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)

Matrilysin is a member of the matrix metalloproteinase gene family which is believed to play an important role in tumor progression. Expression of matrilysin mRNA was examined by reverse transcription-polymerase chain reaction combined with Southern blot analysis in 46 human primary gastric cancers. Overexpression of matrilysin was observed in 28 (61%) of gastric cancer tissues. The positive expression ratio of matrilysin was significantly higher in the gastric cancers of subserosa or beyond it than in those within the submucosal layer. Immunohistochemical study with anti-matrilysin monoclonal antibody revealed that matrilysin was mainly expressed on cancer cells but not or very weakly expressed on other cells. In addition, an activated form of matrilysin detected by zymographic analysis was observed in gastric cancer tissues whereas none was detected in non-cancerous tissues, suggesting that matrilysin may directly and powerfully contribute to the invasion step of human gastric cancer. In order to gain more insight into the relationship of this metalloproteinase to invasive activity, we also modulated the expression of matrilysin in gastric cancer cells by DNA transfection using gastric cancer cell lines. Overexpression of matrilysin rendered the gastric cancer cells more invasive in vitro. Concomitant with clinical investigations, matrilysin may be an important metalloproteinase in the progression of gastric cancer.
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PMID:Relation of matrilysin messenger RNA expression with invasive activity in human gastric cancer. 962 10

We show that osteopontin (OPN), bone sialoprotein (BSP) and GRGDSP peptides, in solution, induce activation of metalloproteinase-2 (MMP-2) secreted by human GCT23 giant cell tumour cells. Activation of MMP-2 is RGD sequence dependent, possibly involves anti-alphaVbeta3 integrins, is preceded by a change from spread to rounded cell morphology and is mimicked by the actin depolymerising agent cytochalasin B. Cells that had spread on OPN, BSP and GRGDSP substrata failed to activate MMP-2, but subsequent addition of soluble GRGDSP induced rounding and MMP-2 activation. Activation induced by GRGDSP and cytochalasin B was cell mediated, inhibited by EDTA, tissue inhibitor of metalloproteinase-2 (TIMP-2) and carboxyl terminal MMP-2 consistent with a role for membrane type (MT)-MMP but did not involve urokinase, plasmin or thrombin activity. Activation induced by GRGDSP and cytochalasin B, but not cell rounding, was inhibited by herbimycin A, cycloheximide and actinomycin D, suggesting a role for tyrosine kinases, protein and RNA synthesis, but was not associated with changes in mRNA for MT-MMP-1, MMP-1, MMP-2, TIMP-1 or TIMP-2. GRGDSP and cytochalasin B enhanced levels of membrane-associated pro- and active form MMP-1 and MMP-2 but not MT-MMP-1, stimulated cell surface MMP-1 staining and induced that of MT-MMP-1, MMP-2 and TIMP-2. This was consistent with the possible relocation of constitutive MT-MMP-1 to the cell surface as a prerequisite for subsequent cell surface MMP-2/TIMP-2/MT-MMP-1 complex formation and to the potential induction of conditions favourable for reciprocal cell surface MMP-1/MMP-2 activation. Our data provide a novel insight into interactions between RGD containing bone matrices, GCT cells and MMPs of potential relevance to GCT pathology.
Int J Cancer 1998 Jul 03
PMID:Activation of MMP-2 by human GCT23 giant cell tumour cells induced by osteopontin, bone sialoprotein and GRGDSP peptides is RGD and cell shape change dependent. 963 98

This article describes the significance of mRNA expression of VEGF, MMP-2, MMP-9, and MT1-MMP in human colorectal cancer metastases, particularly hepatic metastases. The levels of gene expression were quantified by Northern blot hybridization in tumor and nontumor tissues obtained from 66 primary cases. Significantly higher levels of expression of VEGF mRNA were observed in patients with synchronous hepatic metastases (n = 15) and/or lymph node metastases than in those without. Patients with synchronous hepatic metastases had significantly higher levels of mRNA expression of all MMP genes than in those without, and no apparent correlation was seen between MMP mRNA expression and other clinicopathologic variables. Also in a study including 4 cases of metachronous hepatic metastases after surgery. VEGF, MMP-9, and MT1-MMP mRNA expression were significantly higher in patients with hepatic metastases than in those without, indicating that these are predictable markers for hepatic metastases. Immunohistochemical examination revealed that VEGF and MT1-MMP were localized mainly in cancer cells, whereas MMP-2 and MMP-9 were distributed throughout stromal cells such as fibroblasts and leukocytes in tumor tissues.
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PMID:[Implication of VEGF and MMPs in hepatic metastasis of human colon cancer]. 974 24

The activation of zymogen and the amount of proteinase and its inhibition are important in determining the eventual activity of matrix-degrading enzymes involved in tumor aggressiveness. To evaluate a gene complement leading to matrix metalloproteinase 2 (MMP-2; Mr 72,000 gelatinase) activity, membrane type 1 MMP (MT1-MMP), urokinase-type plasminogen activator, MMP-2, and tissue inhibitor of metalloproteinase 2 transcriptional levels were measured in gastric carcinoma biopsies. Comparative tumor:normal tissue reverse transcription-PCR in a cohort of 25 patients revealed up to a 10-fold difference in the expression of MT1-MMP, a metalloproteinase that has been proposed as a membrane receptor activator of MMP-2; a 1-unit increment resulted in a 30% risk to survival. A 20% risk also resulted from a 1-unit increment in the MT1-MMP: MMP-2 ratio, which showed differences of up to 15-fold. Instead, the expression of urokinase-type plasminogen activator, which trips off a cascade ending in the activation of MMP-2, as well as the expression of MMP-2 itself and its inhibitor, tissue inhibitor of metalloproteinase 2, lacked correlation with patient follow-up. Zymography revealed MMP-2 activities that were often in conflict with the transcription results and also with follow-up. The results suggest the evaluation of MT1-MMP and/or MT1-MMP:MMP-2 transcription as a new preoperative molecular-level prognostic factor for gastric carcinoma.
Clin Cancer Res 1998 Sep
PMID:Augmented membrane type 1 matrix metalloproteinase (MT1-MMP):MMP-2 messenger RNA ratio in gastric carcinomas with poor prognosis. 974 37

Degradation of the extracellular matrix is necessary for invasion and metastasis by cancer cells. Two gelatinolytic matrix metalloproteinase enzymes, MMP-2 and MMP-9, are supposed to be key enzymes in this process. The purpose of this study was to correlate the presence of MMP-2, MMP-9 and their inhibitors with the tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2 RNA using reverse transcriptase PCR technique with tumor stage in 17 samples of renal cell carcinoma. The ratio of tissues expressing MMP-2 and MMP-9 to those expressing TIMP-1 and TIMP-2 was defined to be 1 in normal kidney tissue. This MMP:TIMP ratio was significantly increased to 2.43 (standard deviation, SD = 0.8) in locally confined renal cell carcinoma and to 4.86 (SD = 1.1) in advanced carcinoma (p <0.01). In primary tumor cell lines the ratio of MMP:TIMP expression was 3.44 (SD = 0.6). These data suggest that the balance of MMP-2 and MMP-9 to TIMP-1 and TIMP-2 expression is an essential factor in the aggressiveness of renal cell carcinoma.
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PMID:Expression of metalloproteinase 2 and 9 and their inhibitors in renal cell carcinoma. 978 85

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) play a significant role in regulating angiogenesis, the process of new blood vessel formation. Interstitial collagenase (MMP-1), 72 kDa gelatinase A/type IV collagenase (MMP-2), and 92 kDa gelatinase B/type IV collagenase (MMP-9) dissolve extracellular matrix (ECM) and may initiate and promote angiogenesis. TIMP-1, TIMP-2, TIMP-3, and possibly, TIMP-4 inhibit neovascularization. A new paradigm is emerging that matrilysin (MMP-7), MMP-9, and metalloelastase (MMP-12) may block angiogenesis by converting plasminogen to angiostatin, which is one of the most potent angiogenesis antagonists. MMPs and TIMPs play a complex role in regulating angiogenesis. An understanding of the biochemical and cellular pathways and mechanisms of angiogenesis will provide important information to allow the control of angiogenesis, e.g. the stimulation of angiogenesis for coronary collateral circulation formation; while the inhibition for treating arthritis and cancer.
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PMID:Complex role of matrix metalloproteinases in angiogenesis. 979 30

Matrix metalloproteinase (MMP) activity has been associated with tumor invasion and metastasis in many different tumor types, but recent studies also support a role for these enzymes in earlier stages of the tumor progression continuum. Specifically, the expression pattern of MMPs in benign human and mouse gastrointestinal tumors suggests that they may function in the development or growth of non-invasive tumors. To address the contribution of MMP activity to the development of intestinal adenomas, we administered the synthetic MMP inhibitor batimastat and expressed the tissue inhibitor of metalloproteinases-1 (TIMP-1) in the gastrointestinal tract of Min mice, which spontaneously develop pre-malignant small and large intestinal tumors. Batimastat administration resulted in a 48% decrease in the number of Min tumors. This reduction in tumor number is similar to that observed in mice lacking the metalloproteinase matrilysin, and demonstrates the therapeutic and chemopreventive potential of MMP inhibitors for pre-malignant intestinal tumors. In contrast, forced TIMP-1 expression in transgenic mice had no effect or, in one line, unexpectedly augmented Min tumor multiplicity by 32%. This observation supports an in vivo tumor-promoting activity of TIMP-1 that could be related to the growth stimulatory effects of TIMP that have been documented in vitro. Taken together, these 2 approaches of modulating MMP activity in Min mice support a critical function of MMPs in Min tumorigenesis, underscore the importance of an MMP/inhibitor balance in maintaining tissue homeostasis and demonstrate that endogenous MMP inhibitors can have complex effects in particular cellular contexts.
Int J Cancer 1998 Nov 23
PMID:Differing effects of endogenous and synthetic inhibitors of metalloproteinases on intestinal tumorigenesis. 980 34

Dietary genistein, a natural flavone compound found in soy, has been proposed to be responsible for the low rate of breast cancer in Asian women. The cellular mechanisms of genistein's chemopreventive effects in vio have been largely unexplored. In our previous studies, we found that genistein exerted pronounced antiproliferative effects on both estrogen receptor-positive and -negative human breast carcinoma cells through G2-M arrest, induction of p21WAF1/CIP1 expression, and apoptosis. Because chemopreventive effects need not be limited to antiproliferation, we decided to examine whether genistein exerted other suppressive effects on breast carcinoma progression. Genistein inhibited invasion in vitro of MCF-7 and MDA-MB-231 cells. This inhibition was characterized by down-regulation of MMP (matrix metalloproteinase)-9 and up-regulation of tissue inhibitor of metalloproteinase-1, the former of which was transcriptionally regulated at activation protein-1 sites in the MMP-9 promoter. Genistein's in vitro effects on MMP-9 and tissue inhibitor of metalloproteinase-1 were also demonstrated in in vivo studies in nude mouse xenografts of MDA-MB-231 and MCF-7 cells. In these xenograft studies, genistein inhibited tumor growth, stimulated apoptosis, and upregulated p21WAF1/CIP1 expression. In the MDA-MB-231 xenograft, genistein also inhibited angiogenesis by decreasing vessel density and decreasing the levels of vascular endothelial growth factor and transforming growth factor-beta1. These in vitro and in vivo studies demonstrate that genistein exerts multiple suppressive effects on breast carcinoma cells, suggesting that its mechanism of chemoprevention is pleiotropic.
Cancer Res 1998 Nov 01
PMID:Genistein exerts multiple suppressive effects on human breast carcinoma cells. 980 90

Overexpression of the epithelial specific matrix metalloproteinase matrilysin (MAT) has been correlated with enhanced tumorigenicity and tumor cell invasion using in vitro model systems. We have determined the effects of MAT expression on the development of mammary tumorigenesis using transgenic mice that express human MAT under the control of the mouse mammary tumor virus (MMTV)-long terminal repeat promoter/enhancer. Examination of mammary glands from multiparous MMTV-MAT animals revealed the development of premalignant hyperplastic alveolar nodules in 50% of aged females. MMTV-MAT mice were mated with MMTV-neu transgenic mice to determine the effect of MAT on neu-induced mammary tumorigenesis. Bigenic MMTV-MAT/neu female offspring developed primary mammary tumors approximately 13 weeks earlier than did MMTV-neu controls. The mechanism of enhanced neu-induced tumorigenesis was explored. No discernible difference in Neu receptor dimerization or activation was detected in MMTV-MAT/neu tumors or mammary glands compared to MMTV-neu controls. A similar percentage of MMTV-MAT/neu and MMTV-neu tumors acquired deletions in the neu transgene, which have previously been shown to result in constitutive receptor activation. The presence of premalignant nodules and the accelerated development of oncogene-induced mammary tumors suggest that expression of MAT in the mammary epithelium contributes to early-stage mammary tumorigenesis.
Cancer Res 1998 Dec 01
PMID:The matrix metalloproteinase matrilysin influences early-stage mammary tumorigenesis. 985 86

Activation of the matrix metalloproteinase 2 (MMP-2) has been shown to play a major role in the proteolysis of extracellular matrix (ECM) associated with tumor invasion. Although the precise mechanism of this activation remains elusive, levels of the membrane type 1-MMP (MT1-MMP) at the cell surface and of the tissue inhibitor of MMP-2 (TIMP-2) appear to be two important determinants. Induction of MMP-2 activation in cells cultivated on collagen type I gels indicated that the ECM is important in the regulation of this process. In this study, we show that SPARC/osteonectin, a small ECM-associated matricellular glycoprotein, can induce MMP-2 activation in two invasive breast cancer cell lines (MDA-MB-231 and BT549) but not in a noninvasive counterpart (MCF-7), which lacks MT1-MMP. Using a set of peptides from different regions of SPARC, we found that peptide 1.1 (corresponding to the NH2-terminal region of the protein) contained the activity that induced MMP-2 activation. Despite the requirement for MT1-MMP, seen in MCF-7 cells transfected with MT1-MMP, the activation of MMP-2 by SPARC peptide 1.1 was not associated with increased steady-state levels of MT1-MMP mRNA or protein in either MT1-MMP-transfected MCF-7 cells or constitutively expressing MDA-MB-231 and BT549 cells. We did, however, detect decreased levels of TIMP-2 protein in the media of cells incubated with peptide 1.1 or recombinant SPARC; thus, the induction of MMP-2 activation by SPARC might be due in part to a diminution of TIMP-2 protein. We conclude that SPARC, and specifically its NH2-terminal domain, regulates the activation of MMP-2 at the cell surface and is therefore likely to contribute to the proteolytic pathways associated with tumor invasion.
Cancer Res 1998 Dec 01
PMID:SPARC/osteonectin induces matrix metalloproteinase 2 activation in human breast cancer cell lines. 985 90


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