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

The matrix metalloproteinases (MMPs) are a family of enzymes that degrade the extracellular matrix (ECM) and are considered to be important in neoplastic cell invasion and metastasis. Structural changes in the extracellular matrix are necessary for cell migration during tissue remodeling and neoplastic invasion. Expression of MMP-2, -3, -9, -10, and -13 was investigated in human childhood medulloblastomas (MEDs)/primitive neuroectodermal tumors (PNETs) employing an indirect alkaline phosphatase conjugated immunohistochemical antigen detection technique. Evaluation of the results was based on (a) the percent of neoplastically transformed tissue that reacted positively and (b) a measure of immunoreactivity or staining intensity [graded from A (highest) to D (negative)]. Strong overall expression of MMP-3 and -10 was found in MEDs/PNETs, especially in the ECM adjacent to blood vessels. Positive immunoreactivity was identified for these two MMPs in the ECM surrounding over 90% of the neoplastically transformed cells with the staining intensity being also the strongest possible (A,B). These two forms of stromelysin (SL), types 1 (MMP-3) and 2 (MMP-10), share 82% sequence homology, but exhibit differences in cellular synthesis and inducibility by cytokines and growth factors in vitro. Focal (surrounding less than 10% of the neoplastically transformed cells) but strong (A,B) immunoreactivity was determined for collagenase-3 (MMP-13), an endopeptidase characterized by a potent degrading activity against a wide spectrum of substrates. Weak (surrounding anywhere between 10% and 90% of the neoplastically transformed cells, and of B and B,C intensity) expression of MMP-2 (gelatinase A) and MMP-9 (gelatinase B), two cytokine-induced MMPs, was also observed. It is clear that the activation of MMPs and their inhibitors occurs in a very well orchestrated manner. The necessity of these same enzymes for the extravasation and infiltration of lymphocytes into regions of chronic local inflammation, as associated with neoplastically transformed masses of cells, may aid the transformed cells which have already acquired a more aggressive, metastatic immunophenotype (IP) to enter the peripheral circulation. Further characterization of the expression and utilization of MMPs and their inhibitors in the progression of solid human malignancies should lead to the development of novel anti-cancer therapies.
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PMID:Matrix metalloproteinase expression in childhood medulloblastomas/primitive neuroectodermal tumors. 1121 44

The matrix metalloproteinases (MMPs) are a family of enzymes that degrade the extracellular matrix (ECM) and are considered to be important in neoplastic cell invasion and metastasis. Structural changes in the extracellular matrix are necessary for cell migration during tissue remodeling and neoplastic cell invasion. Histochemical expression of MMP-2, -3, -9, -10, and -13 was observed in 19 human colorectal carcinomas (CCs) employing an indirect alkaline phosphatase (AP) conjugated antigen detection technique. Evaluation of the results was based on (a) the percent of neoplastically transformed cells that reacted positively and (b) a measure of staining intensity [graded from A (highest) to D]. The two forms of stromelysin (SL), types 1 (MMP-3) and 2 (MMP-10), share 82% sequence homology, but exhibit differences in cellular synthesis and inducibility by cytokines and growth factors in vitro. Strong overall expression of MMP-3 and -10 was found in all CC cases observed, especially in the ECM adjacent to blood vessels. Positive immunoreactivity could be seen for these two MMPs in the ECM surrounding over 90% of the neoplastically transformed cells, and the staining intensity was also the strongest possible (A,B). Weak (surrounding anywhere between 10% and 90% of the neoplastically transformed cells, and of strong A,B intensity) expression of MMP-2 (gelatinase A) and MMP-9 (gelatinase B), two cytokine-induced MMPs, was also observed in CCs. Expression of collagenase-3 (MMP-13), an endopeptidase characterized by a potent degrading activity against a wide spectrum of substrates, was not defined in the CCs cases observed by us. It is clear that the activation of MMPs and their inhibitors occurs in a very well orchestrated manner. The necessity of these same enzymes for the extravasation and infiltration of lymphocytes into regions of chronic local inflammation, as associated with neoplastically transformed masses of cells, may aid the transformed cells which have already acquired a metastatic immunophenotype to enter the peripheral circulation. Further characterization of the expression and utilization of MMPs and their inhibitors in the progression of solid human neoplasms should lead to the development of novel anti-cancer therapies.
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PMID:Prognostic significance of matrix metalloproteinase expression in colorectal carcinomas. 1121 43

Reperfusion damages the blood-brain barrier (BBB). Matrix metalloproteinases (MMPs) are associated with the opening of the BBB, but their cellular localization and activation mechanisms are uncertain. We used immunohistochemistry to determine the cellular localization of the MMPs in reperfused rat brain, and cell cultures to study their activation. Spontaneously hypertensive rats (SHR) had a 90 min middle cerebral artery occlusion (MCAO) followed by reperfusion for times from 3 h to 21 days. Frozen sections were immunostained with antibodies to gelatinase A (MMP-2), stromelysin-1 (MMP-3), and gelatinase B (MMP-9). Sham-operated control rats showed MMP-2 immunostaining in astrocytic processes next to blood vessels. After 3 h of the onset of reperfusion MMP-2 immunostaining increased in astrocytes. At 24 h immunoreactivity for MMP-3 and MMP-9 appeared. MMP-3 co-localized with activated microglia (Ox-42+) and ischemic neurons (NeuN+). MMP-9 immunostaining was seen at 48 h in endothelial cells, neutrophils, and neurons. At 5 and 21 days intense MMP-2 staining was seen in reactive astrocytes around the ischemic core. Studies of activation of the MMP were done in lipopolysaccharide (LPS)-stimulated astrocyte and microglia cultures. Stimulated astrocytes produced an activated form of MMP-2. When microglia were stimulated, they activated MMP-9. Immunostaining showed MMP-3 in cultures of enriched microglial cells. The hydroxymate-type, MMP inhibitor, BB-1101, blocked the activation of MMP-2 and MMP-9 by LPS in mixed glial cultures. We propose that MMP-2 is normally present in astrocytic end feet, and that during ischemia MMP-9 and MMP-3 are produced. MMP-3 in microglia/macrophages may be activating proMMP-9. Our results show that a differential expression of MMPs by astrocytes, microglia, and endothelial cells at the blood vessels is involved in the proteolytic disruption of the BBB.
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PMID:Immunohistochemistry of matrix metalloproteinases in reperfusion injury to rat brain: activation of MMP-9 linked to stromelysin-1 and microglia in cell cultures. 1122 98

Two diastereomeric furan-2-carbonylamino-3-oxohexahydroindolizino[8,7-b]indole carboxylates, highly constrained analogues of endogenous pyroglutamyl tripeptide inhibitors of snake venom endopeptidases, have been prepared as potential inhibitors of adamalysin II and matrix metalloproteinases. They proved to be inactive against adamalysin II and weak inhibitors of gelatinase A, gelatinase B, stromelysin 1 and human neutrophil collagenase. Evaluation of the mode of binding of the (2R,5S,11bR) isomer in the active site of adamalysin II suggests that the decrease of potency may be due to the reorientation of the acylamino chain in three of the heterocyclic nucleus, to a short contact at the entrance of the S'(1) hydrophobic cleft and to the loss of flexibility of the tetracyclic nucleus in the P'(1), P'(2) region of the inhibitor, which prevents optimal arrangement in the S'(1) specificity subsite.
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PMID:Conformationally constrained analogues of endogenous tripeptide inhibitors of zinc metalloproteinases. 1123 Oct 48

The extracellular matrix metalloproteases (MMPs) secreted by various human tumor cells play a crucial role in tumor cell invasion and metastasis, but their expression in malignant mesothelioma (MM) cells has not been examined. In this study, we have investigated the spectrum of MMPs and tissue inhibitors of metalloproteases (TIMPs) produced by 8 MM cell lines. Using RT-PCR, we found that all investigated MM cell lines expressed genes encoding mRNA for MMP-1 (interstitial collagenase), MMP-2 (gelatinase A), MMP-3 (stromelysin-1), MMP-9 (gelatinase B) and TIMPs 1, 2 and 3. We also found that 6/8 MM cell lines expressed MMP-7 (matrilysin) and 3/8 MM cell lines expressed MMP-10 (stromelysin-2). MMP-11 (stromelysin-3) was not detected in any of the MM cell lines. Production of MMP-2 and MMP-9 was confirmed using gelatin zymography. In addition, all MM cell lines secreted a 66 kDa metalloprotease, while 3/8 MM cell lines secreted 46, 48, 51 and 63 kDa metalloproteases which specifically degraded the extracellular matrix components fibronectin, vitronectin and laminin. The 66 kDa protease was identified as MMP-3 by Western blot. Our results reveal a broad spectrum of MMPs and TIMPs produced by MM cells and indicate that different substrate specificities of MMPs may play a role in MM cell invasion.
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PMID:Expression and activity of matrix metalloproteases in human malignant mesothelioma cell lines. 1126 73

The matrix metalloproteinase (MMP) and fibrinolytic (plasminogen/plasmin) systems cooperate in many (patho)physiological processes requiring extracellular proteolysis. The effect of MMP-3 (stromelysin-1), MMP-7 (matrilysin), MMP-9 (gelatinase B) or MMP-12 (metalloelastase) on cellular fibrinolytic activity was studied with the use of smooth muscle cells (SMC) and fibroblasts derived from mice with specific inactivation of these genes. Activation of cell-bound plasminogen by two-chain urokinase-type plasminogen activator (tcu-PA) was not significantly different with SMC or fibroblasts from the gene-deficient mice (78% to 140% of wild-type). For all cell types, very limited conversion of plasminogen to angiostatin-like kringle-containing fragments was observed (< 3% of the total cell-bound plasminogen). Activation of plasminogen in solution by cell-associated tcu-PA was also comparable for SMC or fibroblasts of the different genotypes (54% to 160% of wild-type). In vitro SMC migration on scrape wounded collagen-coated surfaces was comparable for wild-type, MMP-7(-/-), MMP-9(-/-) and MMP-12(-/-) SMC, but was significantly reduced for MMP-3(-/-) SMC (P < .005 vs. wild-type). Serum-free conditioned medium of MMP-3(-/-) and MMP-7(-/-) SMC or fibroblasts induced similar lysis of fibrin films as wild-type cells. These findings indicate that several interactions that have been described between these MMPs and the plasminogen/plasmin system in a purified system do not significantly affect plasmin-mediated cellular fibrinolytic activity under cell culture conditions.
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PMID:Matrix metalloproteinase deficiencies do not impair cell-associated fibrinolytic activity. 1132 16

Matrix metalloproteinases (MMPs) are upregulated locally in sites of inflammation, including the lung. Several MMP activities are upregulated in acute lung injury models but the exact role that these MMPs play in the development of the lung injury is unclear due to the absence of specific inhibitors. To determine the involvement of individual MMPs in the development of lung injury, mice genetically deficient in gelatinase B (MMP-9) and stromelysin 1 (MMP-3) were acutely injured with immunoglobulin G immune complexes and the intensity of the lung injury was compared with genetically identical wild-type (WT) mice with normal MMP activities. In the WT mice there was upregulation of gelatinase B and stromelysin 1 in the injured lungs which, as expected, was absent in the genetically deficient gelatinase B- and stromelysin 1-deficient mice, respectively. In the deficient mice there was little in the way of compensatory upregulation of other MMPs. The gelatinase B- and the stromelysin 1-deficient mice had less severe lung injury than did the WT controls, suggesting that both MMPs are involved in the pathogenesis of the lung injury. Further, the mechanism of their involvement in the lung injury appears to be different, with the stromelysin 1-deficient mice having a reduction in the numbers of neutrophils recruited into the lung whereas the gelatinase B-deficient mice had the same numbers of lung neutrophils as did the injured WT controls. These studies indicate, first, that both gelatinase B and stromelysin 1 are involved in the development of experimental acute lung injury, and second, that the mechanisms by which these individual MMPs function appear to differ.
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PMID:Role of stromelysin 1 and gelatinase B in experimental acute lung injury. 1135 Aug 22

Women are more susceptible to anterior cruciate ligament (ACL) injuries than men performing similar athletic activities. Because tissue remodeling may affect ligament strength, we assessed expression of tissue remodeling effector genes in the human ACL. Specifically, we surveyed ACL for RNAs encoding all known matrix metalloproteases (MMPs) and tissue inhibitors of metalloproteases (TIMPs) by reverse transcription/polymerase chain reaction (RT-PCR). These experiments revealed that mRNAs encoding nine of sixteen MMPs and all four TIMPs are present in the normal ACL. The nine expressed proteases were MMPs 1-3, 7, 9, 11, 14, and 17 (collagenase 1, gelatinase A, stromelysin 1, matrilysin, gelatinase B, stromelysin 3, and membrane types 1 and 4, respectively), and MMP-18. Genes for MMPs 8, 10, 12, 13, 15, and 16 appeared not to be expressed in ACL, as their mRNAs were not detected using RT-PCR conditions that did yield positive signals from other tissues (testis or bone). We conclude that numerous genes encoding tissue remodeling effector proteins are expressedin the human ACL.
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PMID:Expression of matrix metalloprotease and tissue inhibitor of metalloprotease genes in human anterior cruciate ligament. 1151 74

Platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) and gelatinase B are coexpressed at sites of inflammation, where an intense interaction occurs between leukocytes and endothelial cells. To investigate whether a functional link exists between PECAM-1 activation and gelatinase B production, the regulatory role of PECAM-1, IFN-gamma, IFN-beta, LPS, and PMA on the production of gelatinase B (MMP-9) was studied in vitro in normal human umbilical vein endothelial cells (HUVECs), human peripheral blood mononuclear cells (PBMCs), and in a human monocytic leukemia cell line. In THP-1 cells, progelatinase B levels were slightly up-regulated by immobilized PECAM-1-specific monoclonal antibody (mAb) and soluble recombinant PECAM-1 when compared with strong induction by LPS and PMA. IFN-beta inhibited the induced and basal gelatinase B production but had no modulating effect on the expression of PECAM-1. HUVECs mainly produced progelatinase A (proMMP-2). Treatment with LPS and triggering of the endothelial cells with PECAM-1 mAb or recombinant PECAM-1 had no effect on gelatinase A or B production, whereas PMA stimulated the production of progelatinase B. IFN-beta significantly up-regulated the expression of PECAM-1 in HUVECs but did not affect gelatinase secretion. Finally, in PBMCs, progelatinase B production was increased by soluble PECAM-1 mAb, recombinant PECAM-1, LPS, and PMA, whereas IFN-beta reduced gelatinase B secretion. IFN-beta did not alter PECAM-1 expression on PBMCs. Thus, PECAM-1 and gelatinase B are differently regulated in leukocytes and endothelial cells.
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PMID:Regulation of gelatinase B in human monocytic and endothelial cells by PECAM-1 ligation and its modulation by interferon-beta. 1178 84

Leukocytosis is the result of white blood cell production in the bone marrow, margination onto the blood and lymph vessels and elimination of leukocytes in the peripheral tissues and the spleen. The regulation of the exit of leukocytes from the circulation at peripheral inflammatory sites is well known as the four-step paradigm of rolling, adhesion, diapedesis and chemotaxis. The entry of white blood cells into the circulation is less well studied. In the bone marrow, immature myeloid cells adhere to the stromal network by means of interactions between oligosaccharides and lectins and between adhesion molecules. During the maturation process, cell surface molecules are altered and the possibilities for multivalent binding to stroma components or cells are gradually lost. Mature cells produce matrix metalloproteinases (MMPs) that solubilise the basement membranes of the bone marrow sinuses. Hematogenic signals of inflammation activate mature granulocytes in the bone marrow and cause an increase in the circulating pool of leukocytes. The so-called shift-to-the-left, i.e. the presence of precursor forms of differentiating neutrophils, appears during full blown reactions. In the latter situation, immature cells, positive for the CD34 cell surface marker, enter the circulation. The activities of gelatinase B and integrin interactions are indispensable to induce leukocytosis and stem cell mobilization. Indeed, with the use of neutralizing antibodies against gelatinase B and against lymphocyte-associated functional antigen-1 (LFA-1), experimentally induced leukocytosis and stem cell mobilization were blocked. What is the role of adhesion molecules and proteases in septic shock syndromes? In the early phase of endotoxinaemia or bacteraemia, the bone marrow will be activated, which leads to leukocytosis. Neutrophils secrete considerable amounts of latent MMPs, including neutrophil procollagenase (MMP-8) and progelatinase B (MMP-9). In addition, these granulocytes activate the enzymes chemically and these cells are not able to produce tissue inhibitors of metalloproteinases (TIMPs). As a result, an intensive degradation of endothelial basement membranes occurs and results in vascular leakage and shock. These observations raise the hope that inhibition of proteases might constitute a new strategy for the treatment of septic shock.
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PMID:New insights in the regulation of leukocytosis and the role played by leukocytes in septic shock. 1181 8


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