, including T-lymphocytes and platelets, and that certain pathological situations, such as chronic and acute inflammatory states, and cancer, may increase its expression and activity. Transmembrane G protein-coupled protease-activated receptors can be proteolytically cleaved by the TF:FVIIa complex that develops when TF binds to Factor VII (PARs). The TF:FVIIa complex can activate integrins, receptor tyrosine kinases (RTKs), and PARs in addition to PARs. Cancer cells use these signaling pathways to promote cell division, angiogenesis, metastasis, and the maintenance of cancer stem-like cells. Proteoglycans play a crucial role in the biochemical and mechanical properties of the cellular extracellular matrix, where they control cellular behavior via interacting with transmembrane receptors. For TFPI.fXa complexes, heparan sulfate proteoglycans (HSPGs) may serve as the primary receptor for uptake and degradation. The regulation of TF expression, TF signaling mechanisms, their pathogenic effects, and their therapeutic targeting in cancer are all covered in detail here.