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Aleksandrowicz K, Hempel D, Polityńska B, Wojtukiewicz AM, Honn KV, Tang DG, Wojtukiewicz MZ. The Complex Role of Thrombin in Cancer and Metastasis: Focus on Interactions with the Immune System. Semin Thromb Hemost 2024; 50:462-473. [PMID: 37984359 DOI: 10.1055/s-0043-1776875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Thrombin, a pleiotropic enzyme involved in coagulation, plays a crucial role in both procoagulant and anticoagulant pathways. Thrombin converts fibrinogen into fibrin, initiates platelet activation, and promotes clot formation. Thrombin also activates anticoagulant pathways, indirectly inhibiting factors involved in coagulation. Tissue factor triggers thrombin generation, and the overexpression of thrombin in various cancers suggests that it is involved in tumor growth, angiogenesis, and metastasis. Increased thrombin generation has been observed in cancer patients, especially those with metastases. Thrombin exerts its effects through protease-activated receptors (PARs), particularly PAR-1 and PAR-2, which are involved in cancer progression, angiogenesis, and immunological responses. Thrombin-mediated signaling promotes angiogenesis by activating endothelial cells and platelets, thereby releasing proangiogenic factors. These functions of thrombin are well recognized and have been widely described. However, in recent years, intriguing new findings concerning the association between thrombin activity and cancer development have come to light, which justifies a review of this research. In particular, there is evidence that thrombin-mediated events interact with the immune system, and may regulate its response to tumor growth. It is also worth reevaluating the impact of thrombin on thrombocytes in conjunction with its multifaceted influence on tumor progression. Understanding the role of thrombin/PAR-mediated signaling in cancer and immunological responses is crucial, particularly in the context of developing immunotherapies. In this systematic review, we focus on the impact of the thrombin-related immune system response on cancer progression.
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Affiliation(s)
- Karolina Aleksandrowicz
- Department of Clinical Oncology, Medical University, Białystok, Poland
- Comprehensive Cancer Center, Bialystok, Poland
| | - Dominika Hempel
- Department of Clinical Oncology, Medical University, Białystok, Poland
- Comprehensive Cancer Center, Bialystok, Poland
| | - Barbara Polityńska
- Department of Psychology and Philosophy, Medical University of Białystok, Białystok, Poland
| | - Anna M Wojtukiewicz
- Department of Psychology and Philosophy, Medical University of Białystok, Białystok, Poland
| | - Kenneth V Honn
- Department of Pathology-School of Medicine, Bioactive Lipids Research Program, Detroit, Michigan
- Department of Chemistry, Wayne State University, Detroit, Michigan
- Department of Oncology, Wayne State University, Detroit, Michigan
| | - Dean G Tang
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Marek Z Wojtukiewicz
- Department of Clinical Oncology, Medical University, Białystok, Poland
- Comprehensive Cancer Center, Bialystok, Poland
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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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3
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Molecular targeting of breast and colon cancer cells by PAR1 mediated apoptosis through a novel pro-apoptotic peptide. Apoptosis 2018; 23:679-694. [DOI: 10.1007/s10495-018-1485-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Ray T, Pal A. PAR-1 mediated apoptosis of breast cancer cells by V. cholerae hemagglutinin protease. Apoptosis 2016; 21:609-20. [PMID: 26897170 DOI: 10.1007/s10495-016-1229-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Bacterial toxins have emerged as promising agents in cancer treatment strategy. Hemagglutinin (HAP) protease secreted by Vibrio cholerae induced apoptosis in breast cancer cells and regresses tumor growth in mice model. The success of novel cancer therapies depends on their selectivity for cancer cells with limited toxicity for normal tissues. Increased expression of Protease Activated Receptor-1 (PAR-1) has been reported in different malignant cells. In this study we report that HAP induced activation and over expression of PAR-1 in breast cancer cells (EAC). Immunoprecipitation studies have shown that HAP specifically binds with PAR-1. HAP mediated activation of PAR-1 caused nuclear translocation of p50-p65 and the phosphorylation of p38 which triggered the activation of NFκB and MAP kinase signaling pathways. These signaling pathways enhanced the cellular ROS level in malignant cells that induced the intrinsic pathway of cell apoptosis. PAR-1 mediated apoptosis by HAP of malignant breast cells without effecting normal healthy cells in the same environment makes it a good therapeutic agent for treatment of cancer.
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Affiliation(s)
- Tanusree Ray
- Division of Pathophysiology, National Institute of Cholera and Enteric Diseases, P-33, CIT Road, Scheme-XM, Beliaghata, Kolkata, 700010, India
| | - Amit Pal
- Division of Pathophysiology, National Institute of Cholera and Enteric Diseases, P-33, CIT Road, Scheme-XM, Beliaghata, Kolkata, 700010, India.
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Zigler M, Kamiya T, Brantley EC, Villares GJ, Bar-Eli M. PAR-1 and thrombin: the ties that bind the microenvironment to melanoma metastasis. Cancer Res 2011; 71:6561-6. [PMID: 22009534 PMCID: PMC3206157 DOI: 10.1158/0008-5472.can-11-1432] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Progression of melanoma is dependent on cross-talk between tumor cells and the adjacent microenvironment. The thrombin receptor, protease-activated receptor-1 (PAR-1), plays a key role in exerting this function during melanoma progression. PAR-1 and its activating factors, which are expressed on tumor cells and the surrounding stroma, induce not only coagulation but also cell signaling, which promotes the metastatic phenotype. Several adhesion molecules, cytokines, growth factors, and proteases have recently been identified as downstream targets of PAR-1 and have been shown to modulate interactions between tumor cells and the microenvironment in the process of melanoma growth and metastasis. Inhibiting such interactions by targeting PAR-1 could potentially be a useful therapeutic modality for melanoma patients.
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Affiliation(s)
- Maya Zigler
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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Functional role of kallikrein 6 in regulating immune cell survival. PLoS One 2011; 6:e18376. [PMID: 21464892 PMCID: PMC3065477 DOI: 10.1371/journal.pone.0018376] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 03/04/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Kallikrein 6 (KLK6) is a newly identified member of the kallikrein family of secreted serine proteases that prior studies indicate is elevated at sites of central nervous system (CNS) inflammation and which shows regulated expression with T cell activation. Notably, KLK6 is also elevated in the serum of multiple sclerosis (MS) patients however its potential roles in immune function are unknown. Herein we specifically examine whether KLK6 alters immune cell survival and the possible mechanism by which this may occur. METHODOLOGY/PRINCIPAL FINDINGS Using murine whole splenocyte preparations and the human Jurkat T cell line we demonstrate that KLK6 robustly supports cell survival across a range of cell death paradigms. Recombinant KLK6 was shown to significantly reduce cell death under resting conditions and in response to camptothecin, dexamethasone, staurosporine and Fas-ligand. Moreover, KLK6-over expression in Jurkat T cells was shown to generate parallel pro-survival effects. In mixed splenocyte populations the vigorous immune cell survival promoting effects of KLK6 were shown to include both T and B lymphocytes, to occur with as little as 5 minutes of treatment, and to involve up regulation of the pro-survival protein B-cell lymphoma-extra large (Bcl-XL), and inhibition of the pro-apoptotic protein Bcl-2-interacting mediator of cell death (Bim). The ability of KLK6 to promote survival of splenic T cells was also shown to be absent in cell preparations derived from PAR1 deficient mice. CONCLUSION/SIGNIFICANCE KLK6 promotes lymphocyte survival by a mechanism that depends in part on activation of PAR1. These findings point to a novel molecular mechanism regulating lymphocyte survival that is likely to have relevance to a range of immunological responses that depend on apoptosis for immune clearance and maintenance of homeostasis.
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Role of protease-activated receptor-2 on cell death and DNA fragmentation in Helicobacter pylori-infected gastric epithelial cells. J Transl Med 2010; 8:85. [PMID: 20846373 PMCID: PMC2945981 DOI: 10.1186/1479-5876-8-85] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 09/16/2010] [Indexed: 12/16/2022] Open
Abstract
Background Helicobacter pylori (H. pylori) infection is associated with chronic gastritis, peptic ulceration and gastric carcinoma. Protease-activated receptor-2 (PAR-2), which is activated by trypsin, induced the activation of mitogen-activated protein kinases (MAPK), cell proliferation and apoptosis in several cells. Previously, we found that H. pylori induces the expression of PAR-2, which mediates the expression of adhesion molecules integrins in gastric epithelial cells. In the present study, the role of PAR-2 on H. pylori-induced cell death was investigated by determining cell viability, DNA fragmentation, and the activation of MAPK in gastric epithelial AGS cells. Methods AGS cells were cultured in the presence of H. pylori transfected with PAR-2 antisense (AS) oligonucleotide (ODN) or treated with a soybean trypsin inhibitor (SBTI). Viable cells and DNA fragmentation were determined by trypan blue exclusion assay and the amount of oligonucleosome-bound DNA, respectively. The activation of MAPK such as extracellular signal-regulated kinases (ERK), p38, and c-Jun N-terminal kinases (JNK), was assessed by Western blotting for phospho-specific forms of MAPK. Results H. pylori-induced cell death and DNA fragmentation augmented in the cells transfected with PAR-2 AS ODN or treated with SBTI. The activation of MAPK, induced by H. pylori, were suppressed by transfection with PAR-2 AS ODN or treatment with SBTI. Conclusion PAR-2, whose expression is induced by H. pylori, may prevent cell death and DNA fragmentation with the activation of MAPK in gastric epithelial cells.
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Katsarou K, Lavdas AΑ, Tsitoura P, Serti E, Markoulatos P, Mavromara P, Georgopoulou U. Endocytosis of hepatitis C virus non-enveloped capsid-like particles induces MAPK-ERK1/2 signaling events. Cell Mol Life Sci 2010; 67:2491-506. [PMID: 20358251 PMCID: PMC11115770 DOI: 10.1007/s00018-010-0351-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 03/08/2010] [Accepted: 03/11/2010] [Indexed: 12/12/2022]
Abstract
Although HCV is an enveloped virus, naked nucleocapsids have been reported in the serum of infected patients. The HCV core particle serves as a protective capsid shell for the viral genome and recombinant in vitro assembled HCV core particles induce strong specific immunity. We investigated the post-binding mechanism of recombinant core particle uptake and its intracellular fate. In hepatic cells, these particles are internalized, most likely in a clathrin-dependent pathway, reaching early to late endosomes and finally lysosomes. The endocytic acidic milieu is implicated in trafficking process. Using specific phosphoantibodies, signaling pathway inhibitors and chemical agents, ERK(1/2) was found to be activated in a sustained way after endocytosis, followed by downstream immediate early genes (c-fos and egr-1) modulation. We propose that the intriguing properties of cellular internalization of HCV non-enveloped particles can induce specific ERK(1/2)-MAPKs events that could be important in HCV life cycle and pathogenesis of HCV infection.
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Affiliation(s)
| | - Alexandros Α. Lavdas
- Laboratory of Cellular and Molecular Neurobiology, Hellenic Pasteur Institute, Athens, Greece
| | - Panagiota Tsitoura
- Present Address: Insect Molecular Genetics and Biotechnology, Institute of Biology, NCSR Demokritos, Athens, Greece
| | - Elisavet Serti
- Molecular Virology Laboratory, Hellenic Pasteur Institute, Athens, Greece
| | | | - Penelope Mavromara
- Molecular Virology Laboratory, Hellenic Pasteur Institute, Athens, Greece
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Thippegowda PB, Singh V, Sundivakkam PC, Xue J, Malik AB, Tiruppathi C. Ca2+ influx via TRPC channels induces NF-kappaB-dependent A20 expression to prevent thrombin-induced apoptosis in endothelial cells. Am J Physiol Cell Physiol 2009; 298:C656-64. [PMID: 20032510 DOI: 10.1152/ajpcell.00456.2009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
NF-kappaB signaling is known to induce the expression of antiapoptotic and proinflammatory genes in endothelial cells (ECs). We have shown recently that Ca(2+) influx through canonical transient receptor potential (TRPC) channels activates NF-kappaB in ECs. Here we show that Ca(2+) influx signal prevents thrombin-induced apoptosis by inducing NF-kappaB-dependent A20 expression in ECs. Knockdown of TRPC1 expressed in human umbilical vein ECs with small interfering RNA (siRNA) suppressed thrombin-induced Ca(2+) influx and NF-kappaB activation in ECs. Interestingly, we observed that thrombin induced >25% of cell death (apoptosis) in TRPC1-knockdown ECs whereas thrombin had no effect on control or control siRNA-transfected ECs. To understand the basis of EC survival, we performed gene microarray analysis using ECs. Thrombin stimulation increased only a set of NF-kappaB-regulated genes 3- to 14-fold over basal levels in ECs. Expression of the antiapoptotic gene A20 was the highest among these upregulated genes. Like TRPC1 knockdown, thrombin induced apoptosis in A20-knockdown ECs. To address the importance of Ca(2+) influx signal, we measured thrombin-induced A20 expression in control and TRPC1-knockdown ECs. Thrombin-induced p65/RelA binding to A20 promoter-specific NF-kappaB sequence and A20 protein expression were suppressed in TRPC1-knockdown ECs compared with control ECs. Furthermore, in TRPC1-knockdown ECs, thrombin induced the expression of proapoptotic proteins caspase-3 and BAX. Importantly, thrombin-induced apoptosis in TRPC1-knockdown ECs was prevented by adenovirus-mediated expression of A20. These results suggest that Ca(2+) influx via TRPC channels plays a critical role in the mechanism of cell survival signaling through A20 expression in ECs.
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Affiliation(s)
- Prabhakar B Thippegowda
- Dept. of Pharmacology, College of Medicine, Univ. of Illinois, 835 South Wolcott Ave., Chicago, IL 60612, USA
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Quan L, Jian Z, Ping Z, Weiming L. Proteinase-activated receptor-1 mediates allogeneic CD8(+) T cell-induced apoptosis of vascular endothelial cells. Med Oncol 2009; 26:379-85. [PMID: 19082770 DOI: 10.1007/s12032-008-9132-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2008] [Accepted: 11/05/2008] [Indexed: 10/21/2022]
Abstract
Vascular endothelial-cells injury plays a pivotal role in the pathogenesis of graft-versus-host disease (GVHD) and transplant-associated endothelial injury syndrome. Vascular endothelial cells are an exposed target tissue for immune-mediated injury during GVHD. Early endothelial injury syndromes share common features with acute GVHD. Chronic GVHD leads to a rarefaction of microvessels caused by the infiltration of alloreactive cytotoxic T lymphocytes. In this context, allogeneic reactive cytotoxic T cell may contribute to apoptosis of vascular endothelial cells. The involvement of proteinase-activated receptor (PAR-1) in regulation of apoptosis has been recently recognized in many cell types. We hypothesized that apoptosis of vascular endothelial cells induced by allogeneic cytotoxic T cell are mediated via the PAR-1. Allogeneic CD8(+) T cell, PAR-1 agonist peptide (SFLLRN) induced apoptosis of human umbilical vein endothelial cells (HUVECs) and human dermal microvascular endothelial cells (HDMECs) as assessed by AnnexinV-FITC labeling. To ascertain the mechanism of endothelial apoptosis, we determined that allogeneic CD8(+) T cell, SFLLRN enhanced cleavage of caspase-3 and led to p38MAPK activation as assessed by Western blot. The effects of allogeneic CD8(+) T cell and SFLLRN on apoptosis of vascular endothelial cells were largely prevented by a cleavage-blocking anti-human PAR-1-antibody (ATAP2) and a specific inhibitor of p38MAPK. In concert, these observations provide strong evidence that allogeneic CD8(+) T cell induces apoptosis of human vascular endothelial cells through PAR-1-dependent modulation of intrinsic apoptotic pathway via alterations of p38MAPK and caspase-3.
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Affiliation(s)
- Li Quan
- Institute of Hematology, Tong ji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
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11
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Abstract
The regulation of survival and cell death is a key determinant of cell fate. Recent evidence shows that survival and death machineries are regulated along the cell cycle. In the present paper, we show that BimEL [a BH3 (Bcl-2 homology 3)-only member of the Bcl-2 family of proteins; Bim is Bcl-2-interacting mediator of cell death; EL is the extra-long form] is phosphorylated in mitosis. This post-translational modification is dependent on MEK (mitogen-activated protein kinase/extracellular-signal-regulated kinase kinase) and growth factor signalling. Interestingly, FGF (fibroblast growth factor) signalling seems to play an essential role in this process, since, in the presence of serum, inhibition of FGF receptors abrogated phosphorylation of Bim in mitosis. Moreover, we have shown bFGF (basic FGF) to be sufficient to induce phosphorylation of Bim in serum-free conditions in any phase of the cell cycle, and also to significantly rescue cells from serum-deprivation-induced apoptosis. Our results show that, in mitosis, Bim is phosphorylated downstream of growth factor signalling in a MEK-dependent manner, with FGF signalling playing an important role. We suggest that phosphorylation of Bim is a decisive step for the survival of proliferating cells.
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Affiliation(s)
- Mário Grãos
- Centro Biologia Desenvolvimento, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Alexandra D. Almeida
- Centro Biologia Desenvolvimento, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Sukalyan Chatterjee
- Centro Biologia Desenvolvimento, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
- To whom correspondence should be addressed (email )
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Naldini A, Filippi I, Ardinghi C, Silini A, Giavazzi R, Carraro F. Identification of a functional role for the protease-activated receptor-1 in hypoxic breast cancer cells. Eur J Cancer 2008; 45:454-60. [PMID: 19046876 DOI: 10.1016/j.ejca.2008.10.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 10/10/2008] [Accepted: 10/16/2008] [Indexed: 11/30/2022]
Abstract
Aberrant expression of the protease-activated receptor (PAR)-1 has been associated with tumour progression. Indeed, PAR-1 expression correlates with tumour invasiveness, as well as with cancer cell survival. As the tumour microenvironment is characterised by a low oxygen tension, we decided to investigate the role of PAR-1 in cancer cells exposed to a hypoxic microenvironment. In this study we show that hypoxia enhances PAR-1 expression in MDAMB231 breast cancer cells. We next provided evidence for a novel role of PAR-1 in protecting hypoxic breast cancer against cell death, since inhibition of PAR-1 by RNA interference resulted in a decreased cell survival. Finally, we found that treatment of hypoxic MDAMB231 cells with the specific PAR-1 agonist peptide (TRAP) resulted in a significant increase of cell survival and migration. The overall results identify for the first time a functional role for PAR-1 in the cellular responses of breast cancer to a hypoxic microenvironment.
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Affiliation(s)
- Antonella Naldini
- Department of Physiology, University of Siena, Via Aldo Moro, 53100 Siena, Italy.
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Frederix K, Kooter IM, van Oerle R, Fens D, Hamulyak K, Gerlofs-Nijland ME, Ten Cate H, Spronk HM. A new method to determine tissue specific tissue factor thrombomodulin activities: endotoxin and particulate air pollution induced disbalance. Thromb J 2008; 6:14. [PMID: 18828903 PMCID: PMC2569913 DOI: 10.1186/1477-9560-6-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2008] [Accepted: 10/01/2008] [Indexed: 11/18/2022] Open
Abstract
Background Increase in tissue factor (TF) and loss in thrombomodulin (TM) antigen levels has been described in various inflammatory disorders. The functional consequences of such changes in antigen concentrations in the coagulation balance are, however, not known. This study was designed to assess the consequences of inflammation-driven organ specific functional properties of the procoagulant response. Methods Tissue specific procoagulant activity was assessed by adding tissue homogenate to normal human pool plasma and recording of the thrombin generation curve. The new technique was subsequently applied on two inflammation driven animal models: 1) mouse lipopolysaccharide (LPS) induced endotoxemia and 2) spontaneously hypertensive rats exposed to environmental air pollution (particulate matter (PM). Results Addition of lung tissue from untreated animals to human plasma suppressed the endogenous thrombin potential (ETP) (175 ± 61 vs. 1437 ± 112 nM.min for control). This inhibitory effect was due to TM, because a) it was absent in protein C deficient plasma and b) lungs from TMpro/pro mice allowed full thrombin generation (ETP: 1686 ± 209 nM.min). The inhibitory effect of TM was lost after LPS administration to mice, which induced TF activity in lungs of C57Bl/6 mice as well as increased the ETP (941 ± 523 vs. 194 ± 159 nM.min for control). Another pro-inflammatory stimulus, PM dose-dependently increased TF in the lungs of spontaneously hypertensive rats at 4 and 48 hours after PM exposure. The ETP increased up to 48 hours at the highest concentration of PM (1441 ± 289 nM.min vs. saline: 164 ± 64 nM.min, p < 0.0001), suggesting a concentration- and time dependent reduction in TM activity. Conclusion Inflammation associated procoagulant effects in tissues are dependent on variations in activity of the TF-TM balance. The application of these novel organ specific functional assays is a useful tool to monitor inflammation-driven shifts in the coagulation balance within animal or human tissues.
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Affiliation(s)
- Kim Frederix
- Department of Internal Medicine, Laboratory for Clinical Thrombosis and Haemostasis, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands.
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Duarte M, Kolev V, Kacer D, Mouta-Bellum C, Soldi R, Graziani I, Kirov A, Friesel R, Liaw L, Small D, Verdi J, Maciag T, Prudovsky I. Novel cross-talk between three cardiovascular regulators: thrombin cleavage fragment of Jagged1 induces fibroblast growth factor 1 expression and release. Mol Biol Cell 2008; 19:4863-74. [PMID: 18784255 DOI: 10.1091/mbc.e07-12-1237] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Angiogenesis is controlled by several regulatory mechanisms, including the Notch and fibroblast growth factor (FGF) signaling pathways. FGF1, a prototype member of FGF family, lacks a signal peptide and is released through an endoplasmic reticulum-Golgi-independent mechanism. A soluble extracellular domain of the Notch ligand Jagged1 (sJ1) inhibits Notch signaling and induces FGF1 release. Thrombin, a key protease of the blood coagulation cascade and a potent inducer of angiogenesis, stimulates rapid FGF1 release through a mechanism dependent on the major thrombin receptor protease-activated receptor (PAR) 1. This study demonstrates that thrombin cleaves Jagged1 in its extracellular domain. The sJ1 form produced as a result of thrombin cleavage inhibits Notch-mediated CBF1/Suppressor of Hairless [(Su(H)]/Lag-1-dependent transcription and induces FGF1 expression and release. The overexpression of Jagged1 in PAR1 null cells results in a rapid thrombin-induced export of FGF1. These data demonstrate the existence of novel cross-talk between thrombin, FGF, and Notch signaling pathways, which play important roles in vascular formation and remodeling.
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Affiliation(s)
- Maria Duarte
- Center for Molecular Medicine, Maine Medical Center Research Institute, Scarborough, ME 04074, USA
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Gorbacheva LR, Storozhevykh TP, Pinelis VG, Davydova ON, Ishiwata S, Strukova SM. Activated protein C via PAR1 receptor regulates survival of neurons under conditions of glutamate excitotoxicity. BIOCHEMISTRY. BIOKHIMIIA 2008; 73:717-24. [PMID: 18620539 DOI: 10.1134/s0006297908060138] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The effect of an anticoagulant and cytoprotector blood serine proteinase--activated protein C (APC)--on survival of cultured hippocampal and cortical neurons under conditions of glutamate-induced excitotoxicity has been studied. Low concentrations of APC (0.01-10 nM) did not cause neuron death, but in the narrow range of low concentrations APC twofold and stronger decreased cell death caused by glutamate toxicity. High concentrations of APC (>50 nM) induced the death of hippocampal neurons similarly to the toxic action of glutamate. The neuroprotective effect of APC on the neurons was mediated by type 1 proteinase-activated receptor (PAR1), because the inactivation of the enzyme with phenylmethylsulfonyl fluoride or PAR1 blockade by a PAR1 peptide antagonist ((Tyr1)-TRAP-7) prevented the protective effect of APC. Moreover, APC inhibited the proapoptotic effect of 10 nM thrombin on the neurons. Geldanamycin, a specific inhibitor of heat shock protein Hsp90, completely abolished the antiapoptotic effect of 0.1 nM APC on glutamate-induced cytotoxicity in the hippocampal neurons. Thus, APC at low concentrations, activating PAR1, prevents the death of hippocampal and cortical neurons under conditions of glutamate excitotoxicity.
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Affiliation(s)
- L R Gorbacheva
- Biology Faculty, Lomonosov Moscow State University, Moscow, 119899, Russia
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Arkell RS, Dickinson RJ, Squires M, Hayat S, Keyse SM, Cook SJ. DUSP6/MKP-3 inactivates ERK1/2 but fails to bind and inactivate ERK5. Cell Signal 2008; 20:836-43. [DOI: 10.1016/j.cellsig.2007.12.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Accepted: 12/17/2007] [Indexed: 10/22/2022]
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Cuomo O, Pignataro G, Gala R, Scorziello A, Gravino E, Piazza O, Tufano R, Di Renzo G, Annunziato L. Antithrombin reduces ischemic volume, ameliorates neurologic deficits, and prolongs animal survival in both transient and permanent focal ischemia. Stroke 2007; 38:3272-9. [PMID: 17975103 DOI: 10.1161/strokeaha.107.488486] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Antithrombin (AT), a glycoprotein belonging to the serpin family, blocks thrombin formation and activity at several steps. Thrombin, beside its relevant role in the coagulation cascade, exerts neurodetrimental effects through the activation of a family of protease-activated receptors, which can be implicated in stroke pathophysiology. The aims of the present study were to evaluate whether AT could reduce brain damage, ameliorate neurologic deficits, and prolong animal survival. METHODS Two different doses of AT (10 and 30 IU/kg IP) were administered 3 hours, 6 hours, or 3 and 6 hours after an ischemic insult to mice and rats subjected to either transient or permanent focal ischemia. Ischemic volume was evaluated 24 hours or 7 days after the ischemic insult. Neurologic deficits were also scored. RESULTS In mice, 10 or 30 IU/kg AT administered twice, at 3 and 6 hours after transient ischemia, and 30 IU/kg AT administered 3 hours only after transient ischemia substantially reduced total ischemic volume, significantly improved neurologic deficits evaluated 24 hours after the insult, and prolonged animal survival. In rats, the same doses given at the same time intervals significantly reduced ischemic volume, evaluated 24 hours after permanent ischemia. CONCLUSIONS These results indicate that AT remarkably reduces infarct volume, ameliorates neurologic deficit scores, and prolongs animal survival in 2 rodent models of brain ischemia. Taken together, our data suggest that AT, delivered via systemic administration, an easily achievable route of administration and in a clinically useful time window, could represent a new therapeutic strategy to be validated for the clinical treatment of human stroke.
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Affiliation(s)
- Ornella Cuomo
- Division of Pharmacology, Department of Neuroscience, School of Medicine, Federico II, University of Naples, Via S Pansini 5, 80131 Naples, Italy
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18
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Kawao N, Okada K, Kawata S, Okamoto C, Tsuritani M, Ueshima S, Matsuo O. Plasmin decreases the BH3-only protein BimEL via the ERK1/2 signaling pathway in hepatocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2007; 1773:718-27. [PMID: 17482686 DOI: 10.1016/j.bbamcr.2007.03.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2006] [Revised: 03/08/2007] [Accepted: 03/14/2007] [Indexed: 10/23/2022]
Abstract
Since the signal transduction mechanisms responsible for liver regeneration mediated by the plasminogen/plasmin system remain largely undetermined, we have investigated whether plasmin regulates the pro-apoptotic protein Bim(EL) in primary hepatocytes. Plasmin bound to hepatocytes in part via its lysine binding sites (LBS). Plasmin also triggered phosphorylation of ERK1/2 without cell detachment. The plasmin-induced phosphorylation of ERK1/2 was inhibited by the LBS inhibitor epsilon-aminocaproic acid (EACA), the serine protease inhibitor aprotinin, and the MEK inhibitor PD98059. DFP-inactivated plasmin failed to phosphorylate ERK1/2. Plasmin temporally decreased the starvation-induced expression of Bim(EL) and activation of caspase-3 via the ERK1/2 signaling pathway, resulting in an enhancement of cell survival. The amount of mRNA for Bim increased 1 day after the injection of CCl(4) in livers of plasminogen knockout (Plg-KO) and the wild-type (WT) mice. The increase in Bim(EL) protein persisted for at least 7 days post-injection in livers of Plg-KO mice, whereas WT mice showed an increase in Bim(EL) protein 1 day after the injection. Plg-KO and WT mice showed notable phosphorylation of ERK1/2 7 and 3 days after the injection of CCl(4), respectively. Our data suggest that the plasminogen/plasmin system could decrease Bim(EL) expression via the ERK1/2 signaling pathway during liver regeneration.
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Affiliation(s)
- Naoyuki Kawao
- Department of Physiology, School of Medicine, Kinki University, 377-2, Ohnohigashi, Osakasayama, 589-8511, Japan
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19
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Ewings KE, Hadfield-Moorhouse K, Wiggins CM, Wickenden JA, Balmanno K, Gilley R, Degenhardt K, White E, Cook SJ. ERK1/2-dependent phosphorylation of BimEL promotes its rapid dissociation from Mcl-1 and Bcl-xL. EMBO J 2007; 26:2856-67. [PMID: 17525735 PMCID: PMC1894764 DOI: 10.1038/sj.emboj.7601723] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Accepted: 04/20/2007] [Indexed: 12/14/2022] Open
Abstract
The proapoptotic protein Bim is expressed de novo following withdrawal of serum survival factors. Here, we show that Bim-/- fibroblasts and epithelial cells exhibit reduced cell death following serum withdrawal in comparison with their wild-type counterparts. In viable cells, Bax associates with Bcl-2, Bcl-x(L) and Mcl-1. Upon serum withdrawal, newly expressed Bim(EL) associates with Bcl-x(L) and Mcl-1, coinciding with the dissociation of Bax from these proteins. Survival factors can prevent association of Bim with pro-survival proteins by preventing Bim expression. However, we now show that even preformed Bim(EL)/Mcl-1 and Bim(EL)/Bcl-x(L) complexes can be rapidly dissociated following activation of ERK1/2 by survival factors. The dissociation of Bim from Mcl-1 is specific for Bim(EL) and requires ERK1/2-dependent phosphorylation of Bim(EL) at Ser(65). Finally, ERK1/2-dependent dissociation of Bim(EL) from Mcl-1 and Bcl-x(L) may play a role in regulating Bim(EL) degradation, since mutations in the Bim(EL) BH3 domain that disrupt binding to Mcl-1 cause increased turnover of Bim(EL). These results provide new insights into the role of Bim in cell death and its regulation by the ERK1/2 survival pathway.
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Affiliation(s)
- Katherine E Ewings
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, UK
| | | | - Ceri M Wiggins
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, UK
| | - Julie A Wickenden
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, UK
| | - Kathryn Balmanno
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, UK
| | - Rebecca Gilley
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, UK
| | - Kurt Degenhardt
- Howard Hughes Medical Institute, Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, USA
| | - Eileen White
- Howard Hughes Medical Institute, Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, USA
| | - Simon J Cook
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, UK
- SC dedicates this study to Peter Lockyer who passed away December 28, 2006 and is sorely missed by friends and colleagues alike
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK. Tel.: +44 1223 496453; Fax: +44 1223 496043; E-mail:
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20
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Borensztajn KS, Bijlsma MF, Groot AP, Brüggemann LW, Versteeg HH, Reitsma PH, Peppelenbosch MP, Spek CA. Coagulation factor Xa drives tumor cells into apoptosis through BH3-only protein Bim up-regulation. Exp Cell Res 2007; 313:2622-33. [PMID: 17531220 DOI: 10.1016/j.yexcr.2007.04.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Revised: 04/05/2007] [Accepted: 04/09/2007] [Indexed: 11/19/2022]
Abstract
Coagulation Factor (F)Xa is a serine protease that plays a crucial role during blood coagulation by converting prothrombin into active thrombin. Recently, however, it emerged that besides this role in coagulation, FXa induces intracellular signaling leading to different cellular effects. Here, we show that coagulation factor (F)Xa drives tumor cells of epithelial origin, but not endothelial cells or monocytes, into apoptosis, whereas it even enhances fibroblast survival. FXa signals through the protease activated receptor (PAR)-1 to activate extracellular-signal regulated kinase (ERK) 1/2 and p38. This activation is associated with phosphorylation of the transcription factor CREB, and in tumor cells with up-regulation of the BH3-only pro-apoptotic protein Bim, leading to caspase-3 cleavage, the main hallmark of apoptosis. Transfection of tumor cells with dominant negative forms of CREB or siRNA for either PAR-1, Bim, ERK1 and/or p38 inhibited the pro-apoptotic effect of FXa. In fibroblasts, FXa-induced PAR-1 activation leads to down-regulation of Bim and pre-treatment with PAR-1 or Bim siRNA abolishes proliferation. We thus provide evidence that beyond its role in blood coagulation, FXa plays a key role in cellular processes in which Bim is the central player in determining cell survival.
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Affiliation(s)
- Keren S Borensztajn
- Center for Experimental and Molecular Medicine, Academic Medical Center, Meibergdreef 9, Amsterdam, The Netherlands.
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21
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Chalmers CJ, Gilley R, March HN, Balmanno K, Cook SJ. The duration of ERK1/2 activity determines the activation of c-Fos and Fra-1 and the composition and quantitative transcriptional output of AP-1. Cell Signal 2007; 19:695-704. [PMID: 17052890 DOI: 10.1016/j.cellsig.2006.09.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Accepted: 09/04/2006] [Indexed: 01/20/2023]
Abstract
The duration of ERK1/2 activation influences the nature of the biological response to agonist. Members of the AP-1 transcription factor family are well known targets of the ERK1/2 pathway and are expressed in a temporally coordinated fashion during cell cycle re-entry. In CCl39 fibroblasts, sustained ERK1/2 activation is required for the expression of Fra-1, Fra-2, c-Jun and JunB, whereas expression of c-Fos is still strongly induced even in response to transient ERK activation. However, the significance of this pattern of expression for AP-1 activity has not been addressed. Here we show that growth factor stimulated activation of the C-terminal c-Fos transactivation domain (TAD) serves as a sensor for ERK1/2 signal duration whereas the c-JunTAD is not responsive to growth factors. In addition, sustained ERK1/2 activation determines the duration of increases in AP-1 DNA binding complexes as well as their qualitative make up. Finally, this is reflected in both the duration and quantitative transcriptional output of stably integrated AP-1 reporter constructs, indicating that AP-1 activity is finely tuned to ERK1/2 signal duration. These results provide new insights into the importance of ERK1/2 signal duration in the regulation of AP-1 and provide an explanation for how differences in signal duration can lead to both quantitative and qualitative changes in gene expression.
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Affiliation(s)
- Claire J Chalmers
- Laboratory of Molecular Signalling, The Babraham Institute, Babraham Research Campus, Cambridge, UK
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22
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Coleman LS. A hypothesis: factor VII governs clot formation, tissue repair and apoptosis. Med Hypotheses 2007; 69:903-7. [PMID: 17383108 DOI: 10.1016/j.mehy.2007.01.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2006] [Accepted: 01/24/2007] [Indexed: 11/30/2022]
Abstract
A hypothesis: thrombin is a "Universal Enzyme of Energy Transduction" that employs ATP energy in flowing blood to activate biochemical reactions and cell effects in both hemostasis and tissue repair. All cells possess PAR-1 (thrombin) receptors and are affected by thrombin elevations, and thrombin effects on individual cell types are determined by their unique complement of PAR-1 receptors. Disruption of the vascular endothelium (VE) activates a tissue repair mechanism (TRM) consisting of the VE, tissue factor (TF), and circulating Factors VII, IX and X that governs localized thrombin elevations to activate clot formation and cellular effects that repair tissue damage. The culmination of the repair process occurs with the restoration of the VE followed by declines in thrombin production that causes Apoptosis ("programmed cell death") in wound-healing fibroblasts, which functions as a mechanism to draw wound edges together. The location and magnitude of TRM activity governs the location and magnitude of Factor VIII activity and clot formation, but the large size of Factor VIII prevents it from penetrating the clot formed by its activity, so that its effects are self-limiting. Factors VII, IX and X function primarily as tissue repair enzymes, while Factor VIII and Factor XIII are the only serine protease enzymes in the "Coagulation Cascade" that are exclusively associated with hemostasis.
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23
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Rao HV, Thirumangalakudi L, Desmond P, Grammas P. Cyclin D1, cdk4, and Bim are involved in thrombin-induced apoptosis in cultured cortical neurons. J Neurochem 2007; 101:498-505. [PMID: 17254021 DOI: 10.1111/j.1471-4159.2006.04389.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Thrombin, a multifunctional serine protease, is neurotoxic in vitro and in vivo. Thrombin has been shown to be increased in Alzheimer's disease (AD) and other neuropathological conditions and could be a mediator of pathological neuronal cell death in the brain. The mechanisms of thrombin-induced neuronal cell death are incompletely understood. The objective of this study is to explore mechanisms that contribute to thrombin-induced neuronal apoptosis focusing on the role of cell cycle regulators and the pro-apoptotic protein Bim (Bcl-2-interacting mediator of cell death) in this process. Our data show that thrombin treatment of primary cerebral cortical cultures results in dose-dependent apoptotic cell death. Exposure of neuronal cultures to thrombin leads to induction of cell cycle proteins cyclin D1 and cyclin E, at both mRNA and protein levels. In addition, thrombin treatment causes the appearance of cyclin-dependent kinase 4 (cdk4) and expression of the pro-apoptotic protein Bim. Inhibition of cdk4 prevents both induction of Bim expression and thrombin-induced neuronal apoptosis. These data demonstrate that thrombin-induced apoptosis proceeds via cell cycle activation involving cdk4 resulting in induction of Bim. Thus, cell cycle proteins could be therapeutic targets in diseases such as AD where thrombin has been implicated.
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Affiliation(s)
- Haripriya Vittal Rao
- Garrison Institute on Aging and Department of Neuropsychiatry and Behavioral Sciences, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
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24
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Gorbacheva LR, Storozhevykh TP, Pinelis VG, Ishiwata S, Strukova SM. Modulation of hippocampal neuron survival by thrombin and factor Xa. BIOCHEMISTRY (MOSCOW) 2006; 71:1082-9. [PMID: 17125455 DOI: 10.1134/s000629790610004x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Effects of thrombin, factor Xa (FXa), and protease-activated receptor 1 and 2 agonist peptides (PAR1-AP and PAR2-AP) on survival and intracellular Ca2+ homeostasis in hippocampal neuron cultures treated with cytotoxic doses of glutamate were investigated. It is shown that at low concentrations (<or=10 nM) thrombin and FXa protect neurons from glutamate-induced excitotoxicity. Inactivation of the proteases blocked the neuroprotective effect. Using PAR1-AP, PAR2-AP, and PAR1 antagonist, we have demonstrated that the neuroprotective effect of thrombin is mediated through activation of PAR1, whereas the effect of FXa may involve novel subtype(s) of PARs. Unlike FXa, thrombin induced transient intracellular calcium signal in hippocampal neurons, which was mainly mediated via IP(3) receptors of the endoplasmic reticulum. Both of the serine proteases improved the recovery of neuronal Ca2+ homeostasis after glutamate treatment.
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Affiliation(s)
- L R Gorbacheva
- Department of Human and Animal Physiology, Biological Faculty, Lomonosov Moscow State University, Moscow, 119899, Russia
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25
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Zania P, Kritikou S, Flordellis CS, Maragoudakis ME, Tsopanoglou NE. Blockade of Angiogenesis by Small Molecule Antagonists to Protease-Activated Receptor-1: Association with Endothelial Cell Growth Suppression and Induction of Apoptosis. J Pharmacol Exp Ther 2006; 318:246-54. [PMID: 16595737 DOI: 10.1124/jpet.105.099069] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Many studies support the notion that protease-activated receptor (PAR)-1 plays a pivotal role in angiogenesis. However, direct evidence and understanding the molecular mechanisms involved were limited because PAR-1-specific antagonists have been developed only recently. In the present study, we evaluated the effects of two well characterized PAR-1 antagonists, SCH79797 ((N-3-cyclopropyl-7-{[4-(1-methylethyl)phenyl]-methyl}-7H-pyrrolo[3,2-f]quinazoline-1,3-diamine)) and RWJ56110 [(alphaS)-N-[(1S)-3-amino-1-[[(phenylmethyl)amino]carbonyl]propyl]-alpha-[[[[[1-(2,6-dichlorophenyl)methyl]-3-(1-pyrrolidinylmethyl)-1H-indol-6-yl]amino]carbonyl]amino]-3,4-difluorobenzenepropanamide], in the angiogenic cascade. These antagonists suppressed both the basic angiogenesis and that stimulated by thrombin in the chick chorioallantoic membrane model in vivo. PAR-1 antagonists also abrogated tube formation in the in vitro Matrigel system. These inhibitory effects were dose-dependent and well correlated with the inhibitory effects of SCH79797 and RWJ56110 on primary endothelial cell proliferation and on the initiation of apoptosis. PAR-1 blockage resulted in inhibition of endothelial cell growth by increasing the sub-G0/G1 fraction and reducing the percentage of cells in the S phase. Consistent with this, PAR-1 antagonists reduced incorporation of [3H]thymidine in endothelial cells and blocked the phosphorylation of extracellular signal-regulated kinases in a fashion depending specifically on PAR-1 activation. Analysis by annexin V/propidium iodide staining and poly(ADP-ribose) polymerase cleavage revealed that PAR-1 blockage increased apoptotic cell death by a mechanism involving caspases. These results provide further evidence that PAR-1 is a key receptor that mediates angiogenesis and suggest PAR-1 as target for developing antiangiogenic agents with potential therapeutic application in cancer and other angiogenesis-related diseases.
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Affiliation(s)
- Panagiota Zania
- Department of Pharmacology, Medical School, University of Patras, 26500, Patras, Greece
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26
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Covell DG, Wallqvist A, Huang R, Thanki N, Rabow AA, Lu XJ. Linking tumor cell cytotoxicity to mechanism of drug action: an integrated analysis of gene expression, small-molecule screening and structural databases. Proteins 2006; 59:403-33. [PMID: 15778971 DOI: 10.1002/prot.20392] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
An integrated, bioinformatic analysis of three databases comprising tumor-cell-based small molecule screening data, gene expression measurements, and PDB (Protein Data Bank) ligand-target structures has been developed for probing mechanism of drug action (MOA). Clustering analysis of GI50 profiles for the NCI's database of compounds screened across a panel of tumor cells (NCI60) was used to select a subset of unique cytotoxic responses for about 4000 small molecules. Drug-gene-PDB relationships for this test set were examined by correlative analysis of cytotoxic response and differential gene expression profiles within the NCI60 and structural comparisons with known ligand-target crystallographic complexes. A survey of molecular features within these compounds finds thirteen conserved Compound Classes, each class exhibiting chemical features important for interactions with a variety of biological targets. Protein targets for an additional twelve Compound Classes could be directly assigned using drug-protein interactions observed in the crystallographic database. Results from the analysis of constitutive gene expressions established a clear connection between chemo-resistance and overexpression of gene families associated with the extracellular matrix, cytoskeletal organization, and xenobiotic metabolism. Conversely, chemo-sensitivity implicated overexpression of gene families involved in homeostatic functions of nucleic acid repair, aryl hydrocarbon metabolism, heat shock response, proteasome degradation and apoptosis. Correlations between chemo-responsiveness and differential gene expressions identified chemotypes with nonselective (i.e., many) molecular targets from those likely to have selective (i.e., few) molecular targets. Applications of data mining strategies that jointly utilize tumor cell screening, genomic, and structural data are presented for hypotheses generation and identifying novel anticancer candidates.
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Affiliation(s)
- David G Covell
- National Cancer Institute-Frederick, Developmental Therapeutics Program, Screening Technologies Branch, Laboratory of Computational Technologies, Frederick, Maryland, USA.
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27
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Choy G, Liu JW, Chandra D, Tang DG. Cell survival signaling during apoptosis: implications in drug resistance and anti-cancer therapeutic development. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2006; 63:115-45. [PMID: 16265879 DOI: 10.1007/3-7643-7414-4_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Grace Choy
- Department of Carcinogenesis, the University of Texas M.D. Anderson Cancer Center, Science Park-Research Division, Smithville, TX 78957, USA
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28
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Wang L, Luo J, Fu Y, He S. Induction of interleukin-8 secretion and activation of ERK1/2, p38 MAPK signaling pathways by thrombin in dermal fibroblasts. Int J Biochem Cell Biol 2006; 38:1571-83. [PMID: 16697690 DOI: 10.1016/j.biocel.2006.03.016] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2005] [Revised: 03/12/2006] [Accepted: 03/25/2006] [Indexed: 02/05/2023]
Abstract
It was reported that thrombin could induce IL-8 secretion from human dermal fibroblasts (HDFs) through activation of proteinase activated receptor (PAR)-1. However, little is known of intracellular signaling pathways involved in the event. In the present study, expression of PARs in primarily cultured HDFs was determined by flow cytometry analysis and reverse transcription polymerase chain reaction (RT-PCR), levels of IL-8 were determined by using ELISA and signaling pathways were examined by using Western blot. It was found that HDFs express PAR-1 and PAR-3, and thrombin induces approximately 7.4-fold increase in IL-8 secretion from HDFs. Hirudin and a PAR-1 blocking antibody completely abolish the action of thrombin. It was also found that PD98059, a mitogen-activated protein kinase (MAPK) pathway inhibitor and U0126, an inhibitor of extracellular signal-regulated kinase (ERK) blocks thrombin-induced phosphorylation of ERK1/2 and IL-8 secretion, indicating the involvement of MAPK/ERK signaling pathway in thrombin-induced IL-8 secretion. p38 MAPK pathway appears also being involved as SB203580, a selective inhibitor of p38 MAPK inhibit phosphorylation of p38 MAPK and thrombin-induced IL-8 secretion. Furthermore, Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway, but not phosphotidylinositol 3-kinase (PI3K)/Akt signaling pathway may also be activated by thrombin. In conclusion, thrombin potently induce IL-8 release via PAR-1 from HDFs. Thrombin elicited IL-8 release is predominantly conducted through MAPK/ERK and p38 MAPK signaling pathways. Discovery of the signaling pathways of thrombin in HDFs may help to understand the role of thrombin in inflammation and tissue remodeling.
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Affiliation(s)
- Li Wang
- Allergy and Inflammation Research Institute, The Key Immunopathology Laboratory of Guangdong Province, The Shantou University Medical College, Shantou 515031, China
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29
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Tantivejkul K, Loberg RD, Mawocha SC, Day LL, John LS, Pienta BA, Rubin MA, Pienta KJ. PAR1-mediated NFkappaB activation promotes survival of prostate cancer cells through a Bcl-xL-dependent mechanism. J Cell Biochem 2005; 96:641-52. [PMID: 16052512 DOI: 10.1002/jcb.20533] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We have previously reported that protease-activated receptor 1 (PAR1 or thrombin receptor) is over-expressed in metastatic prostate cancer cell lines compared to prostate epithelial cells. In this study, we examined 1,074 prostate biopsies by tissue microarray analysis and demonstrated that PAR1 expression is significantly increased in prostate cancer compared to normal prostate epithelial cells and benign prostatic hyperplasia. We hypothesized that PAR1 activation contributed to prostate cancer cell progression. We demonstrated that stimulation of PAR1 by thrombin or thrombin receptor activating peptide (TRAP6), in androgen-independent DU145 and PC-3 cells resulted in increased DNA binding activity of the NFkappaB p65 subunit. IL-6 and IL-8 levels were also elevated in conditioned media by at least two-fold within 4-6 h of PAR1 activation. This induction of cytokine production was abrogated by pretreatment of cells with the NFkappaB inhibitor caffeic acid phorbol ester. The p38 and ERK1/2 MAPK signaling cascades were also activated by PAR1 stimulation, whereas the SAPK/JNK pathway was unaffected. Inhibition of p38 and ERK1/2 by SB-203589 and PD-098059, respectively, did not abrogate NFkappaB activity, suggesting an independent induction of NFkappaB by PAR1 stimulation. Furthermore, TUNEL assay showed that activation of PAR1 attenuated docetaxel induced apoptosis through the upregulation of the Bcl-2 family protein Bcl-xL. Akt activation was not observed, suggesting that drug resistance induced by PAR1 was independent of PI3K signaling pathway. Because thrombin and PAR1 are over-expressed in prostate cancer patients, targeting the inhibition of their interaction may attenuate NFkappaB signaling transduction resulting in decreased drug resistance and subsequent survival of prostate cancer cells.
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Affiliation(s)
- Kwanchanit Tantivejkul
- Department of Urology, The Michigan Urology Center, University of Michigan, Ann Arbor, Michigan 48109, USA.
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30
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Lidington EA, Steinberg R, Kinderlerer AR, Landis RC, Ohba M, Samarel A, Haskard DO, Mason JC. A role for proteinase-activated receptor 2 and PKC-epsilon in thrombin-mediated induction of decay-accelerating factor on human endothelial cells. Am J Physiol Cell Physiol 2005; 289:C1437-47. [PMID: 16079188 DOI: 10.1152/ajpcell.00502.2004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Thrombin, an important mediator of thrombosis and inflammation, may also enhance vascular cytoprotection. Thus thrombin induces expression of the complement-inhibitory protein decay-accelerating factor (DAF) in human umbilical vein endothelial cells (HUVECs), thus increasing protection against complement-mediated injury. Using PKC isozyme-specific peptide antagonists and adenoviral constructs, we have shown in the present study that PKC-epsilon is the primary isozyme involved in DAF induction by thrombin. Experiments with proteinase-activated receptor-1 (PAR1) and PAR2 activating peptides (APs) showed that DAF expression induced by PAR1-AP was PKC-alpha-dependent; in contrast, PAR2-AP induction of DAF required activation of PKC-epsilon. PAR1-AP and PAR2-AP in combination exerted an additive effect on DAF protein expression, which was equivalent to that observed with thrombin alone. These data implied a specific role for PAR2 in DAF induction, which was supported by the observation that upregulation of endothelial cell (EC) PAR2-enhanced DAF induction by thrombin. ERK1/2, p38, and JNK MAPK were also involved in thrombin-induced DAF upregulation, with evidence of interdependence between ERK1/2 and JNK. A role for transactivation of PAR2 by PAR1 was suggested by partial inhibition of thrombin-induced DAF expression by the PAR1 signaling antagonists BMS-200261 and SCH79797, whereas inhibition of thrombin-induced cleavage of PAR1 by specific MAbs or hirudin completely abrogated the response. Together, these data imply that the predominant pathway for thrombin-induced DAF expression involves transactivation of PAR2 by PAR1 and signaling via PKC-epsilon/MAPK. This may represent an important, novel pathway for endothelial cytoprotection during inflammation and angiogenesis and suggests that PAR2 may play a central role in some thrombin-induced responses.
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Affiliation(s)
- Elaine A Lidington
- Cardiovascular Medicine Unit, Imperial College, Hammersmith Hospital, DuCane Road, London W12 ONN, UK
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31
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Suzuki T, Moraes TJ, Vachon E, Ginzberg HH, Huang TT, Matthay MA, Hollenberg MD, Marshall J, McCulloch CAG, Abreu MTH, Chow CW, Downey GP. Proteinase-activated receptor-1 mediates elastase-induced apoptosis of human lung epithelial cells. Am J Respir Cell Mol Biol 2005; 33:231-47. [PMID: 15891109 PMCID: PMC2715314 DOI: 10.1165/rcmb.2005-0109oc] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Apoptosis of distal lung epithelial cells plays a pivotal role in the pathogenesis of acute lung injury. In this context, proteinases, either circulating or leukocyte-derived, may contribute to epithelial apoptosis and lung injury. We hypothesized that apoptosis of lung epithelial cells induced by leukocyte elastase is mediated via the proteinase activated receptor (PAR)-1. Leukocyte elastase, thrombin, and PAR-1-activating peptide, but not the control peptide, induced apoptosis in human airway and alveolar epithelial cells as assessed by increases in cytoplasmic histone-associated DNA fragments and TUNEL staining. These effects were largely prevented by a specific PAR-1 antagonist and by short interfering RNA directed against PAR-1. To ascertain the mechanism of epithelial apoptosis, we determined that PAR-1AP, thrombin, and leukocyte elastase dissipated mitochondrial membrane potential, induced translocation of cytochrome c to the cytosol, enhanced cleavage of caspase-9 and caspase-3, and led to JNK activation and Akt inhibition. In concert, these observations provide strong evidence that leukocyte elastase mediates apoptosis of human lung epithelial cells through PAR-1-dependent modulation of the intrinsic apoptotic pathway via alterations in mitochondrial permeability and by modulation of JNK and Akt.
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Affiliation(s)
- Tomoko Suzuki
- Division of Respirology, Department of Medicine, University of Toronto and Toronto General Hospital Research Institute, 1 King's College Circle, Toronto, Ontario, M5S 1A8 Canada
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Bhat GJ, Samikkannu T, Thomas JJ, Thekkumkara TJ. alpha-thrombin rapidly induces tyrosine phosphorylation of a novel, 74-78-kDa stress response protein(s) in lung fibroblast cells. J Biol Chem 2004; 279:48915-22. [PMID: 15364938 DOI: 10.1074/jbc.m409043200] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We demonstrated previously that exposure of CCL39 lung fibroblasts to alpha-thrombin rapidly inhibits interleukin 6-induced tyrosine phosphorylation of signal transducers and activators of transcription 3 (Stat3). While studying the cross-talk between alpha-thrombin and interleukin 6, we observed that the phospho-specific (tyrosine) anti-Stat3 antibody specifically cross-reacted with a 74-78-kDa protein(s) in alpha-thrombin-treated cells. In this study, we demonstrate that in alpha-thrombin-treated CCL39 cells, the 74-78-kDa protein(s) rapidly undergoes tyrosine phosphorylation. The phosphorylation by alpha-thrombin was detected as early as 5 min and reached a maximum at 15 min; however, low levels were present at 2 h. alpha-Thrombin receptor agonist peptide (SFLLRN) induced its tyrosine phosphorylation, suggesting that alpha-thrombin mediates the effects via protease-activated receptor type 1. Anti-Stat3 antibodies specific to different regions of Stat3 failed to recognize the 74-78-kDa protein(s), suggesting that it is unrelated to Stat3. Cell fractionation experiments showed that it is localized to the cytoplasm. Mass spectrometric analysis of the immunoprecipitated protein showed that the 74-78-kDa protein(s) is related to glucose-regulated protein 75 (GRP-75), a member of the heat shock/stress-response protein family. Consistent with these data, we observed tyrosine phosphorylation of GRP-75 in alpha-thrombin-treated cells. Exposure of cells to pervanadate, a stress-inducing agent, stimulated its tyrosine phosphorylation; however, cytokines and growth factors were ineffective. This is the first report of tyrosine phosphorylation of GRP-75-related stress protein(s) by alpha-thrombin and suggests that this pathway may contribute to the ability of alpha-thrombin to prevent apoptosis in cells exposed to stress or in the injured tissue.
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Affiliation(s)
- G Jayarama Bhat
- Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, Texas 79106, USA.
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Wynes MW, Frankel SK, Riches DWH. IL-4-induced macrophage-derived IGF-I protects myofibroblasts from apoptosis following growth factor withdrawal. J Leukoc Biol 2004; 76:1019-27. [PMID: 15316031 DOI: 10.1189/jlb.0504288] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The development of idiopathic pulmonary fibrosis (IPF) is associated with myofibroblast accumulation and collagen deposition in the lung parenchyma. Recent studies have suggested that the fibroproliferative response is associated with immune deviation toward a T helper cell type 2 (Th2) cytokine profile. In addition, myofibroblast accumulation may be the result of resistance to physiologic apoptosis. If and how these events are linked remain largely unknown. Insulin-like growth factor-I (IGF-I) is a fibroblast growth and survival factor that has long been implicated in the pathogenesis of IPF. We have previously shown that interstitial macrophage-derived IGF-I correlates with disease severity in IPF, and the Th2 cytokines interleukin (IL)-4 and IL-13 stimulate the expression and secretion of IGF-I by macrophages. In the present study, we tested the hypothesis that IL-4-induced, macrophage-derived IGF-I protects myofibroblasts from apoptosis. Using a growth factor withdrawal model of apoptosis in the myofibroblast cell line, CCL39, we demonstrate that conditioned media from IL-4-stimulated macrophages protect myofibroblasts from apoptosis. The survival effect is lost when IGF-I is immunodepleted from macrophage-conditioned media with IGF-I-specific antibodies. We also show that the protection of myofibroblasts by macrophage-derived IGF-I correlates with and is dependent on the activation of the prosurvival kinases Akt and extracellular signal-regulated kinase. These findings support the view that IL-4-stimulated, macrophage-derived IGF-I may contribute to the persistence of myofibroblasts in pulmonary fibrosis in the Th2-deviated environment of the fibrotic lung.
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Affiliation(s)
- Murry W Wynes
- Program of Cell Biology, Department of Pediatrics, National Jewish Medical and Research Center, Denver, CO 80206, USA
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Shi X, Gangadharan B, Brass LF, Ruf W, Mueller BM. Protease-Activated Receptors (PAR1 and PAR2) Contribute to Tumor Cell Motility and Metastasis. Mol Cancer Res 2004. [DOI: 10.1158/1541-7786.395.2.7] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The effects of the pleiotropic serine protease thrombin on tumor cells are commonly thought to be mediated by the thrombin receptor protease-activated receptor 1 (PAR1). We demonstrate here that PAR1 activation has a role in experimental metastasis using the anti-PAR1 antibodies ATAP2 and WEDE15, which block PAR1 cleavage and activation. Thrombin also stimulates chemokinesis of human melanoma cells toward fibroblast conditioned media and soluble matrix proteins. Thrombin-enhanced migration is abolished by anti-PAR1 antibodies, demonstrating that PAR1 cleavage and activation are required. The PAR1-specific agonist peptide TFLLRNPNDK, however, does not stimulate migration, indicating that PAR1 activation is not sufficient. In contrast, a combination of TFLLRNPNDK and the PAR2 agonist peptide SLIGRL mimics the thrombin effect on migration, whereas PAR2 agonist alone has no effect. Agonist peptides for the thrombin receptors PAR3 and PAR4 used alone or with PAR1 agonist also have no effect. Similarly, activation of PAR1 and PAR2 also enhances chemokinesis of prostate cancer cells. Desensitization with PAR2 agonist abolishes thrombin-enhanced cell motility, demonstrating that thrombin acts through PAR2. PAR2 is cleaved by proteases with trypsin-like specificity but not by thrombin. Thrombin enhances migration in the presence of a cleavage-blocking anti-PAR2 antibody, suggesting that thrombin activates PAR2 indirectly and independent of receptor cleavage. Treatment of melanoma cells with trypsin or PAR2 agonist peptide enhances experimental metastasis. Together, these data confirm a role for PAR1 in migration and metastasis and demonstrate an unexpected role for PAR2 in thrombin-dependent tumor cell migration and in metastasis.
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Affiliation(s)
- Xiaoli Shi
- 1Cancer Biology Division, La Jolla Institute for Molecular Medicine, San Diego, California
| | - Beena Gangadharan
- 1Cancer Biology Division, La Jolla Institute for Molecular Medicine, San Diego, California
| | - Lawrence F. Brass
- 2Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; and
| | - Wolfram Ruf
- 3Department of Immunology, Scripps Research Institute, La Jolla, California
| | - Barbara M. Mueller
- 1Cancer Biology Division, La Jolla Institute for Molecular Medicine, San Diego, California
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Rössler OG, Thiel G. Brain-derived neurotrophic factor-, epidermal growth factor-, or A-Raf-induced growth of HaCaT keratinocytes requires extracellular signal-regulated kinase. Am J Physiol Cell Physiol 2004; 286:C1118-29. [PMID: 15075211 DOI: 10.1152/ajpcell.00301.2003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The epidermal growth factor (EGF) receptor plays an important role in epithelial cells by controlling cell proliferation and survival. Keratinocytes also express another class of receptor tyrosine kinases, the neurotrophin receptors. To analyze the biological role of the neurotrophin brain-derived neurotrophic factor (BDNF) in keratinocytes, we expressed the BDNF receptor TrkB in immortalized human HaCaT keratinocytes. Stimulation of HaCaT-TrkB cells with BDNF induced DNA synthesis and increased mitochondrial reduction capacities, both indications of proliferating cells. An analysis of the signal transduction cascade revealed that the activated TrkB receptor effectively utilized components of the EGF receptor signaling pathway to control cell proliferation. Mitogenic signaling induced by BDNF or EGF was completely abrogated by the MAP kinase kinase inhibitor PD-98059, whereas inhibition of phosphatidylinositol 3-kinase by wortmannin only delayed the proliferative response. The importance of the extracellular signal-regulated kinase signaling pathway for growth of HaCaT keratinocytes was further demonstrated with HaCaT cells engineered to express an inducible A-Raf-estrogen receptor fusion protein (ΔA-Raf:ER). Despite differences in the amplitude and duration of extracellular signal-regulated kinase activation, HaCaT cells expressing ΔA-Raf:ER proliferated after activation of mutant A-Raf protein kinase. Proliferation was completely inhibited by PD-98059. Proliferation of HaCaT cells induced by EGF, BDNF, or ΔA-Raf:ER was also accompanied by biosynthesis of the transcription factors Egr-1 and c-Jun, suggesting that these proteins may be part of the mitogenic signaling cascade.
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Affiliation(s)
- Oliver G Rössler
- Dept. of Medical Biochemistry and Molecular Biology, Bldg. 44, Univ. of Saarland Medical Center, D-66421 Homburg, Germany
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