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

Substantial evidence indicates that proteolytic degradation of the extracellular matrix is necessary for invasion and metastasis by cancer cells. Our previous work has demonstrated elevated secretion by cultured ovarian adenocarcinoma cells of two gelatinolytic metalloproteinases, a 72-kDa enzyme resembling matrix metalloproteinase 2 (MMP-2) and a 92-kDa enzyme resembling MMP-9 (Moser et al, Int. J. Cancer 56, 552-559, 1994). To assess the potential in vivo relevance of these enzymes, we have examined ovarian carcinoma ascites using gelatin substrate zymography. MMP species identical to those secreted from several well-characterized ovarian adenocarcinoma cell lines were found in the majority of ascites: MMP-2-like gelatinase (23 of 23 cases) and MMP-9-like gelatinase (18 of 23 cases), suggesting a prevalence of these species in the ovarian carcinoma microenvironment and their availability for tumor-associated proteolysis. The contribution of these proteinases to ovarian cancer invasion was further demonstrated by experiments measuring tumor cell-mediated proteolysis of native endothelial cell extracellular matrix (ECM) and tumor cell invasion of reconstituted basement membrane (Matrigel). These data showed that secretion of type IV collagenase activity by a series of independently isolated ovarian adenocarcinoma cell lines correlated well with the ability of these cells to proteolyze the ECM and invade the basement membrane. Furthermore, we have identified and characterized an ovarian carcinoma-associated gelatinase, the 72-kDa MMP found in conditioned media of the DOV 13 cell line, as MMP-2. This enzyme was identical to the previously described MMP-2 from other sources by Western blot, amino terminal sequence, and substrate specificity. Additionally, a large portion of the MMP-2 activity found in DOV 13 conditioned media is active without organomercurial treatment, suggesting that ovarian cancer cells have an endogenous activator of the zymogen. Together, these data suggest that ECM proteolysis mediated by tumor-associated proteinases plays an important role in the invasion and/or metastasis of ovarian carcinoma.
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PMID:Characterization of gelatinases linked to extracellular matrix invasion in ovarian adenocarcinoma: purification of matrix metalloproteinase 2. 869 Feb 99

Malignant human melanoma cells produce many matrix-degrading enzymes, including plasminogen activators and matrix metalloproteinases. These enzymes have substrate specificity for different components of ECM and most of them have been demonstrated to contribute to melanoma cell-mediated dissolution of matrices and to melanoma cell invasion. The degradation of complex matrices in vitro requires the cooperation of proteases with specificity for glycoproteins and collagens. The contribution of proteases to spontaneous melanoma metastasis was studied by overexpressing specific protease inhibitors in human melanoma cells. Overexpression of PAI-2 inhibited the spread of distant metastasis indicating a role for uPA/plasmin in melanoma invasion. Overexpression of TIMP-2, in contrast, reduced the growth rate of subcutaneous tumors, but did not inhibit metastasis, indicating that MMP activities promote melanoma growth in the skin and may not be required for metastatic dissemination. Thus, uPA and MMP activities are involved in different processes, but they both contribute to melanoma malignancy.
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PMID:Different roles for plasminogen activators and metalloproteinases in melanoma metastasis. 881 95

Tissue inhibitor of metalloproteinases-3(TIMP-3), a novel member of TIMP family genes, has been recently cloned and shown to be expressed in preneoplastic but not in neoplastic mouse JB6 epidermal cells (Sun et al. 1994 Cancer Res., 54, 11139). This down regulation of the gene appears to be attributable at least in part to alteration of gene methylation (Sun et al. 1995 J. Biol. Chem., 270, 19312). Little is known, however, about the role of TIMP-3 in human cancers. We screened several human tumor cell lines for TIMP-3 expression and found that a colon carcinoma line, DLD-1, did not express TIMP-3. If down regulation of TIMP-3 is causally related to carcinogenesis, re-expression by transfection may reverse the tumor cell phenotype. We therefore overexpressed human TIMP-3 in DLD-1 cells. TIMP-3 transfectants showed a serum-dependent growth inhibition in monolayer culture and a decreased growth potential in nude mice in a manner dependent on the level of TIMP-3 expression. A transfectant expressing a high level of active hTIMP-3 completely lost the ability to form tumors following s.c. injection into nude mice. We also tested TIMP-3 expressing cells and neocontrol TIMP-3 negative cells for their ability to grow in liquid suspension culture, since both cells grew in semi-solid soft agar. As compared to neocontrol cells, TIMP-3 overexpressors formed large aggregates, followed by cell death. This effect was not mimicked by BB94, a broad MMP inhibitor. We conclude from this study that (i) TIMP-3 overexpression in human colon carcinoma cells induces growth arrest in low serum conditions and inhibits in vivo tumor growth and (ii) the TIMP-3-induced large aggregate formation and subsequent cell death under suspension growth cannot be explained by its MMP inhibitory activity.
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PMID:Suppression of in vivo tumor growth and induction of suspension cell death by tissue inhibitor of metalloproteinases (TIMP)-3. 882 99

In sarcoidosis, pleomorphic chromogens (PCs) occur as multivariate pigmented elements within sinusoids of lymph nodes (sinusoidal phase) and as tiny "round bodies" detectable in granulomas (generalized phase). The sinusoidal phase occurs in other conditions as well and characteristically contains yeastlike bodies also known as H-W bodies. To elucidate the antigenic profile of all variant forms, 28 cases of sarcoidosis (series A) and 14 cases of malignancy associated sinus histiocytosis (series B) were studied immunohistochemically with panels of various antibodies, including antimycobacterial MAbs specific for M tuberculosis complex (TB68, TB71), for M. leprae (MMP-I-3C3) and for cross-reactive mycobacterial antigens (F24-2-3 and F116-5, the latter recognizing superoxide dismutase). Results for series A indicate that: 1) PCs are cell-wall-deficient (CWD) mycobacterial forms belonging to M. tuberculosis complex (over 95%); 2) both phases are antigenically identical parts of the L-cycle; 3) "round bodies" of the "infective" phase have an endolysosomal evolution; 4)uncommon vacuolated forms represent a labile spheroplast stage; 5) the yeastlike bodies are specialized sinusoidal large bodies of unknown function. Results for series B show that in roughly two thirds of cases the pigmented forms are also CWD mycobacteria, have the same immunophenotype as sarcoid PCs in 35.7% of cases, have a much higher incidence of labile vacuolated forms and, finally, that malignancy associated "pseudosarcoid" granulomas do not differ antigenically from genuine sarcoid granulomas. Unlike conventional mycobacteria, PCs do not express cytoskeletal proteins consistently. Their general reactivity for HBcAg raises the possibility of phage interactions being responsible for the L-cycle since it may reflect shared epitopes between unrelated virus entities.
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PMID:Immunolocalization of cell-wall-deficient forms of Mycobacterium tuberculosis complex in sarcoidosis and in sinus histiocytosis of lymph nodes draining carcinoma. 883 59

Previous immunolabeling studies have indicated that increased expression of the matrix metalloproteinase-2 (MMP-2) zymogen is associated with an increased Gleason score for human prostate cancer. In the accompanying paper, we have found by immunoblotting and ELISA that the MMP-2 enzyme (termed MMP-2a) is expressed in prostate cancer and that increased expression is associated with progression. Monoclonal antibodies specific for MMP-2a were used to investigate the expression of MMP-2a in human prostate tissue sections of benign and malignant cancers. Immunohistochemistry indicated that MMP-2a expression was undetectable in fetal (n = 4), benign (n = 11), and low Gleason score 4 (n = 8) tissue. MMP-2a was faintly expressed (+) in cancer assigned Gleason scores 5 (n = 20) and 6 (n = 13). In comparison, MMP-2a was expressed at an intermediate level (++) in tissues of Gleason score 7 (n = 24), and at a intense level ( to +) in tissues of score 8 (n = 48), 9 (n = 9) and 10 (n = 35) and in lymph node metastases (n = 10). These observations were confirmed by quantitative Computer Assisted Imaging Analysis. In general, MMP-2a was primarily expressed by the glandular epithelial cells, and in high Gleason score 10 specimens (n = 25/35) there was clear evidence of MMP-2a localization at the cell surface. These data suggest that increased MMP-2a expression may be associated with malignant progression and metastases.
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PMID:Immunohistochemical studies of activated matrix metalloproteinase-2 (MMP-2a)expression in human prostate cancer. 885 76

We have examined the expression of 2 tumor-associated metalloproteinases, MMP-2 and MMP-9, in 48 primary cultures of prostatic carcinoma (PRCA) and 33 cultures of benign prostatic hyperplasia (BPH). PRCA cultures secrete significantly more MMP-9 than their benign counterparts. Secreted MMP-2 did not differ significantly in cultures but was lower in PRCA cultures. Two cultures of benign origin exhibited high MMP-9 secretion and growth patterns consistent with a malignancy. Both cases were followed and successively re-evaluated histologically and rediagnosed as organ-confined PRCA. MMP expression in culture may be of predictive value in the identification of incidental PRCA. MMP-9 secretion and its ratio with MMP-2 were highest in epithelial cultures from invasive, metastatic tumors when compared both to disease confined to prostate gland and to locally extensive disease. MMP-9 secretion was greatest also in cultures derived from tissues of high Gleason histological grade. Active MMP-9 species were detected in 15 cultures (31%) of PRCA. Active MMP-2 species were observed in cultures of both BPH and PRCA origin in almost the same amounts. Although average levels were not significantly different, as a ratio to proform species, a significant elevation was observed in cultures of PRCA origin. We propose, therefore, that an elevated expression of MMP-9 and a high ratio of MMP-9 to MMP-2 in short-term prostate epithelial cultures is of potential diagnostic and prognostic significance.
Int J Cancer 1996 Oct 21
PMID:Increased matrix metalloproteinase-9 secretion in short-term tissue cultures of prostatic tumor cells. 890 Mar 72

Matrilysin and gelatinase A, B mRNA expressions were examined in colorectal tumors. Matrilysin mRNA was observed exclusively in tumors, while the others were also found in normal mucosa surrounding tumors. Further analysis revealed that colorectal adenomas with severe dysplasia, not with mild dysplasia, expressed matrilysin with lower levels than cancers. The level of matrilysin mRNA expression increased with the advancement of stages of colorectal cancers, consequently a relatively higher expression was observed in liver metastatic tumors than primary tumors. These results suggest that matrilysin mRNA expression was correlated with the progression of colorectal tumors, and this enzyme may also play a role in developing metastatic tumors in liver.
Cancer Lett 1996 Oct 01
PMID:Matrilysin is associated with progression of colorectal tumor. 891 60

Membrane-type metalloproteinase-I (MTI-MMP) is a transmembrane metalloproteinase, which activates pro-gelatinase A. There has been disagreement as to whether the cell types expressing MTI-MMP are cancer cells or stromal fibroblasts. Using human gastrointestinal carcinomas, the present study disclosed the tissue localization of MTI-MMP mRNA by in situ hybridization and ultrastructural localization of its protein by immunoelectron microscopy. In normal colon and stomach tissues, MTI-MMP mRNA and protein were negative or faintly positive both in epithelial cells and in stromal fibroblasts, except in the fundic gland of the stomach, which showed the positivity for MTI-MMP. In contrast, gastrointestinal cancer tissue showed over-expression of MTI-MMP mRNA and protein both in cancer cells and in stromal cells (fibroblasts). Stromal fibroblasts also expressed mRNA for gelatinase A and type-I procollagen. Double immunohistochemistry revealed that macrophages were also positive for MTI-MMP. Immunoelectron microscopy showed that MTI-MMP was localized along the plasma membrane of cancer cells and macrophages and in rough endoplasmic reticulum of fibroblasts. The present study reveals a dual over-expression pattern of MTI-MMP both in cancer cells and in stromal fibroblasts; the expression in cancer cells may be related to the invasive growth, whereas that in fibroblasts may be related to the tissue remodeling process caused by invasive growth of cancer cells.
Int J Cancer 1996 Nov 27
PMID:Dual over-expression pattern of membrane-type metalloproteinase-1 in cancer and stromal cells in human gastrointestinal carcinoma revealed by in situ hybridization and immunoelectron microscopy. 893 35

The matrix-degrading metalloproteinases (MMPs) have been implicated in tumor invasion and metastasis. Recently it has become clear that the expression of MMPs in tumors is frequently localized to stromal cells surrounding malignant tumor cells. In the mouse skin model of multi-stage carcinogenesis, the MMP stromelysin is expressed in stromal fibroblast-like cells surrounding benign and malignant squamous cell carcinomas. Conversion of these tumors to highly invasive and metastatic spindle-cell tumors is however, associated with the expression of stromelysin-1 mRNA in the tumor cells themselves. The analysis of MMPs in human colon adenocarcinomas at different stages of tumor progression revealed that matrilysin was the only MMP expressed in the tumor cells, while stromelysin-1 and stromelysin-3 mRNA was detected in stromal cells surrounding malignant tumor cells. Matrilysin mRNA is detected in benign tumors as well as malignant tumor cells, and the relative level and percent of tumors expressing matrilysin correlates with the stage of tumor progression. These results suggest that both stromal and tumor cell metalloproteinases may contribute to tumor invasion and metastasis, and also suggests that MMPs may play a role in earlier events in the tumor progression pathway. A potential role for MMPs in tumor growth is illustrated by results which suggest that the expression of matrilysin in human colon cancer-derived cells increases tumorigenicity following injection into the cecum, and that transgenic mice expressing matrilysin mRNA show a marked proliferative response. MMPs may therefore play multiple roles in tumor progression.
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PMID:Matrix-degrading metalloproteinases in tumor progression. 898 72

A critical attribute of invasive carcinomas is their ability to degrade components of the extracellular matrix, a process achieved by the matrix metalloproteases. In the human squamous cell carcinoma cell line II-4, mRNA and protein expression of the matrix metalloprotease matrilysin was observed to be significantly higher in confluent than in log-phase growth conditions. The purpose of this study was to determine the basis for this switch in constitutive matrilysin expression. Conditioned medium from confluent cultures did not induce matrilysin in log-phase cultures, nor did conditioned medium from log-phase cultures repress matrilysin expression in confluent cultures. Thus, matrilysin expression was found not to be controlled by factors autocrine product. Matrilysin protein levels were, however, found to be directly correlated to the degree of cell-cell contact. Incubation of confluent cultures in 30 microM calcium medium, which disrupts E-cadherin-mediated cell-cell contact, was subsequently found to inhibit matrilysin expression, as did treatment with an anti-E-cadherin-neutralizing antibody. These results demonstrate that the degree of cell-cell contact mediated by the E-cadherin cell-adhesion molecule can influence constitutive metalloprotease expression levels in cultured squamous cell carcinoma cells.
J Cancer Res Clin Oncol 1997
PMID:Regulation of matrilysin expression in cells of squamous cell carcinoma by E-cadherin-mediated cell-cell contact. 899 35


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