Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ten cases of malignant mesothelioma (MM), as diagnosed by clinical history and light and electron microscopy, were studied with polyclonal antibodies directed against the basement membrane-specific proteins, type IV collagen and laminin, as well as with monoclonal antibodies which recognize two epitopes of the laminin receptor (LR). All formalin-fixed, paraffin-embedded mesothelioma tissues examined demonstrated intracytoplasmic immunoreactivity for the basement membrane proteins. Extracellular staining was minimal, analogous to the staining reactions observed in adenocarcinomas of the breast and lung, which on light microscopy mimicked the morphologic appearance of MM. Similarly, LRs were identified on MM cells by intense positive staining. Immunoreactivity was also evident on nonneoplastic mesothelioma and adenocarcinoma cells but with greater heterogeneity and less intensity. It may be concluded from these results that (a) malignant mesotheliomas have the ability to synthesize components of the basement membrane; (b) enhanced attachment to extracellular matrix by MM would be anticipated as laminin receptors are present in large numbers on the surface of mesothelioma cells; (c) the reason for lack of intensiveness by MM cells remains speculative; type IV-specific collagenase may play a role in regulating this function in these tumor cells.
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PMID:Immunoreactivity in malignant mesotheliomas with antibodies to basement membrane components and their receptors. 213 26

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

Because matrix metalloproteinases (MMPs) degrade extracellular matrix, including basement membrane, and because tissue inhibitors of MMP (TIMPs) suppress MMP activities, MMPs and TIMPs are considered to play important roles in invasion and metastasis in many malignancies. We examined immunohistochemically the expression of MMPs (MMP-1, -2, -3, -7, and -9), TIMPs (TIMP-1 and -2), and collagens (types I, III, and IV) in 16 patients with pleural malignant mesothelioma (PMM; 8 with the epithelial, 4 with the sarcomatous, and 4 with the biphasic type). Electron microscopy revealed that the tumor cells in all types possessed the characteristics of malignant mesotheliomas, including numerous microvilli and moderate amounts of intermediate filaments. Basement lamina was present only focally. The proliferative Ki67 index was at a high level, compared with values reported in various other malignancies. Positive staining for MMP-1 was observed in most tumor cells in all 16 patients (100%). MMP-2 was expressed in most tumor cells in 2 patients (13%). In contrast, MMP-3, -7, and -9 were not detected in any PMM. TIMP-1 and TIMP-2 were expressed in 3 patients (19%) and 2 patients (13%), respectively. The stromal cells were simultaneously positive for MMPs or TIMPs in the patients whose tumor parenchymal cells were positive for each enzyme. These results indicate that the expression of MMP-1 and MMP-2 may be related to PMM invasion and spread. In particular, as MMP-1 was overexpressed in contrast to the lower expression of TIMP-1, MMP-1 is strongly suggested to play an important role in PMM invasion by degrading the tumor stroma. In spite of general agreement that epithelial-type PMM has a better prognosis than other types, there was no significant difference in the Ki67 index among the histological types of PMM.
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PMID:Expression of matrix metalloproteinases, tissue inhibitors of metalloproteinase, collagens, and Ki67 antigen in pleural malignant mesothelioma: an immunohistochemical and electron microscopic study. 1211 3