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βig-h3 is a TGF-β (transforming growth factor β)-induced ECM (extracellular matrix) protein that induces the secretion of MMPs (matrix metalloproteinases). However, the mechanism of induction is yet to be established. In this study, siRNAs (small interfering RNAs) targeted against βig-h3 were transfected into SMMC-7721 cells [a HCC (human hepatocellular carcinoma) cell line] to knockdown the expression of βig-h3. We found that NiCl2, a potent blocker of extracellular Ca2+ entry, reduced βig-h3-induced secretion of MMP-2 and -9. Further investigation suggested that reduction in the levels of βig-h3 decreased the secretion of MMP-2 and -9 that was enhanced by an increase in the concentration of extracellular Ca2+. SNAP (S-nitroso-N-acetylpenicillamine), a NO (nitric oxide) donor, and 8-Br-cGMP (8-bromo-cGMP) inhibited thapsigargin-induced Ca2+ entry and MMP secretion in the invasive potential of human SMMC-7721 cells. Further, the inhibitory effects of 8-Br-cGMP and SNAP could be significantly enhanced by down-regulating βig-h3. βig-h3 attenuates the negative regulation of NO/cGMP-sensitive store-operated Ca2+ entry. Our findings suggest that the expression of βig-h3 might play an important role in the regulation of store-operated Ca2+ entry to increase the invasive potential of HCC cells.  相似文献   

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While epidermal growth factor receptor (EGFR) plays a pivotal role in the repair process of epithelial cells, it is also involved in the overproduction of mucus and goblet cell hyperplasia (GCH), which occurs in chronic airway diseases such as asthma. Among the EGFR ligands, transforming growth factor (TGF)-α is thought to be the most important in the synthesis of mucus. Pro-TGF-α is cleaved to give an active form by members of the matrix metalloproteinases (MMP)/a disintegrin and metalloproteinases (ADAM) family. Thus MMP/ADAM inhibitors might prevent GCH by inhibiting transactivation of EGFR. Upon stimulation of differentiating normal human bronchial epithelial (NHBE) cells by IL-13, GCH was induced. The mucin genes MUC5AC, MUC5B, and MUC2 were upregulated whereas the expression of ciliated cell markers was greatly repressed. GM6001, a broad-spectrum inhibitor for MMP/ADAM, inhibited IL-13-induced mucin gene expression and mucus production as measured by periodic acid-Schiff staining. This was accompanied by an inhibition of TGF-α release. These results suggest that MMP/ADAMs play a pivotal role in the development of GCH in lung epithelial cells.  相似文献   

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Matrix metalloproteinases (MMPs) are a family of zinc‐dependent endopeptidases that degrade extracellular matrix components and play important roles in a variety of biological and pathological processes such as malignant tumor metastasis and invasion. In this study, we constructed carnosine–gallic acid peptide (CGP) to identify a better MMP inhibitor than carnosine. The inhibitory effects of CGP on MMP‐2 and MMP‐9 were investigated in the human fibrosarcoma (HT1080) cell line. As a result, CGP significantly decreased MMP‐2 and MMP‐9 expression levels without a cytotoxic effect. Moreover, CGP may inhibit migration and invasion in HT1080 cells through the urokinase plasminogen activator (uPA)–uPA receptor signaling pathways to inhibit MMP‐2 and MMP‐9. Based on these results, it appears that CGP may play an important role in preventing and treating several MMP‐2 and MMP‐9‐mediated health problems such as metastasis. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

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Matrix metalloproteinase-28 (MMP-28, epilysin) is highly expressed in the skin by keratinocytes, the developing and regenerating nervous system and a number of other normal human tissues. In epithelial cells, over-expression of MMP-28 mediates irreversible epithelial to mesenchymal transition concomitant with loss of E-cadherin from the cell surface and an increase in active transforming growth factor beta. We recently reported the expression of MMP-28 in both cartilage and synovium where expression is increased in patients with osteoarthritis.In human chondrosarcoma cells MMP-28 was activated by proprotein convertases and the active form of the enzyme preferentially associated with the extracellular matrix in a C-terminal independent manner. over-expression of MMP-28 in chondrosarcoma cells led to altered cell morphology with increased organisation of actin. Adhesion to type II collagen and fibronectin was increased, and migration across the former was decreased. MMP-28 was localised to the cell surface, at least transiently, in a C-terminal dependent manner. Heparin prevented both extracellular matrix association and cell surface binding of MMP-28 suggesting that both are via heparan sulphate proteoglycans. Over-expression of activatable MMP-28, but not catalytically inactive EA mutant increased the expression and activity of MMP-2, and all forms of MMP-28 tested increased expression of MMP19 and TIMP3 mRNA.These data demonstrate that expression of MMP28 alters cell phenotype towards a more adhesive, less migratory behaviour. Further, MMP-28 activity may reside predominantly in the extracellular matrix, and we are currently searching for substrates in this compartment.  相似文献   

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Colon carcinoma invasiveness is a process involving cell–cell and cell–matrix alterations, local proteolysis of the ECM (extracellular matrix) or changes in cytokine and growth factor levels. In order to evaluate the role of TGF‐β1 (transforming growth factor‐β1) and small G protein RhoA in tumour progression, the influence of TGF‐β1 treatment or RhoA‐associated kinase inhibitor on the production of NO (nitric oxide) and MMP‐2 and MMP‐9 (metalloproteinases‐2 and ‐9) was analysed in three human colon adenocarcinoma cell lines (HT29, LS180, SW948) representing different stages of tumour development. All the tested cell lines produced low amounts of MMP‐2 and MMP‐9. rhTGF‐β1 and the synthetic Rho kinase inhibitor (Y‐27632) decreased MMP‐2 secretion by colon cancer cells, especially in the most advanced stage of colon cancer. rhTGF‐β1 decreased NO secretion by cells, while Y‐27632 had no effect on it. Immunoblotting with anti‐RhoA antibodies followed by densitometry revealed that RhoA levels were slightly increased after incubation of colon carcinoma cells (SW948) with rhTGF‐β1. rhTGF‐β1 induced α‐smooth muscle actin (α‐SMA) expression, especially in high Duke's grade of colon cancer, while Y‐27632 blocked it. Summing up, in colon carcinoma cells, TGF‐β1 and RhoA protein may regulate tumour invasiveness measured as MMP, NO and α‐SMA expression or assayed using motility data and may be a good target for cancer therapy.  相似文献   

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Rubus coreanus Miquel (RCM) is used to promote prostate health and has been shown to have anti-oxidant and anti-carcinogenic activities. However, the effects and mechanisms of RCM on prostate cancer metastasis remain unclear. PC-3 and DU 145 cells were treated with ethanol or water extract of unripe or ripe RCM and examined for cell invasion, migration, and matrix metalloproteinases (MMPs) activity and expression. Phosphoinositide 3-kinase (PI3K) and Akt activities were examined. Unripe RCM extracts exerted significant inhibitory effects on cell migration, invasion, and MMPs activities. A significant reduction in MMPs activities by unripe RCM ethanol extract treatment (UE) was associated with reduction of MMPs expression and induction of tissue inhibitors of metalloproteinases (TIMPs) expression. Furthermore, PI3K/Akt activity was diminished by UE treatment. In this study, we demonstrated that UE decreased metastatic potential of prostate cancer cells by reducing MMPs expression through the suppression of PI3K/Akt phosphorylation, thereby decreasing MMP activity and enhancing TIMPs expression.  相似文献   

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In the mouse, the sex determining gene Sry, on the Y chromosome, controls testis differentiation during embryogenesis. Following Sry expression, indifferent XY gonads increase their size relative to XX gonads and form cord-like structures with the adjacent mesonephros, providing XY gonad somatic cells. This mesonephric cell migration is known to depend on Sry, but the molecular mechanism of mesonephric cell migration remains unknown. In this study, it was shown that cells expressing Sry induced proliferation of mesonephric cells migrating into male gonads, and inhibited expression of the tissue inhibitor of metalloproteinases (TIMP)-3 gene, which is the endogenous inhibitor of matrix metalloproteinases (MMP). In addition, the mesonephric cell migration was blocked by a chemically synthesized inhibitor of MMP in a gonad/mesonephros organ co-culture system with enhanced green fluorescent protein transgenic embryos. The findings indicate that MMP may play a critical role in mesonephric cell migration, and the function of MMP may be regulated by a Sry-TIMP-3 cascade. These findings are an important clue for the elucidation of testicular formation in developing gonads.  相似文献   

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Tissue inhibitor of metalloproteinase (TIMP-1) is a natural protease inhibitor of matrix metalloproteinases (MMPs). Recent studies revealed a novel function of TIMP-1 as a potent inhibitor of apoptosis in mammalian cells. However, the mechanisms by which TIMP-1 exerts its anti-apoptotic effect are not understood. Here we show that TIMP-1 activates cell survival signaling pathways involving focal adhesion kinase, phosphatidylinositol 3-kinase, and ERKs in human breast epithelial cells to TIMP-1. TIMP-1-activated cell survival signaling down-regulates caspase-mediated classical apoptotic pathways induced by a variety of stimuli including anoikis, staurosporine exposure, and growth factor withdrawal. Consistently, down-regulation of TIMP-1 expression greatly enhances apoptotic cell death. In a previous study, substitution of the second amino acid residue threonine for glycine in TIMP-1, which confers selective MMP inhibition, was shown to obliterate its anti-apoptotic activity in activated hepatic stellate cells suggesting that the anti-apoptotic activity of TIMP-1 is dependent on MMP inhibition. Here we show that the same mutant inhibits apoptosis of human breast epithelial cells, suggesting different mechanisms of TIMP-1 regulation of apoptosis depending on cell types. Neither TIMP-2 nor a synthetic MMP inhibitor protects breast epithelial cells from intrinsic apoptotic cell death. Furthermore, TIMP-1 enhances cell survival in the presence of the synthetic MMP inhibitor. Taken together, the present study unveils some of the mechanisms mediating the anti-apoptotic effects of TIMP-1 in human breast epithelial cells through TIMP-1-specific signal transduction pathways.  相似文献   

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目的:建立由猪肝组织制备肝脱细胞基质溶液的新方法,并研究基质溶液包被对人肝癌细胞HepG2增殖及基质金属蛋白酶活性的影响。方法:对猪肝脏进行脱细胞处理,经研磨、冻干及胃蛋白酶消化制备肝脱细胞基质溶液,利用此基质溶液包被聚苯乙烯培养表面,进行HepG2细胞体外培养,并使用CCK-8、实时定量PCR、明胶酶谱等检测细胞增殖以及基质金属蛋白酶的基因表达和活性。结果:建立了由猪肝组织制备肝脱细胞基质溶液的新方法。与未包被组相比,脱细胞基质溶液包被培养显著促进HepG2细胞增殖,其细胞周期蛋白cyclin D1的基因表达增高,为未包被组的1.95倍(P0.01)。此外,脱细胞基质溶液包被组HepG2细胞的MMP14基因表达为未包被组的2.01倍(P0.05),明胶酶谱检测基质溶液包被组细胞的MMP9活性为未包被组的6.66倍(P0.01)。结论:肝脱细胞基质溶液包被培养可显著促进HepG2细胞增殖并提高其MMP9的活性,在构建模拟肝癌微环境培养体系中具有一定的应用潜力。  相似文献   

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The P2X7 receptor is an ion‐gated channel, which is activated by high extracellular concentrations of adenosine triphosphate (ATP). Activation of P2X7 receptors has been shown to induce neuroinflammatory changes associated with several neurological conditions. The matrix metalloproteinases (MMPs) are a family of endopeptidases that have several functions including degradation of the extracellular matrix, cell migration and modulation of bioactive molecules. The actions of MMPs are prevented by a family of protease inhibitors called tissue inhibitors of metalloproteinases (TIMPs). In this study, we show that ATP‐treated glial cultures from neonatal C57BL/6 mice release and increase MMP‐9 activity, which is coupled with a decrease in release of TIMP‐1 and an increase in activated cathepsin B within the extracellular space. This process occurs independently of NLRP3‐inflammasome formation. Treatment with a P2X7 receptor antagonist prevents ATP‐induced MMP‐9 activity, inhibition of active cathepsin B release and allows for TIMP‐1 to be released from the cell. We have shown that cathepsin B degrades TIMP‐1, and inhibition of cathepsin B allows for release of TIMP‐1 and inhibits MMP‐9 activity. We also present data that indicate that ATP or cell damage induces glial cell migration, which is inhibited by P2X7 antagonism, depletion of MMP‐9 or inhibition of cathepsin B.  相似文献   

14.
Hypoxia not only controls organogenesis, embryogenesis, and wound repair, but also triggers tumor progression and metastasis. Matrix metalloproteinases (MMP), especially gelatinases (MMP-2, MMP-9) regulate the composition and stability of the extracellular matrix (ECM), which affects cell proliferation, migration, and differentiation. This study investigated the effect of hypoxia alone and in combination with ECM compounds and nutrition on MMP-2 and MMP-9 expression, activity, and synthesis in human lung fibroblasts and pulmonary vascular smooth muscle cells (VSMC). We also determined the expression of the tissue inhibitors of MMP (TIMP-1, -2). Cells were grown on plastic, collagen-I, collagen-IV, or gelatin and in either starving medium (0.1% serum) or growth medium (5% serum), and were subjected to normoxia or hypoxia (1% O(2)). Collagenases expression was determined by zymography. TIMP-1, -2 expression was assessed by Western blotting and RT-PCR. Depending on serum concentration human lung cells expressed pro-MMP-2 on all substrates. Hypoxia increased pro-MMP-2 expression, on collagen type I or type IV further via Erk1/2 and p38 MAP kinase signaling. MMP-9 was only expressed when cells were grown on collagen type IV and increased with serum concentration, and by hypoxia. TIMP-1 expression was only expressed when cells were grown on collagen type I and was significantly increased by hypoxia, while TIMP-2 expression was unchanged. We demonstrated that the hypoxia, ECM composition, and nutrition, rather than one of these conditions alone, modulate the expression and activity of collagenases and their inhibitors in primary human lung fibroblasts.  相似文献   

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During an inflammatory response, resident and newly recruited tissue macrophages adhere to extracellular matrix and cell-bound integrin ligands. This interaction induces the expression of pro-inflammatory mediators that include matrix metalloproteinases (MMPs). Arhgef1 is an intracellular signaling molecule expressed by myeloid cells that normally attenuates murine macrophage MMP production in vivo and in vitro after cell culture on the extracellular matrix protein, fibronectin. In this study, we have extended the characterization of this fibronectin-induced Arhgef1-regulated signaling pathway in both human and murine myeloid cells. Our results show that MMP9 production by fibronectin-stimulated monocytes and macrophages depends on autocrine thromboxane receptor signaling and that under normal conditions, this signaling pathway is attenuated by Arhgef1. Finally, we show that the expression of ARHGEF1 by human peripheral blood monocytes varies between individuals and inversely correlates with fibronectin-mediated MMP9 production.  相似文献   

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The study intends to investigate the regulation of syndecan-1 in human uterine leiomyoma cells. Human syndecan-1 levels were detected by Western blot in uterus leimyoma''s tissue. The efficacy of syndecan-1 silencing on the cell proliferation, metalloproteinases and extracellular matrix were determined through Cell Counting Kit (CCK8) assay and Western blot assay, respectively. We compared the respective and combined effect of mifepristone and syndecan-1 on cell proliferation and the expression of metalloproteinases and extracellular matrix (ECM) in human uterine leiomyoma cells. The inhibitory effects of Syndecan-1 silencing on proliferation, ECM and Matrix Metalloproteinase (MMP) were observed in human uterine leiomyoma cells. Furthermore, syndecan-1 inhibition enhanced the effects of mifepristone against uterine leiomyoma cell proliferation. The expression of MMPs and ECM components in human uterine leiomyoma cells was decreased dramatically after syndecan-1 silencing, which was promoted after mifepristone treatment. Altogether, syndecan-1 silencing enhanced the efficacy of mifepristone on the uterine leiomyoma cell proliferation and ECM formation. Therefore, targeting syndecan-1 represents a novel therapeutic strategy to treat uterine leiomyoma.  相似文献   

18.
Migration and invasion are prerequisites for the neoplastic phenotype of malignant glioma. Ectopic expression of BCL-2 enhances migration and invasion of glioma cells and promotes their synthesis of transforming growth factor-beta2 (TGF-beta2). We here report that BCL-2-expressing cells show enhanced expression and activity of the proprotein convertase, furin, which processes metalloproteinases (MMP) and TGF-beta. Consistent with a biological role for a BCL-2-dependent increase in furin-like protease (FLP) activity, BCL-2-expressing cells exhibit enhanced MMP activity. Both a pseudosubstrate furin inhibitor, decanoyl-Arg-Val-Lys-Arg-chloromethylketone (dec-RVKR-cmk), or alpha 1-anti-trypsin Portland (PDX), a recombinant furin-inhibitory protein, suppress constitutive and BCL-2-mediated MMP activity and invasion. This inhibition is not overcome by TGF-beta or hepatocyte growth factor (HGF). A neutralizing TGF-beta antibody attenuates, but not abrogates, the invasive properties conferred by exogenous expression of BCL-2, whereas the MMP inhibitor o-phenantroline (o-PA) abolishes the pro-invasive action of BCL-2. Exogenous HGF results in enhanced, and expression of dominant-negative ezrin in reduced, FLP activity, and dec-RVKR-cmk blunts the HGF-induced expression of mature TGF-beta2. Consequently, HGF and BCL-2 family proteins use a furin-dependent pathway to promote invasion via TGF-beta and MMP in human malignant glioma cells and the pro-invasive properties of TGF-beta require furin- dependent MMP activity.  相似文献   

19.
In chronic congestive heart failure, an illness affecting more than 4 million Americans, there is impairment of myocardial extracellular matrix (ECM) remodeling. Failing human ventricular myocardium contains activated matrix metalloproteinases (MMPs), which are involved in adverse ECM remodeling. Our studies support the concept that impaired ECM remodeling and MMP activation are, in part, responsible for the cardiac structural deformation and heart failure. There is no known program that has declared its aim the investigation of the role of ECM gene therapy in heart failure. The development of transgenic technology, and emerging techniques for in vivo gene transfer, suggest a strategy for improving cardiac function by overexpressing or downregulation of the ECM components such as MMPs, tissue inhibitor of metalloproteinases (TIMPs), transforming growth factor-β1 (TGF-β), decorin, and collagen in cardiomyopathy and heart failure. J. Cell. Biochem. 68:403–410, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

20.
Cell-matrix interactions transmit a wealth of information about the extracellular environment. In return, a variety of responses from the cell are initiated by changes in the matrix. One such response involves the positive regulation of matrix metalloproteinases (MMPs) by alpha2beta1 integrin attaching to a specific extracellular matrix component, collagen. This study explores the relationship between mechanical and biochemical functions of alpha2beta1 integrins as it pertains to regulating matrix remodeling. To understand this relationship, the individual influences of MMP activity and alpha2beta1 integrin function on collagen gel contraction were studied. We have observed little evidence of mutual participation in matrix remodeling by the alpha2beta1 integrin and MMP activity in cell models where alpha2 is minimally expressed. In cells expressing high levels of alpha2, we see an increase in gel contraction that is enhanced by MMP activity. Measuring tension as it builds within the gel reveals that alpha2beta1 integrin presence correlates with force output but is insensitive to MMP activity. These data strongly suggest that alpha2beta1 regulates collagen gel remodeling through multiple simultaneous mechanisms including force generation and modulation of MMP activity.  相似文献   

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