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)

The expression of stromelysin, a major matrix metalloproteinase of connective tissues, is regulated by several cytokines, growth factors, protooncogenes as well as by 12-O-tetradecanoylphorbol-13-acetate (TPA). The human stromelysin gene promoter contains an activator protein-1 (Fos/Jun) binding site at -70, which is required for basal expression but is not necessary for the TPA response. In this study, using promoter deletion mutants in transient gene transfection experiments, we first identify the sequence from -220 to -202 as necessary for the TPA response of the stromelysin gene. Further, among the restriction fragments from the 1.3-kilobase long promoter, only the proximal fragment (-274 to -101) conferred a TPA response on the heterologous thymidine kinase gene promoter. The -220 to -202 sequence contains two copies of a motif similar to the polyomavirus enhancer A-binding protein-3 (PEA-3) site, which binds the Ets family of oncoproteins and transcription factors. Point mutations of either one of the two PEA-3 sites, in the 1.3-kilobase long stromelysin promoter context, reduced basal gene expression. However, only the mutation of the proximal, but not the distal PEA-3 site, significantly inhibited the TPA response. In cotransfection experiments, the Ets-2 protein transactivated the stromelysin promoter and the promoter proximal fragment containing the PEA-3 sites but not the promoters containing mutated PEA-3 sites. These data suggest that the PEA-3 site, but not the activator protein-1 site, and Ets-2 protein have a major role in the TPA induction of the human stromelysin gene transcription.
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PMID:A polyomavirus enhancer A-binding protein-3 site and Ets-2 protein have a major role in the 12-O-tetradecanoylphorbol-13-acetate response of the human stromelysin gene. 846 55

Stromelysin-1, matrix metalloproteinase-3 (MMP-3), is an important endopeptidase selectively expressed by somatic cells in organ tissues. The renal tubulointerstitium, for example, comprises tubular epithelium and interstitial fibroblasts forming the principal mass of the kidney. We observed that mRNA encoding stromelysin-1 is detectable in murine renal fibroblasts, but not in proximal tubular epithelium. Transcripts measured by RNase protection assay in renal fibroblasts increase following exposure to phorbol ester, and thereafter, activated stromelysin-1 protein can be detected in culture media by Western blotting. A 6.4 Kb genomic clone containing the putative stromelysin-1 promoter was isolated and a relevant 2.1 Kb PstI restriction fragment including 2.1 Kb of the immediate 5'-flanking region was sequenced on both strands. Two transcriptional start sites were identified by primer extension; the major start site corresponded to a previously established position in the rat promoter, and a second undescribed minor transcriptional start site was located 16 bp upstream of the primary site. A HiNF-A chromatin-activating element at -106 bp was found in the early promoter region of pR336 and an active AP-1 site at -72 bp with an Ets/PEA-3 motif at -203 bp was suggested by transient transfection of luciferase minigenes into renal fibroblasts responsive to phorbol ester. This Ets element was identical to a site in the early promoter of the fibroblast-specific gene FSP1. A baseline enhancement in activity of pR336 in fibroblasts was further observed with the addition of 5' flanking sequence out to -1980 bp. This additional region of flanking sequence contains two modular regions: one of multiple PEA-3 elements between -684 bp and -1955 bp and a second region between -1929 bp and -1980 bps containing a second AP-1 site at -1929 bp, a MBF-1/ MEP-1 metal binding site, and a PPAR peroxisome proliferator element at -1950 bp. Our findings implicate a gene structure with expected activity in a mesenchymal phenotype. The PKC-dependent regulation of the stromelysin-1 gene supports the notion that it may be modulated during inflammation or tissue remodeling.
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PMID:Identification of promoter activity and differential expression of transcripts encoding the murine stromelysin-1 gene in renal cells. 921 54

Matrix Metalloproteinases (MMPs) play a crucial role in breast cancer metastasis. We examined the mRNA and protein expression of several MMPs in brain- and bone-seeking clones of MDA-MB-231 breast cancer cells, their transcriptional regulation and their functional role in the metastatic process. MMP mRNA expression was examined using real-time reverse transcription polymerase chain reaction. Protein expression was examined using enzyme linked immunosorbent essay (ELISA). The inducibility of mRNA and protein expression was tested with TPA (phorbol 12-myristate 13-acetate; 50 microM); epidermal growth factor and transforming growth factor beta (20 ng/ml both). Migration and invasion assays were performed with the QCM 96-Well Migration/Invasion Assay (8 microm; Chemicon) over 24 h with or without specific MMPs inhibitors (MMP Inhibitor I Mix (5 microM); MMP-2/MMP-9 Inhibitor III (50 microM); EMD Biosciences). We found significantly higher mRNA expression of MMP-1 and -9 in brain-seeking 231-clones in comparison to -bone and -parental cells. In contrast, the mRNA expression of MMP-3 and -14 was comparable in all cells lines examined and MMP-13 expression was lower in both selective metastatic lines. MMP-2 and -8 were not expressed. ELISA revealed a higher amount of total as well as active MMP-1 and -9 in brain-seeking cells. TPA stimulation showed that MMP-1 and -9 transcription was inducible on the mRNA and protein level in 231-parental but not in 231-brain or -bone. 231-brain showed the highest migration and invasive capacity which could be decreased by the application of MMP-1 and/or MMP-9 inhibitor. Our results indicate functional importance of MMP-1 and -9 overexpression in brain metastasis in an in vitro model.
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PMID:Differential expression of matrix metalloproteinases in brain- and bone-seeking clones of metastatic MDA-MB-231 breast cancer cells. 1685 Jan 7