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Alexander ET, Gilmour SK. Immunomodulatory role of thrombin in cancer progression. Mol Carcinog 2022; 61:527-536. [PMID: 35338515 DOI: 10.1002/mc.23398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 11/06/2022]
Abstract
Coagulation proteases and the generation of thrombin are increased in tumors. In addition, chemotherapeutic agents commonly used to treat malignant cancers can exacerbate cancer-associated thromboses. Thrombin can modify tumor cell behavior directly through the activation of protease-activated receptors (PAR) or indirectly by generating fibrin matrices. In addition to its role in generating fibrin to promote hemostasis, thrombin acts directly on multiple effector cells of the immune system impacting both acute and chronic inflammatory processes. Thrombin-mediated release of interleukin-6, tumor necrosis factor-α, and monocyte chemoattractant protein-1 leads to the accumulation of multiple tumor-infiltrating immunosuppressive cell populations including myeloid derived suppresser cells, M2-like macrophages, and T regulatory cells. Ablation of PAR-1 from the tumor microenvironment, but not the tumor, has been shown to dramatically reduce tumor growth and metastasis in multiple tumor models. Thrombin-activated platelets release immunosuppressive cytokines including transforming growth factor-β that can inhibit natural killer cell activity, helping tumor cells to evade host immunosurveillance. Taken together, there is strong evidence that thrombin influences cancer progression via multiple mechanisms, including the tumor immune response, with thrombin emerging as a target for novel therapeutic strategies for cancer.
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Affiliation(s)
- Eric T Alexander
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA
| | - Susan K Gilmour
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA
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Shavit-Stein E, Sheinberg E, Golderman V, Sharabi S, Wohl A, Gofrit SG, Zivli Z, Shelestovich N, Last D, Guez D, Daniels D, Gera O, Feingold K, Itsekson-Hayosh Z, Rosenberg N, Tamarin I, Dori A, Maggio N, Mardor Y, Chapman J, Harnof S. A Novel Compound Targeting Protease Receptor 1 Activators for the Treatment of Glioblastoma. Front Neurol 2018; 9:1087. [PMID: 30619047 PMCID: PMC6304418 DOI: 10.3389/fneur.2018.01087] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 11/28/2018] [Indexed: 01/27/2023] Open
Abstract
Data from human biopsies, in-vitro and in-vivo models, strongly supports the role of thrombin, and its protease-activated receptor (PAR1) in the pathology and progression of glioblastoma (GBM), a high-grade glial tumor. Activation of PAR1 by thrombin stimulates vasogenic edema, tumor adhesion and tumor growth. We here present a novel six amino acid chloromethyl-ketone compound (SIXAC) which specifically inhibits PAR1 proteolytic activation and counteracts the over-activation of PAR1 by tumor generated thrombin. SIXAC effects were demonstrated in-vitro utilizing 3 cell-lines, including the highly malignant CNS-1 cell-line which was also used as a model for GBM in-vivo. The in-vitro effects of SIXAC on proliferation rate, invasion and thrombin activity were measured by XTT, wound healing, colony formation and fluorescent assays, respectively. The effect of SIXAC on GBM in-vivo was assessed by measuring tumor and edema size as quantified by MRI imaging, by survival follow-up and brain histopathology. SIXAC was found in-vitro to inhibit thrombin-activity generated by CNS-1 cells (IC50 = 5 × 10-11M) and significantly decrease proliferation rate (p < 0.03) invasion (p = 0.02) and colony formation (p = 0.03) of these cells. In the CNS-1 GBM rat animal model SIXAC was found to reduce edema volume ratio (8.8 ± 1.9 vs. 4.9 ± 1, p < 0.04) and increase median survival (16 vs. 18.5 days, p < 0.02 by Log rank Mental-Cox test). These results strengthen the important role of thrombin/PAR1 pathway in glioblastoma progression and suggest SIXAC as a novel therapeutic tool for this fatal disease.
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Affiliation(s)
- Efrat Shavit-Stein
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Ehud Sheinberg
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
- Department of Neurosurgery, Rabin Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Valery Golderman
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Shirley Sharabi
- The Advanced Technology Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Anton Wohl
- Department of Neurosurgery, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Shany Guly Gofrit
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Zion Zivli
- Department of Neurosurgery, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | | | - David Last
- The Advanced Technology Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - David Guez
- The Advanced Technology Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Dianne Daniels
- The Advanced Technology Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Orna Gera
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Kate Feingold
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Zeev Itsekson-Hayosh
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Nurit Rosenberg
- Institute of Thrombosis and Heamostasis, Coagulation Laboratory, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Ilia Tamarin
- Institute of Thrombosis and Heamostasis, Coagulation Laboratory, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Amir Dori
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Nicola Maggio
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Yael Mardor
- The Advanced Technology Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Joab Chapman
- Department of Neurology and Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
- Robert and Martha Harden Chair in Mental and Neurological Diseases, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
| | - Sagi Harnof
- Department of Neurosurgery, Rabin Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Ramat Gan, Israel
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Ding JB, Chen JR, Xu HZ, Qin ZY. Effect of Hyperbaric Oxygen on the Growth of Intracranial Glioma in Rats. Chin Med J (Engl) 2016; 128:3197-203. [PMID: 26612296 PMCID: PMC4794883 DOI: 10.4103/0366-6999.170278] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background: Numerous studies have confirmed that hyperbaric oxygen (HBO) in combination with radiotherapy or chemotherapy may increase the efficacy of radiotherapy or chemotherapy in patients with glioma. However, whether HBO therapy alone may inhibit or promote the growth of malignant tumors remains controversial. This study aimed to investigate the effect of HBO on the growth of glioma in rats, and the impact of HBO on the expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1-alpha (HIF-1α), angiogenesis, and apoptosis of glioma cells. Methods: Male Sprague–Dawley rats were treated with or without HBO after glioma cell inoculation and followed for up to 16 days postinoculation. Rats were randomized to receive bilateral forelimb function tests (n = 20 per group) and head magnetic resonance imaging (n = 5 per group). Differences between HBO and control groups were tested using 2-sample independent t-tests and changes over time within treatment groups were analyzed using a repeated measurement analysis of variance with Bonferroni correction. The effect of HBO on the expression of VEGF, HIF-1α, von Willebrand factor, angiogenesis, and tumor cell apoptosis were also examined (n = 5 per group). Results: Forelimb function scores were reduced in both HBO-treated and control groups. HBO-treated rats had significantly larger tumor volume and more water in the cerebellum compared with control rats. The intratumoral expression of VEGF was significantly higher in HBO-treated rats compared with control rats (23.2% vs. 13.3%, P = 0.002). HIF-1α was significantly increased in HBO-treated rats compared with controls in the expression of both intratumoral (72.7% vs. 54.9%, P = 0.001) and peritumoral (2.6% vs. 1.9%, P = 0.003) cells. The intratumoral microvessel density (MVD) was significantly higher in the HBO group (15.6 vessels/field vs. 4.4 vessels/field, P < 0.001), and the peritumoral MVD was not significantly different between the two groups (P > 0.05). Apoptosis was significantly lower in HBO-treated rats compared with controls (44.4% vs. 82.8% for intratumoral; 10.1% vs. 77.5% for peritumoral, both P < 0.001). Conclusions: The current results demonstrate that HBO alone may promote tumor growth, and is therefore not suitable to treat patients with gliomas with neurological deficits or disorders with HBO alone. If HBO must be used as a mean of rehabilitation, it is recommended that HBO should be combined with radiotherapy or chemotherapy.
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Affiliation(s)
| | | | | | - Zhi-Yong Qin
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai 200040, China
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The Importance of Thrombin in Cerebral Injury and Disease. Int J Mol Sci 2016; 17:ijms17010084. [PMID: 26761005 PMCID: PMC4730327 DOI: 10.3390/ijms17010084] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 12/28/2015] [Accepted: 12/30/2015] [Indexed: 12/31/2022] Open
Abstract
There is increasing evidence that prothrombin and its active derivative thrombin are expressed locally in the central nervous system. So far, little is known about the physiological and pathophysiological functions exerted by thrombin in the human brain. Extra-hepatic prothrombin expression has been identified in neuronal cells and astrocytes via mRNA measurement. The actual amount of brain derived prothrombin is expected to be 1% or less compared to that in the liver. The role in brain injury depends upon its concentration, as higher amounts cause neuroinflammation and apoptosis, while lower concentrations might even be cytoprotective. Its involvement in numerous diseases like Alzheimer’s, multiple sclerosis, cerebral ischemia and haemorrhage is becoming increasingly clear. This review focuses on elucidation of the cerebral thrombin expression, local generation and its role in injury and disease of the central nervous system.
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Angiopoietin-1 Regulates Brain Endothelial Permeability through PTPN-2 Mediated Tyrosine Dephosphorylation of Occludin. PLoS One 2015; 10:e0130857. [PMID: 26090670 PMCID: PMC4474807 DOI: 10.1371/journal.pone.0130857] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 05/26/2015] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Blood brain barrier (BBB) breakdown and increased endothelial permeability is a hallmark of neuro-vascular inflammation. Angiopoietin-1 (Ang-1), a Tie-2 receptor agonist ligand, is known to modulate barrier function of endothelial cells; however the molecular mechanisms related to Ang-1 mediated repair of Tight Junctions (TJs) in brain endothelium still remain elusive. In this study, we investigated a novel role of non-receptor protein tyrosine phosphatase N-2 (PTPN-2) in Ang-1 mediated stabilization of tight junction proteins. METHOD AND RESULT To study the barrier protective mechanism of Ang-1, we challenged human brain microvascular endothelial cells in-vitro, with a potent inflammatory mediator thrombin. By using confocal microscopy and transwell permeability assay, we show that pretreatment of brain endothelial cells with Ang-1 diminish thrombin mediated disruption of TJs and increase in endothelial permeability. We also found that Ang-1 inhibits thrombin induced tyrosine phosphorylation of Occludin and promote Occludin interaction with Zona Occludens-1 (ZO-1) to stabilize TJs. Interestingly, our study revealed that depletion of PTPN-2 by siRNAs abolishes Ang-1 ability to promote tyrosine dephosphorylation of Occludin, resulting Occludin disassociation from ZO-1 and endothelial hyperpermeability. SUMMARY Collectively, our findings suggest that in brain endothelial cells blocking PTPN-2 mediated tyrosine phosphorylation of Occludin is a novel mechanism to maintain BBB function, and may offer a key therapeutic strategy for neuro-inflammatory disorders associated with BBB disruption.
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Sayyah J, Bartakova A, Nogal N, Quilliam LA, Stupack DG, Brown JH. The Ras-related protein, Rap1A, mediates thrombin-stimulated, integrin-dependent glioblastoma cell proliferation and tumor growth. J Biol Chem 2014; 289:17689-98. [PMID: 24790104 DOI: 10.1074/jbc.m113.536227] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Rap1 is a Ras family GTPase with a well documented role in ERK/MAP kinase signaling and integrin activation. Stimulation of the G-protein-coupled receptor PAR-1 with thrombin in human 1321N1 glioblastoma cells led to a robust increase in Rap1 activation. This response was sustained for up to 6 h and mediated through RhoA and phospholipase D (PLD). Thrombin treatment also induced a 5-fold increase in cell adhesion to fibronectin, which was blocked by down-regulating PLD or Rap1A or by treatment with a β1 integrin neutralizing antibody. In addition, thrombin treatment led to increases in phospho-focal adhesion kinase (tyrosine 397), ERK1/2 phosphorylation and cell proliferation, which were significantly inhibited in cells treated with β1 integrin antibody or Rap1A siRNA. To assess the role of Rap1A in tumor formation in vivo, we compared growth of 1321N1 cells stably expressing control, Rap1A or Rap1B shRNA in a mouse xenograft model. Deletion of Rap1A, but not of Rap1B, reduced tumor mass by >70% relative to control. Similar observations were made with U373MG glioblastoma cells in which Rap1A was down-regulated. Collectively, these findings implicate a Rap1A/β1 integrin pathway, activated downstream of G-protein-coupled receptor stimulation and RhoA, in glioblastoma cell proliferation. Moreover, our data demonstrate a critical role for Rap1A in glioblastoma tumor growth in vivo.
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Affiliation(s)
| | - Alena Bartakova
- Pathology, University of California at San Diego, La Jolla, California 92093 and
| | | | - Lawrence A Quilliam
- the Department of Biochemistry and Molecular Biology, Indiana University, Indianapolis, Indiana 46202
| | - Dwayne G Stupack
- Pathology, University of California at San Diego, La Jolla, California 92093 and
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Protease activated receptor-1 and brain edema formation in glioma models. ACTA NEUROCHIRURGICA. SUPPLEMENT 2013; 118:191-4. [PMID: 23564130 DOI: 10.1007/978-3-7091-1434-6_35] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
OBJECTIVE Our previous studies showed that thrombin contributes to brain edema in gliomas. The present study investigated the role of a thrombin receptor, protease activated receptor-1 (PAR-1), in edema formation in glioma models. METHODS These experiments were performed in Fischer 344 rats, PAR-1 knockout mice, and wild-type C57BL/6 mice controls. F98 glioma cells were infused into the right caudate. Animals were euthanized and the brains were used for measurements of brain edema and PAR-1 expression. RESULTS In rats, implantation of glioma cells resulted in significant brain edema in the ipsilateral hemisphere (82.6 ± ;1.4 vs. 78.1 ± 0.9 % in the contralateral hemisphere, p < 0.01). By Western blot analysis and RT-PCR, we found that both protein and mRNA levels of PAR-1 were upregulated in the glioma (p < 0.01). In mice, implantation of glioma cells also caused brain edema in the ipsilateral hemisphere (p < 0.05). Glioma-induced brain edema was less in PAR-1 knockout mice (day 12: 79.4 ;± 1.3 vs. 81.5 ± 1.1 % in the wild-type mice, p < ;0.05). CONCLUSION PAR-1 plays a role in glioma-induced brain edema. Clarification of the role of PAR-1 in edema formation should help to develop new therapeutic strategies for gliomas.
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Kirkman MA, Allan SM, Parry-Jones AR. Experimental intracerebral hemorrhage: avoiding pitfalls in translational research. J Cereb Blood Flow Metab 2011; 31:2135-51. [PMID: 21863040 PMCID: PMC3210340 DOI: 10.1038/jcbfm.2011.124] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 07/20/2011] [Accepted: 07/28/2011] [Indexed: 12/12/2022]
Abstract
Intracerebral hemorrhage (ICH) has the highest mortality of all stroke subtypes, yet treatments are mainly limited to supportive management, and surgery remains controversial. Despite significant advances in our understanding of ICH pathophysiology, we still lack preclinical models that accurately replicate the underlying mechanisms of injury. Current experimental ICH models (including autologous blood and collagenase injection) simulate different aspects of ICH-mediated injury but lack some features of the clinical condition. Newly developed models, notably hypertension- and oral anticoagulant therapy-associated ICH models, offer added benefits but further study is needed to fully validate them. Here, we describe and discuss current approaches to experimental ICH, with suggestions for changes in how this condition is studied in the laboratory. Although advances in imaging over the past few decades have allowed greater insight into clinical ICH, there remains an important role for experimental models in furthering our understanding of the basic pathophysiologic processes underlying ICH, provided limitations of animal models are borne in mind. Owing to differences in existing models and the failed translation of benefits in experimental ICH to clinical practice, putative neuroprotectants should be trialed in multiple models using both histological and functional outcomes until a more accurate model of ICH is developed.
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Affiliation(s)
- Matthew A Kirkman
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
| | - Stuart M Allan
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
| | - Adrian R Parry-Jones
- The University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Trust, Salford, UK
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Affiliation(s)
- Dae-Yul Kim
- Department of Rehabilitation Medicine, Asan Medical Center, University of Ulsan College Medicine, Korea
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Fisher SK, Cheema TA, Foster DJ, Heacock AM. Volume-dependent osmolyte efflux from neural tissues: regulation by G-protein-coupled receptors. J Neurochem 2008; 106:1998-2014. [PMID: 18518929 DOI: 10.1111/j.1471-4159.2008.05510.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The CNS is particularly vulnerable to reductions in plasma osmolarity, such as occur during hyponatremia, the most commonly encountered electrolyte disorder in clinical practice. In response to a lowered plasma osmolarity, neural cells initially swell but then are able to restore their original volume through the release of osmolytes, both inorganic and organic, and the exit of osmotically obligated water. Given the importance of the maintenance of cell volume within the CNS, mechanisms underlying the release of osmolytes assume major significance. In this context, we review recent evidence obtained from our laboratory and others that indicates that the activation of specific G-protein-coupled receptors can markedly enhance the volume-dependent release of osmolytes from neural cells. Of particular significance is the observation that receptor activation significantly lowers the osmotic threshold at which osmolyte release occurs, thereby facilitating the ability of the cells to respond to small, more physiologically relevant, reductions in osmolarity. The mechanisms underlying G-protein-coupled receptor-mediated osmolyte release and the possibility that this efflux can result in both physiologically beneficial and potentially harmful pathophysiological consequences are discussed.
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Affiliation(s)
- Stephen K Fisher
- Molecular and Behavioral Neuroscience Institute; and Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109-2200, USA.
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Tritschler F, Murín R, Birk B, Berger J, Rapp M, Hamprecht B, Verleysdonk S. Thrombin causes the enrichment of rat brain primary cultures with ependymal cells via protease-activated receptor 1. Neurochem Res 2007; 32:1028-35. [PMID: 17401674 DOI: 10.1007/s11064-006-9267-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Accepted: 12/20/2006] [Indexed: 11/25/2022]
Abstract
Ependymal cell culture models from rat have been developed over the last 20 years to facilitate biochemical studies on this least-studied glial cell type. The cell culture protocol calls for the presence of thrombin, which is essential for obtaining a high proportion of multiciliated ependymal cells. The serine protease appears to act via protease-activated receptor 1 to prevent the apoptosis of ependymal precursors and enhance their proliferation without affecting contaminating cells. Unciliated precursors differentiate into polyciliated ependymocytes by passing through a stage of monociliation. The message for protease-activated receptor (PAR) 1 is initially abundant in the cultures, but its level declines as the cells differentiate. Besides PAR 1, signalling through PAR 2 also promotes ciliation in rat brain primary cultures, albeit to a lesser degree than the thrombin receptor. Thrombin and other proteases may be involved in the regulation of ventricular wall development. This action would be mediated mainly by PAR1.
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Affiliation(s)
- Felix Tritschler
- Interfaculty Institute for Biochemistry, University of Tübingen, Tübingen, Germany
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Fernandes RS, Kirszberg C, Rumjanek VM, Monteiro RQ. On the molecular mechanisms for the highly procoagulant pattern of C6 glioma cells. J Thromb Haemost 2006; 4:1546-52. [PMID: 16839352 DOI: 10.1111/j.1538-7836.2006.01985.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND That there is a correlation between cancer and procoagulant states is well-known. C6 glioma cell line was originally induced in random-bred Wistar-Furth rats and is morphologically similar to glioblastoma multiforme, the most common aggressive glioma resistant to therapeutic interventions. OBJECTIVES In this study we analyzed the molecular mechanisms responsible for the highly procoagulant properties of C6 glioma cells. METHODS The presence of tissue factor (TF) and phosphatidylserine (PS) in C6 cells was investigated by flow-cytometric and functional analyses. The assembly of extrinsic tenase, intrinsic tenase and prothrombinase complexes on these cells was studied using enzymatic assays employing plasma or purified proteins. RESULTS TF was identified by flow-cytometric and functional [factor (F) Xa formation in the presence of cells and FVIIa] assays. Alternatively, conversion of FX into FXa was also observed in the presence of C6 cells, FIXa and FVIIIa. This effect was both cell- and FVIIIa-dependent, being consistent with formation of the intrinsic tenase complex. C6 cells were also able to activate prothrombin in the presence of FXa and FVa, thus supporting formation of the prothrombinase complex. This ability was similar to positive controls performed with PS-containing vesicles. Accordingly, exposure of PS on C6 cells was demonstrated by flow cytometry employing specific anti-PS antibodies. In addition, annexin V, which blocks PS binding sites, inhibited FX and prothrombin conversion by their respective C6-assembled activating complexes. CONCLUSION C6 glioma cells support all procoagulant reactions leading to robust thrombin formation. This ability results from concomitant TF exposure and from the presence of the anionic lipid PS at the outer leaflet of cell membrane. Therefore, this animal cell line may be used to explore new aspects concerning the role of blood coagulation proteins in tumor biology, especially those affecting the central nervous system.
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Affiliation(s)
- R S Fernandes
- Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Bauhínia 400, Cidade Universitária, Ilha do Fundão, Rio de Janeiro 21941-590, Brazil
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