Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.23 (MMP)
 4,246 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We reported that interstitial collagenase is produced by keratinocytes at the edge of ulcers in pyogenic granuloma, and in this report, we assessed if production of this metalloproteinase is a common feature of the epidermal response in a variety of wounds. In all samples of chronic ulcers, regardless of etiology, and in incision wounds, collagenase mRNA, localized by in situ hybridization, was prominently expressed by basal keratinocytes bordering the sites of active re-epithelialization indicating that collagenolytic activity is a characteristic response of the epidermis to wounding. No expression of mRNAs for 72- and 92-kD gelatinases or matrilysin was seen in keratinocytes, and no signal for any metalloproteinase was detected in normal epidermis. Immunostaining for type IV collagen showed that collagenase-positive keratinocytes were not in contact with an intact basement membrane and, unlike normal keratinocytes, expressed alpha 5 beta 1 receptors. These observations suggest that cell-matrix interactions influence collagenase expression by epidermal cells. Indeed, as determined by ELISA, primary cultures of human keratinocytes grown on basement membrane proteins (Matrigel; Collaborative Research Inc., Bedford, MA) did not express significant levels of collagenase, whereas cells grown on type I collagen produced markedly increased levels. These results suggest that migrating keratinocytes actively involved in re-epithelialization acquire a collagenolytic phenotype upon contact with the dermal matrix.
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PMID:Cell-matrix interactions modulate interstitial collagenase expression by human keratinocytes actively involved in wound healing. 825 40

Matrix metalloproteinases (MMPs) play a role in tissue remodelling and angiogenesis. We have investigated the expression and regulation of MMP-1 (interstitial collagenase), MMP-2 (gelatinase A), MMP-3 (stromelysin 1), MMP-7 (matrilysin), MMP-9 (gelatinase B) and their inhibitors TIMP-1 and TIMP-2 in human umbilical vein, femoral vein and microvascular endothelial cells, and compared these data with those obtained with human synovial fibroblasts. Non-stimulated vein endothelial cells expressed the mRNAs for MMP-1, MMP-2, TIMP-1 and TIMP-2. MMP-3 mRNA and protein were undetectable or only weakly expressed, but could be stimulated by the inflammatory mediator tumour necrosis factor alpha (TNF alpha). The expression of MMP-3 and MMP-1 was further enhanced by phorbol 12-myristate 13-acetate (PMA). Phorbol ester also induced TIMP-1 and MMP-9, the expression of the latter being further enhanced by TNF alpha or interleukin 1 alpha (IL-1 alpha). Similar stimulatory effects were observed in microvascular endothelial cells. Hence the inflammatory mediator TNF alpha induces/enhances the production of several matrix metalloproteinases in human endothelial cells. On the other hand, MMP-2 and TIMP-2 were not affected or were affected in a variable way by TNF alpha and/or phorbol ester, suggesting a dissimilar regulation of these proteins. The cyclic AMP-enhancing agent forskolin affected the production of MMPs in a cell-type-specific way. In human vein endothelial cells it enhanced the PMA-mediated induction of MMP-9, whereas it suppressed this induction in human microvascular endothelial cells and in synovial fibroblasts. On the other hand, forskolin suppressed the PMA-mediated induction of MMP-1 and MMP-3 in synovial fibroblasts, while it enhanced or did not affect this induction in various types of human endothelial cells. These observations may have implications for future pharmacological intervention in angiogenesis.
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PMID:Regulation of matrix metalloproteinase expression in human vein and microvascular endothelial cells. Effects of tumour necrosis factor alpha, interleukin 1 and phorbol ester. 828 80

Matrilysin, a member of the matrix metalloproteinase family, is structurally different from the other matrix metalloproteinases by virtue of the absence of a conserved COOH-terminal protein domain. In addition, matrilysin mRNA is regulated in a specific and distinct manner in normal and malignant tissues. Analysis of the genomic structure of the human matrilysin gene revealed that the organization of the first five exons is highly conserved among the different members of the matrix metalloproteinase family, but that matrilysin contains an atypical sixth exon. The promoter region of the matrilysin gene has several features that are conserved among several other matrix metalloproteinase family members, including the presence of TATA, AP-1, and PEA3 elements. Comparison of the expression of the human matrilysin promoter with rat stromelysin promoter/chloramphenicol acetyltransferase constructs in HeLa cells revealed that constructs containing AP-1 and PEA3 elements respond similarly to epidermal growth factor and tumor promoter (12-O-tetradecanoyl-phorbol-13-acetate) induction, but that the addition of upstream stromelysin sequences results in an increased transcriptional activity not observed with upstream matrilysin sequences. The similarities and differences observed between the promoters of matrilysin and the other metalloproteinases may provide insights into the molecular mechanisms that regulate the expression of this family of enzymes as a whole and the factors that distinguish the expression patterns of individual family members.
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PMID:Structure and expression of the human gene for the matrix metalloproteinase matrilysin. 829 54

Multiple forms of metalloproteinase inhibitors were found in the serum-free conditioned medium of the EJ-1 human bladder carcinoma cell line by reverse zymography assay with gelatinase A as the indicator enzyme. Two novel forms of inhibitor with apparent molecular masses of 18 and 22 kDa on nonreducing SDS-polyacrylamide gel electrophoresis (PAGE), together with tissue inhibitor of metalloproteinases (TIMP) and TIMP-2, were purified from the conditioned medium by a series of chromatographic steps. Structural analysis showed that the 18-kDa inhibitor is a two-chain form of TIMP-2 (tc-TIMP-2) produced by proteolytic processing, and the 22-kDa inhibitor may be a partially glycosylated form of TIMP. The purified tc-TIMP-2 was separated into a 17-kDa peptide and a small peptide of about 2.5 kDa by reducing SDS-PAGE and into four isoforms with pI 7.6, 7.3, 7.2, and 6.8 by isoelectric focusing. tc-TIMP-2 has essentially the same inhibitory activity as TIMP-2 toward gelatinase A, collagenase, stromelysin, and matrilysin. Unlike TIMP-2, however, tc-TIMP-2 does not bind to the latent precursor fo gelatinase A. Similar two-chain forms of TIMP-2 were produced by its partial digestion with trypsin or less effectively with plasmin. These results suggest that proteolytic processing of TIMP-2 plays a role in the regulation of gelatinase A activity in the extracellular matrix.
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PMID:Purification and characterization of a two-chain form of tissue inhibitor of metalloproteinases (TIMP) type 2 and a low molecular weight TIMP-like protein. 831 98

Entactin is the basement membrane protein which bridges laminin and type IV collagen. Entactin is known to be degraded by serine proteinases, but its susceptibility to matrix metalloproteinases has not been determined. We have studied the capacity of three matrix metalloproteinases (interstitial collagenase, 92-kDa gelatinase, and matrilysin) to degrade entactin. While all three metalloenzymes cleaved entactin, matrilysin was approximately 100-fold as effective as collagenase and 600-fold as effective as 92-kDa gelatinase. The Km of matrilysin for entactin was 8.9 x 10(-7) M. A Vmax of 21 molecules of entactin degraded/molecule of matrilysin/min at 37 degrees C was observed. An Arrhenius plot relating matrilysin's catalytic activity to temperature was linear from 15 to 37 degrees C and indicated an activation energy of 10,060 calories/mol. Matrilysin produced multiple, but distinct, cleavages in entactin resulting in peptide fragments ranging from 115 to 29 kDa. The precise sites of cleavage of six fragments were determined by Edman degradation. Cleavage sites consistently occurred amino-terminal to leucine or isoleucine. These data indicate that entactin is a substrate for matrix metalloproteinases. The effectiveness of matrilysin is noteworthy, however, particularly in relation to the minimal ability of other much more well described matrix metalloproteinases to attack this substrate. Our results suggest a potentially important role for matrilysin in disruption of basement membranes by tumor or inflammatory cells.
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PMID:Degradation of entactin by matrix metalloproteinases. Susceptibility to matrilysin and identification of cleavage sites. 838 May 88

The sequence specificities of human 72-kDa fibroblast gelatinase (type IV collagenase), human 92-kDa neutrophil gelatinase (type IV collagenase), and putative metalloproteinase (PUMP or matrilysin) have been examined by measuring the rate of hydrolysis of over 50 synthetic oligopeptides covering the P4 through P4' subsites of the substrate. The peptides investigated in this paper were those employed in our previous study which systematically examined the sequence specificity of human fibroblast and neutrophil collagenases [Netzel-Arnett et al. (1991) J. Biol. Chem. 266, 6747]. The initial rate of hydrolysis of the P1-P1' bond of each peptide has been measured under first-order conditions ([S0] << KM), and kcat/KM values have been calculated from the initial rates. The specificities of these five metalloproteinases are similar, but distinct, with the largest differences occurring at subsites P1, P1', and P3'. The specificities of the two gelatinases are the most similar to each other. They tolerate only small amino acids such as Gly and Ala in subsite P1. In contrast, larger residues such as Met, Pro, Gln, and Glu are also accommodated well by PUMP. All five enzymes prefer hydrophobic, aliphatic residues in subsite P1'. PUMP exhibits a stronger preference for Leu in this subsite than is shown by the other enzymes. The P3' subsite specificities of the gelatinases and collagenases are very similar but different from those of PUMP which particularly prefers Met in this position. The specificity data from this study allow the design of optimized substrates and selective inhibitors for these metalloproteinases.
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PMID:Comparative sequence specificities of human 72- and 92-kDa gelatinases (type IV collagenases) and PUMP (matrilysin). 839 Aug 57

Human prostate cancer displays a high degree of variability in its rate of spread, which could be due largely to differences in the invasive potential of the tumor cells. The degradation of the basal lamina and stromal extracellular matrix is mediated in part by the secretion of matrix metalloproteinases (MMPs). Matrilysin (PUMP-1, MMP-7) and gelatinase A (M(r) 72,000 type IV collagenase, MMP-2) have been shown to be overexpressed in prostate carcinoma. We have expressed the single MMP matrilysin in the tumorigenic but nonmetastatic human prostate tumor cell line DU-145 to determine if matrilysin has a functional role in prostate tumor cell invasion. DU-145 cells expressing matrilysin were significantly more invasive than vector-only transfected cell lines as assayed by a severe combined immunodeficient mouse model of tumor cell invasion. Vector-only transfected DU-145 cells injected i.p. into severe combined immunodeficient mice invaded the diaphragm in only 1 of 9 mice (11%), whereas matrilysin-transfected DU-145 cells invaded the diaphragm in 12 of 18 mice (66%). The difference between the controls and matrilysin-transfected cells was statistically significant (P < 0.006). These results suggest a functional role for matrilysin in the initial invasion of prostate cancer through the epithelial basal lamina and into the surrounding stroma.
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PMID:Expression of the metalloproteinase matrilysin in DU-145 cells increases their invasive potential in severe combined immunodeficient mice. 841 33

Production of matrilysin and stromelysin by five human glioma cell lines was investigated by Northern blot and immunoblot analyses. Four cell lines constitutively produced matrilysin. Its production was stimulated by phorbol-12-myristate-13-acetate (PMA) in two cell lines and by transforming growth factor-beta 1 (TGF-beta 1) in two other cell lines. Stromelysin transcript was constitutively expressed in only two cell lines, but enhanced or induced by PMA in four cell lines. These results suggest that these enzymes, especially matrilysin, may be involved in the invasive growth of neoplastic glial cells.
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PMID:Expressions of matrilysin and stromelysin in human glioma cells. 850 12

The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metalloproteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells.
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PMID:Expression of matrix metalloproteinase matrilysin (MMP-7) was induced by activated Ki-ras via AP-1 activation in SW1417 colon cancer cells. 853 Oct 10

The metalloproteinases, a multigene family of metal-requiring enzymes, have been suggested to play a role in tumor invasion and metastasis. Previously, we demonstrated that human primary prostate tumors express higher levels of matrilysin and gelatinase A mRNA than normal prostate does. In the study presented here, we used in situ hybridization and immunohistochemical staining of serial sections of paraffin-embedded primary prostate tumors to compare the sites of matrilysin and gelatinase A expression and protein localization. These results confirmed the epithelial nature of matrilysin expression and protein localization. In contrast, gelatinase A mRNA was localized to the interstitial stroma, whereas the protein was associated with the epithelial tumor cells. In situ hybridization was also used to demonstrate that gelatinase B expression was restricted to macrophages infiltrating the tumors. Proteins isolated from an additional set of frozen tumor specimens were analyzed by western blotting to determine the relative amounts of matrilysin in the active and proenzyme forms. The western analyses demonstrated that in all cases in which matrilysin was detected, at least some of the enzyme was in the active form. These results are discussed with respect to the possible role these enzymes may play in prostate tumor progression.
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PMID:Matrilysin expression in human prostate carcinoma. 856 67


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