Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.17 (MMP-3)
 3,419 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Malignant tumors are generally characterized by extensive local tissue invasion and destruction of ECM which may be due to increased constitutive expression and activity of secreted proteases. Moreover, a large number of diverse protease activities may be constitutively over-expressed in a simultaneous or co-ordinated fashion, thereby significantly increasing cellular invasive potential of the cells. To explore this relationship, we have measured steady-state levels of mRNA coding for urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), transin and tissue-specific inhibitor of metalloproteinases (TIMP); as well as gelatinolytic, caseinolytic and plasminogen activator activities secreted by SPI, a non-metastatic mouse mammary carcinoma cell line and 4 metastatic sublines derived from it. mRNA encoding metalloproteinase transin was increased 15- to 20-fold, while TIMP transcripts were decreased 3-fold in the metastatic sublines compared to parental SPI tumor cells. Metastatic sublines secreted higher levels of gelatinase (i.e., 92 kDa and 64 kDa) as well as proteases with caseinolytic activity (i.e., 115 kDa and 57 kDa) when compared with SPI cells. Moreover, these enzymes were identified as neutral metalloproteinases. Although the amount of uPA mRNA appeared to be the same in SPI and the metastatic sublines, the latter secreted 1.5-3 times more uPA activity into the culture supernatants. Metastatic competence in the SPI tumor model is therefore associated with increased secretion of several metalloproteinase activities and uPA, as well as decreased TIMP expression, consistent with a more invasive phenotype.
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PMID:Constitutive expression and secretion of proteases in non-metastatic SP1 mammary carcinoma cells and its metastatic sublines. 204

Extracellular matrix metalloproteases are secreted by the resident cells of the tissue in a proenzyme form, and their extracellular activity is regulated at the level of gene expression, proenzyme activation, and interaction with inhibitors. To understand the molecular mechanisms that control the activity of ECM metalloproteases and their effect on the cellular phenotype, we have established cell lines in which the transcription of the protease genes is repressed. We also have undertaken a detailed study of the pathway of extracellular activation of interstitial procollagenase. Stable transfection of three human tumor cell lines--H-ras-transformed bronchial epithelial cells TBE-1, fibrosarcoma cells HT1080, and melanoma cells A2058--with the adenovirus E1A gene dramatically repressed the expression of the secreted proteases, type IV and interstitial collagenases, and urokinase-type plasminogen activator. Concomitantly, E1A-expressing cells showed reduced metastatic activity in vivo and reduced ability to traverse a reconstituted basement membrane in vitro. Monospecific anti-type IV collagenase antibody inhibited the invasive activity of parental tumor cell lines in the in vitro system, suggesting a possible causal relationship between the effect of E1A on the expression of secreted proteases and the reduced metastatic potential of the E1A-expressing transformants. We have also studied the mechanism of regulation of metalloprotease activity at the level of extracellular activation by investigating the cascade of proteolytic events that results in the activation of interstitial procollagenase. Cocultivation of the major cellular components of skin, dermal fibroblasts, and epidermal keratinocytes induces activation of interstitial procollagenase and prostromelysin in the presence of plasminogen. This activation occurs through a uPA-plasmin-dependent pathway in which plasmin catalyzes the first step in activation of both collagenase and stromelysin by amino-terminal processing. Activated stromelysin can in turn convert plasmin-activated collagenase into a fully active enzyme by removal of approximately 15 amino acid residues from the carboxyl end of the enzyme. This second step of activation results in a 5-8-fold further increase in specific activity of collagenase. This cascade of proteolytic events may constitute a major physiologic pathway of collagenase activation.
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PMID:Secreted proteases. Regulation of their activity and their possible role in metastasis. 215 52

The matrix-degrading metalloproteinases stromelysin-1, stromelysin-3, and gelatinase A are expressed during ductal branching morphogenesis of the murine mammary gland. Stromelysin-1 expression in particular correlates with ductal elongation, and in situ hybridization and three-dimensional reconstruction studies revealed that stromelysin-1 mRNA was concentrated in stromal fibroblasts along the length of advancing ducts. Transgenic mice expressing an activated form of stromelysin-1 under the control of the MMTV promoter/enhancer exhibited inappropriate alveolar development in virgin females. Ultrastructural analysis demonstrated that the basement membrane underlying epithelial and myoepithelial cells was amorphous and discontinuous compared with the highly ordered basal lamina in control mammary glands. Transgenic mammary glands had at least a twofold increase in the number of cells/unit area and a 1.4-fold increase in the percent of cycling cells by 13 wk of age compared with nontransgenic littermates. In addition, transgenic glands expressed beta-casein mRNA, but not protein, and resembled the proliferative and differentiated state of an animal between 8 and 10 days pregnant. An analysis of metalloproteinase expression in the glands of normal pregnant females demonstrated that the same matrix metalloproteinase family members, including stromelysin-1, were expressed in connective tissue cells surrounding epithelial clusters during the time of lobuloalveolar development. These results suggest that metalloproteinases may assist in remodeling ECM during normal ductal and alveolar branching morphogenesis, and that disruption of the basement membrane by an activated metalloproteinase can affect basic cellular processes of proliferation and differentiation.
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PMID:Matrix metalloproteinases are expressed during ductal and alveolar mammary morphogenesis, and misregulation of stromelysin-1 in transgenic mice induces unscheduled alveolar development. 857 87

Prior studies using rat primary hippocampal cultures indicated induction of matrix metalloproteinases (MMPs) in response to beta-amyloid (A beta). Hence, it was of interest to determine whether MMP activity in a human cell line is influenced by A beta. A beta, but not interleukin-1beta (IL-1beta) or lipopolysaccharide (LPS), stimulated an active form of MMP-2 in human U87 glioblastoma cells, as well as increased the expression of the well-known activator of MMP-2, membrane-type (MT)-MMP. Activation experiments carried out with amino phenyl mercuric acetate (APMA), immunoprecipitation, as well as immunoblotting, suggest that the lower molecular weight, gelatin-degrading activity was an activated form of MMP-2. Furthermore, it was demonstrated that a synthetic furin convertase inhibitor, decanoyl-Arg-Val-Lys-Arg-chloromethylketone, decreased the production of A beta-induced active MMP-2 in U87 cells. The induction of MMP-3 by cytokines, but not by A beta, suggests that the effect of A beta on MMP-2 is selective. Although A beta stimulated tissue inhibitor of metalloproteinase-1 (TIMP-1), there was no obvious effect of A beta on TIMP-2 production in U87 cells. These results demonstrate that A beta induces an active form of MMP-2 likely by increasing the expression of MT-MMP in a human glioblastoma cell line. Active MMP-2 may degrade A beta or act on ECM components critical in neuronal survival mechanisms and possibly play a role in Alzheimer's disease (AD) neuropathology.
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PMID:Activated isoforms of MMP-2 are induced in U87 human glioma cells in response to beta-amyloid peptide. 989 Apr 33

The aim of the study was to assess the differential intra- and intertumoral heterogeneity and patterns of matrix metalloproteinase expression in human glioblastomas in vivo. 12 glioblastoma samples were analyzed for MMP expression by semi-quantitative RT-PCR. A total of 56 samples (8 adjoining regions of 6 glioblastoma tumors) were immunohistochemically examined for the expression and regional distribution of gelatinase-A (MMP-2), gelatinase-B (MMP-9), matrilysin (MMP-7) and stromelysin-1 (MMP-3). Gelatinase-A mRNA was detected in all samples, gelatinase-B was found in numerous samples. Correspondingly, strong expression levels of both gelatinase protein was seen in immunohistochemistry. Gelatinase-A was expressed by both tumor cells and endothelium while gelatinase-B was found to be restricted to endothelial cells. Stromelysin-1 protein was not detected in any of the samples. Matrilysin was found around tumor cells of three samples from one patient only. The strong immunoreactivity seen for gelatinase-A around tumor cells and blood vessels suggests a role in both tissue degradation and tumor neoangiogenesis which is in accordance with previously published in vitro data. The marked localization of gelatinase-B to the endothelium and its presence in non-infiltrative benign lesions, however, makes a direct proteolytic role of gelatinase-B on ECM components during glioma invasion appear unlikely. Its close association with vascular structures, however, might indicate a link to neoangiogenesis. The significance of matrilysin which was only seen in tumor cells in three samples remains unclear. Stromelysin-1, though strongly expressed in cell lines, does not appear to play a role in glioblastoma tumors in vivo.
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PMID:Heterogeneous regional expression patterns of matrix metalloproteinases in human malignant gliomas. 1057 6

We have recently identified the fifth member of the membrane-type matrix metalloproteinase subfamily, MT5-MMP/MMP24, which is expressed in a brain specific manner (Duanqing Pei (1999) J. Biol. Chem. 274, 8925-8932). To further characterize its enzymic properties, an expression construct was engineered to produce MT5-MMP as a soluble and active form by truncating its transmembrane domain. Stable expression cell lines were subsequently established from MDCK cells transfected with this construct. Unfortunately, purification of MT5-MMP from the culture media in large quantity proves to be difficult initially due to its rapid turnover via a mechanism which can be inhibited by a broad spectrum metalloproteinase inhibitor, BB94. Thus, BB94 was included in the cell culture medium and throughout the purification process except the final step of chromatography to protect MT5-MMP from destruction. Purified to homogeneity and free of the synthetic inhibitor, MT5-MMP can activate progelatinase A efficiently in a TIMP2 sensitive fashion. A preliminary screen for its potential substrates among extracellular matrix components identified the proteoglycans as the preferred substrates for MT5-MMP. Furthermore, it is determined that the stability of purified MT5-MMP is temperature dependent with rapid destruction at 37 degrees C, but being relatively stable at temperatures 4 degrees C or lower. These observations establish MT5-MMP as a proteoglycanase with a short half-life at body temperature, which may be critical for tightly controlled turnover of ECM components such as those in the brain.
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PMID:Expression, purification and characterization of recombinant mouse MT5-MMP protein products. 1062 8

The TIMP family of matrix metalloproteinase inhibitors consists of four members, of which TIMP-1, -2 and -4 are secreted, freely diffusible proteins, whereas TIMP-3 is ECM-associated. Mutations in the TIMP3 gene have been linked to Sorsby's fundus dystrophy (SFD), an autosomal dominant inherited retinal degenerative disease that leads to blindness. The SFD mutations characterized result in introduction of an unpaired cysteine residue in the C-terminal domain of TIMP-3. We have expressed four SFD mutant TIMP-3 proteins in baby hamster kidney (BHK) cells and evaluated their characteristics alongside wild-type TIMP-3. Analysis of the mutant proteins (Ser156Cys, Gly167Cys, Tyr168Cys and Ser181Cys) by SDS-PAGE and reverse zymography revealed that each of the mutants retained gelatinase A and gelatinase B inhibitory activity, and were localized to the ECM. Association rate constants for Ser156Cys TIMP-3 with gelatinase-A, gelatinase-B, stromelysin-1 and collagenase-3 were only moderately reduced compared to wild-type TIMP-3. However, all of the mutants displayed aberrant protein-protein interactions, resulting in the presence of additional proteins or complexes in ECM preparations. Two of the mutants (Ser156Cys and Ser181Cys) showed a marked propensity to form multiple higher molecular-weight complexes that retained TIMP activity on reverse zymography. Expression of the SFD mutant TIMP-3 (and to a lesser extent, wild-type TIMP-3) proteins in BHK cells conferred increased cell adhesiveness to the ECM. Our findings indicate that the pathogenesis of Sorsby's fundus dystrophy cannot be attributed to a failure to localize SFD TIMP-3 proteins to the ECM or defects in MMP inhibition, but may involve the formation of aberrant TIMP-3-containing protein complexes and altered cell adhesion.
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PMID:Sorsby's fundus dystrophy tissue inhibitor of metalloproteinases-3 (TIMP-3) mutants have unimpaired matrix metalloproteinase inhibitory activities, but affect cell adhesion to the extracellular matrix. 1182 95

We surveyed the expression of 557 cancer-related genes in 15 cases of well-differentiated OSCC by cDNA microarray analysis. To identify potential biomarkers for lymph node metastasis, all microarray data were compared by the Mann-Whitney test and the significance analysis of microarrays between OSCCs with and those without lymph node metastasis. The tissues of OSCCs with lymph node metastasis exhibited increased expression levels of MMP-1, MMP-3, uPA, integrin-alpha3, paxillin, tenascin C and IL-6 transcripts. All of these genes were included in common clusters on the Cluster/TreeView analysis, implying that functional gene groups of proteolytic enzymes and integrin-related molecules are involved in cervical lymph node metastasis. The results of RTQ-PCR for differentially expressed genes were in accord with those of cDNA microarray analyses, suggesting that the data obtained by microarray gene expression analyses were valid. Consistent with cooperative expression patterns, immunohistochemical analyses demonstrated that products of MMP-1, MMP-3 and uPA were colocalized to components of the neoplastic stroma, particularly mononuclear inflammatory cells with well-developed eosinophilic cytoplasm. Our results suggest that expression levels of molecules involved in tissue remodeling and cell-ECM adhesion, especially MMP-1 and integrin-alpha3, can provide an accurate biomarker system for predicting the risk of cervical lymph node metastasis in OSCC.
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PMID:Identification of potential biomarkers of lymph node metastasis in oral squamous cell carcinoma by cDNA microarray analysis. 1286 27

In the present study, we found collagenolytic and gelatinolytic activity in the supernatants of hepatocyte cultures from rats with experimental CCl(4)-induced liver cirrhosis, in levels significantly higher than in comparable supernatants of hepatocyte cultures from normal rats. In addition, we clearly detected the messenger ribonucleic acids (mRNA) of four matrix metalloproteinases (MMP-2, MMP-3, MMP-10, and MMP-13) and of two tissue inhibitors of matrix metalloproteinases (TIMP-1 and TIMP-2) in hepatocytes from both normal and cirrhotic rats by RT-PCR and by in situ hybridization. Finally, we demonstrated MMP-2, MMP-3, and MMP-13 and TIMP-1 and TIMP-2 proteins in the same hepatocyte preparations by immunostaining. We conclude that rat hepatocytes produce the major enzymes and inhibitors involved in liver ECM modulation and therefore suggests that they might participate actively in the pathophysiology of liver cirrhosis in rats.
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PMID:Hepatocyte production of modulators of extracellular liver matrix in normal and cirrhotic rat liver. 1633 68

Recent studies have shown that integrins act as mechanoreceptors in articular cartilage. In this study, we examined the effect of blocking RGD-dependent integrins on both ECM gene expression and ECM protein synthesis. Chondrocytes were isolated from full-depth porcine articular cartilage and seeded in 3% agarose constructs. These constructs were loaded in compression with 15% strain at 0.33 and 1 Hz for 12h, in the presence or absence of GRGDSP, which blocks RGD-dependent integrin receptors. The levels of mRNA for aggrecan, collagen II and MMP-3 were determined by semi-quantitative PCR at several time points up to 24h post-stimulation. DNA and sGAG content were determined at several time points up to 28 days post-stimulation. At 0.33 Hz, the mRNA levels for aggrecan and MMP-3 were increased after loading, but the mRNA levels for collagen II remained unchanged. Incubation with GRGDSP counteracted these effects. Loading at 1 Hz led to increased mRNA levels for all three molecules directly after loading and these effects were counteracted by incubation with GRGDSP. The constructs that were loaded at 0.33 Hz showed a lower amount of sGAG, compared to the unstrained control. In contrast, loading at 1 Hz caused an increase in sGAG deposition over the culture period. Blocking integrins had only a counteracting effect on the long-term biosynthetic response of constructs that were compressed at 1 Hz. The results confirmed the role of RGD-dependent integrins as mechanotransducers in the regulation of both ECM gene expression and matrix biosynthesis for chondrocytes seeded in agarose under the applied loading regime. Interestingly, this role seems to be dependent on the applied loading frequency.
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PMID:RGD-dependent integrins are mechanotransducers in dynamically compressed tissue-engineered cartilage constructs. 1965 15


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