Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.35 (matrix metalloproteinase 9)
 2,207 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human umbilical vein endothelial cells (HUVECs) invade collagen gels and establish vascular-like structures within the gel following stimulation with phorbol esters. This process was quantitated by measuring release of radioactivity from gels composed of [3H]collagen. Collagen was steadily degraded over the period of several weeks by phorbol ester-treated cells while little collagenolysis by cells not receiving phorbol ester was noted. Examination of matrix metalloproteinases (MMPs) secreted by HUVECs revealed a prominent induction of interstitial collagenase. Production of the mature forms of gelatinase A was also stimulated, as was the secretion of gelatinase B. Stromelysin was not detected. Two inhibitors of MMPs, the naturally occurring tissue inhibitor of metalloproteinases (TIMP; 10 micrograms/ml) and the synthetic, peptide inhibitor BB-94 (1 microM) were both effective at blocking HUVEC-mediated collagen degradation. Morphological examination of control, PMA-treated HUVECs, as well as PMA-treated HUVECs receiving TIMP or BB-94, revealed that MMP inhibition resulted in a block to invasion and tubule formation within the collagen gels. Similar results for MMP expression and inhibition of tubule formation in vitro were obtained with human dermal microvascular endothelial cells. Examination of collagen proteolytic fragments revealed that both BB-94 and TIMP blocked cleavage of the alpha 1 and alpha 2 chains of type I collagen and the appearance of tropocollagen fragments A and B, demonstrating that the inhibitors were acting directly upon interstitial collagenase. Our results demonstrate that interstitial collagenase is required for angiogenesis in vitro.
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PMID:Interstitial collagenase is required for angiogenesis in vitro. 751 58

Matrix metalloproteinases (MMPs) are a family of inducible enzymes that degrade extracellular matrix components, allowing cells to traverse connective tissue structures efficiently. Specific tissue inhibitors (TIMPs) function as physiologic inhibitors of MMP activity. Because neovascularization may require various proteinases, we characterized the profile of metalloenzyme production by microvascular endothelial cells (MEC) and the modulation of expression by phorbol esters (PMA) and by the physiologically relevant cytokines tumor necrosis factor-alpha (TNF-alpha), basic fibroblast growth factor, and interferon-gamma. MMP expression by MEC and large-vessel human umbilical vein endothelial cells (HUVEC) was determined by enzyme-linked immunosorbent assay, immunoprecipitation, Northern hybridization, and transfection assays. Constitutive expression of MMPs by endothelial cells was low. PMA stimulated the production of collagenase, stromelysin, 92-kDa gelatinase, and TIMP-1 in both endothelial cell types. TIMP-2 was constitutively expressed by MEC and HUVEC, but was down-regulated by PMA. TNF-alpha induced an endothelial-cell-specific up-regulation of collagenase with a concomitant inhibition of PMA-induced TIMP-1 up-regulation, a response that is distinct from that of fibroblasts. Interferon-gamma up-regulated TIMP-1 production by MEC and blocked PMA and TNF-induced up-regulation of collagenase. Northern hybridization assays showed pretranslational control of PMA-, basic fibroblast growth factor-, and TNF-alpha-induced MMP expression. Collagenase-promoter CAT constructs containing 2.28 kb of the 5' region of the collagenase gene demonstrated transcriptional regulation. The potential physiologic relevance of such regulation was shown in an in vitro migration assay. MEC were stimulated to migrate by wounding and exposure to TNF-alpha. Collagenase mRNA was prominently expressed by the migrating cells, as shown by in situ hybridization. In sum, MEC have a unique profile of MMP expression and regulation compared with other cell types, which may be important for wound healing and angiogenesis, particularly during the early phase of migration.
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PMID:Human dermal microvascular endothelial cells produce matrix metalloproteinases in response to angiogenic factors and migration. 754 47

The present study was undertaken to determine the role of the metalloproteinase MMP-9 in the invasive phenotype of squamous-cell carcinoma of the oral cavity and the regulation of its expression. Zymographic analysis of conditioned medium from 2 highly invasive squamous-cell-carcinoma cell lines indicated large amounts of an enzyme which was indistinguishable, in size (92 kDa) from the MMP-9 pro-enzyme. Conversion of the 92-kDa gelatinase into a lower-molecular-weight species (84 kDa), identical in size to the activated gelatinase, was evident when both cell lines, which are avid secretors of urokinase, were cultured in the presence of plasminogen. Penetration of an extracellular-matrix-coated filter was dramatically reduced in the presence of the collagenase inhibitor, tissue inhibitor of metalloproteinase-2, suggesting a critical role for MMP-9 in the invasive process. Immunohistochemical studies demonstrating the presence of MMP-9 in tumor cells of resected squamous-cell cancers suggested that secretion of this collagenase by cells in vitro was reflective of the in vivo setting. Since several phorbol-ester response elements are present in the MMP-9 promoter, we determined the role of protein-kinase-C pathways in the regulation of MMP-9 expression in cultured SCC. Treatment of cells with PMA resulted in a more-than-20-fold increase in the level of protein and mRNA. Conversely, culturing of cells in the presence of the protein-kinase-C inhibitor, calphostin-C, led to a dose-dependent decrease in the amount of MMP-9 mRNA and protein, suggesting that the constitutive expression of this collagenase reflects activation of this signal transduction pathway. In summary, our data suggest that, for a sub-population of squamous-cell carcinomas, secreted MMP-9 is an important determinant of the invasive phenotype, and that the expression of this metalloproteinase is regulated by protein-kinase-C pathways.
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PMID:Role and regulation of expression of 92-kDa type-IV collagenase (MMP-9) in 2 invasive squamous-cell-carcinoma cell lines of the oral cavity. 768 50

Mesangial cells are known to secrete metalloproteinases that are capable of degrading the constituents of the GBM, and hence are potentially involved not only in the regular maintenance of the ECM components in the glomerulus, but also of contributing to any damage to these components that occurs in disease states. In this report we positively identify by Northern blotting the neutral proteinase that is constitutively secreted by the human mesangial cell (HMC) as gelatinase A (MMP2). Stimulation of HMC gelatinase by IL-1 beta or PMA causes an increase in the total amount of gelatinolytic activity secreted. On examination, however, this increased activity is shown, both by immunoreactivity and by PCR to be due to the induction of the higher molecular weight form of gelatinase, gelatinase B (MMP9), while the amount of gelatinase A remained unaffected. In addition antigen and messenger RNA have been identified for both the specific inhibitors of metalloproteinases TIMP-1 and TIMP-2. The appearance of the larger inducible gelatinase with similar substrate specificity implies that the regular turnover of matrix components may be due to the constitutively released gelatinase A while in pathological situations the inducible gelatinase B becomes predominant. The synthesis and secretion of TIMP-1 and TIMP-2 indicates that the mesangial cell is capable of controlling the activity of its own secreted enzymes.
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PMID:Identification and independent regulation of human mesangial cell metalloproteinases. 799 10

Neutrophil and monocyte chemotactic factors were isolated from conditioned media of mouse fibroblasts and epithelial cells. Neutrophil chemotactic activities were purified to homogeneity using a four-step chromatographic procedure, and the corresponding proteins were identified by amino acid sequence analysis. Natural forms of the murine chemokines KC and macrophage inflammatory protein-2 were isolated from virus-infected fibroblasts. However, the major neutrophil chemotactic activity from fibroblasts stimulated with endotoxin plus double-stranded RNA and from PMA-treated epithelial cells resided in other 7- and 8-kDa proteins. Amino acid sequence analysis revealed a novel Cys-Xaa-Cys chemokine structure, characterized by the conservation of four cysteines and the Glu-Leu-Arg motif. Based on the completely identified primary structure of this natural protein, this chemokine must be considered to be the murine homologue of human and bovine granulocyte chemotactic protein-2 (GCP-2; 61 and 64% identical residues, respectively). Due to NH2-terminal cleavage, 11 different forms of mouse GCP-2 were discovered. In contrast to human and bovine GCP-2, functional comparison of long and short NH2-terminal forms of mouse GCP-2 demonstrated that truncated mouse GCP-2 (short form) has a higher specific activity in neutrophil activation (gelatinase B release) and chemotaxis assays. Furthermore, mouse GCP-2 was more potent than human GCP-2 on human neutrophils, and more active than murine KC and macrophage inflammatory protein-2 on mouse neutrophils. In view of the absence of a murine homologue for IL-8, NH2-terminally processed GCP-2 can be considered a major neutrophil chemoattractant in the mouse during the inflammatory response.
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PMID:Identification of mouse granulocyte chemotactic protein-2 from fibroblasts and epithelial cells. Functional comparison with natural KC and macrophage inflammatory protein-2. 875 63

Matrix metalloproteinases play an important role in tumor invasion, angiogenesis and inflammatory tissue destruction. The 72-kd gelatinase A is the most widely distributed. Along with the 92-kd gelatinase B, it plays an important role in basement membrane turnover. Gelatinase A is secreted as progelatinase A and, when activated, can cause extracellular matrix destruction. The physiologic mechanism of this activation is not well understood. Based on the importance of endothelial cells in inflammation and cancer, we sought in this study to systematically study the PMA-induced activation of endothelial cell progelatinase A. Using HUVEC, we demonstrated that PMA-induced activation of progelatinase A in these vascular endothelial cells (a) was protein kinase C-dependent as it was blocked by H-7; (b) occurred through cell-mediated events as PMA was unable to activate progelatinase A in a cell-free system and that low dose tissue inhibitor of metalloproteinases-2, but not tissue inhibitor of metalloproteinases-1, totally inhibited PMA-induced activation; (c) was accompanied by an increase in the membrane-type matrix metalloproteinase (MT-MMP). We also found that the combination of PMA and the cytokine tumor necrosis factor-alpha increased HUVEC secretion and activation of gelatinase B. In conclusion, our data show that PMA activation of vascular endothelial cell progelatinase A is a cell membrane event that is at least partially mediated through a PKC-dependent mechanism and is accompanied by an increase synthesis of MT-MMP. These data suggest a role for MT-MMP in the activation of progelatinase A in vascular endothelial cells.
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PMID:Activation of human umbilical vein endothelial cell progelatinase A by phorbol myristate acetate: a protein kinase C-dependent mechanism involving a membrane-type matrix metalloproteinase. 878 Jan 71

Thickening and reduplication of the tubular basement membrane has been reported as an early event in diabetic nephropathy. In the current study we examined the effects of elevated D-glucose concentrations on human proximal tubular (HPTC) type IV collagen and fibronectin turnover. Incubation of confluent growth arrested HPTC with 25 mM D-glucose led to accumulation of both type IV collagen and fibronectin. This effect was maximal at 48 hours and represented a sevenfold increase for fibronectin (N = 4, P = 0.04), and a threefold increase for type IV collagen (N = 3, P = 0.03) over cells exposed to 5 mM D-glucose controls. This increase was not dependent on new gene transcription for either protein. Tissue inhibitor of metalloproteinases (TIMP 1 + TIMP 2) were induced following addition of 25 mM D-glucose, but not when cells were exposed to 5 mM D-glucose. Twenty-four hours after the addition of 25 mM D-glucose there was an eightfold increase in TIMP 1 (P = 0.009, N = 4), and a tenfold increase in TIMP 2 levels (P = 0.003, N = 4), over the control values for both inhibitors. The increase in both TIMP 1 and TIMP 2 in response to 25 mM D-glucose was abrogated in a dose dependent manner by the aldose reductase inhibitor sorbinil. Gelatin-substrate gel zymography showed increased activity of gelatinase A, but not of gelatinase B in response to the addition of 25 mM D-glucose to HPTC. The induction of gelatinase A was accompanied by increased gelatinase A mRNA expression, which was inhibited both by protein kinase C (PKC) depletion using PMA pre-treatment, and by the addition of a PKC inhibitor. These data demonstrate that the glucose-induced accumulation of type IV collagen and fibronectin is unrelated to increased gene transcription, but may involve alterations in the degradative pathway of these basement membrane constituents. Furthermore, the data demonstrate that glucose may simultaneously activate two intracellular pathways (the polyol pathway and a PKC dependent activation pathway), which are involved in mediating separate, complementary effects on cell function.
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PMID:Exposure of human renal proximal tubular cells to glucose leads to accumulation of type IV collagen and fibronectin by decreased degradation. 932 36

We recently developed an immortalized osteoclast (OCL) precursor cell line that forms large numbers of OCLs. This cell line was derived from mice doubly transgenic for bcl-X(L) and large T antigen that was targeted to cells in the OCL lineage (bcl-X(L)/Tag cells). We have now characterized these cells in terms of their surface and enzymatic phenotype, responsiveness to osteotropic factors, and differentiation potential. The bcl-X(L)/Tag cells expressed interleukin-1 receptors 1 and 2, gelatinase B (MMP9), as well as Mac-1, CD16/CD32 (Fcgamma receptors), CD45.2 (common leukocyte marker), CD86 (costimulatory molecule expressed on B cells, follicular dendritic cells, and thymic epithelium), major histocompatibility complex I, and nonspecific esterase when cocultured with MC3T3E1 cells. However, they did not express the antigens for F4/80 (mature macrophage/dendritic cell marker) by immunostaining. Treatment of bcl-X(L)/Tag cells, cocultured with MC3T3E 1 cells, with the combination of 1,25-dihydroxyvitamin D3 and dexamethasone induced high levels of OCL formation. The bcl-X(L)/Tag cells formed large numbers of OCLs when cultured with RANK ligand and macrophage colony-stimulating factor in the absence of feeder cells. In the absence of RANK ligand and a feeder cell layer, 100% of the cells differentiated into F4/80-positive cells. However, neither PTH nor PTH-related protein enhanced OCL formation by bcl-X(L)/Tag cells even when they were cocultured with primary osteoblasts, suggesting that they differ from primary mouse bone marrow cells in their responsiveness to PTH/PTH-related protein. Thus, bcl-X(L)/Tag cells have many of the properties of primary mouse OCL precursors and should be very useful for studies of OCL differentiation and divergence of OCL precursors from the macrophage lineage.
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PMID:Characterization of immortalized osteoclast precursors developed from mice transgenic for both bcl-X(L) and simian virus 40 large T antigen. 1038 86

There is a growing body of evidence that implicates matrix metalloproteinases (MMPs) as major players in numerous diseased conditions. The articular cartilage degradation that is characteristic of rheumatoid arthritis (RA) is believed to be mediated by the collagenase subfamily of matrix metalloproteinases. The preference of collagenase-3 (CL-3) for collagen type II makes it a likely candidate in the turnover of articular cartilage and a potential target for drug development. In this study, RA synovial membrane tissue was shown to express CL-3 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR) and protein by immunohistochemistry. Fibroblasts isolated and cultured from RA synovial membrane tissue were induced to express CL-3 mRNA. CL-3 mRNA was detected after PMA treatment in 16 of the 18 RA synovial membrane fibroblast cell lines established for this study. These fibroblasts also expressed mRNA for collagenase-1 (CL-1, MMP-1), membrane type-1 matrix metalloproteinase, gelatinase A, gelatinase B, stromelysin-1, stromelysin-2, TIMP-1, and TIMP-2. They were further shown to express CL-1 mRNA constitutively and CL-3 mRNA only after stimulation with PMA, IL-1, TGF-beta1, TNF-alpha, or IL-6 with IL-6sR. These fibroblasts also expressed after induction both CL-1 and CL-3 at the protein level as determined by Western blot analyses and immunofluorescence.
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PMID:Induction of collagenase-3 (MMP-13) in rheumatoid arthritis synovial fibroblasts. 1104 Apr 55

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that play crucial roles in proteolytic degradation of the extracellular matrix. Aberrant expression of the 92-kDa type IV collagenase (MMP-9) is implicated in the invasion and angiogenesis process of malignant tumors and in inflammatory diseases of the CNS. We investigated the effects of IFN-gamma and IFN-beta, cytokines used for treating some cancers and multiple sclerosis, on MMP-9 expression in human astroglioma and fibrosarcoma cell lines and primary astrocytes. Our results demonstrate that IFN-gamma and IFN-beta significantly inhibit MMP-9 enzymatic activity and protein expression that is induced by PMA and the cytokine TNF-alpha. The inhibitory effects of IFN-gamma and IFN-beta on MMP-9 expression correlate with decreased steady state MMP-9 mRNA levels and suppression of MMP-9 promoter activity. IFN-gamma- and IFN-beta-mediated inhibition of MMP-9 gene expression is dependent on the transcription factor STAT-1alpha, since IFN-gamma and IFN-beta fail to suppress MMP-9 expression in STAT-1alpha-deficient primary astrocytes and human fibrosarcoma cells. Reconstitution of human STAT-1alpha successfully restores the inhibitory effects of IFN-gamma and IFN-beta on MMP-9 gene expression. Thus, these data demonstrate the critical role of STAT-1alpha in IFN-gamma and IFN-beta suppression of MMP-9 gene expression.
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PMID:Transcriptional suppression of matrix metalloproteinase-9 gene expression by IFN-gamma and IFN-beta: critical role of STAT-1alpha. 1167 27


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