Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The 92 kDa matrix metalloproteinase (gelatinase B, MMP-9) plays a major role in the facilitation of tumor metastasis and in inflammatory disorders characterized by excessive matrix protein destruction. MMP-9 is transcriptionally induced in multiple cell types by exposure to the inflammatory mediators bacterial endotoxin, interleukin-1 (IL-1) or tumor necrosis factor-alpha (TNF-alpha). CT-2519, (1-(5-isothiocyanatohexyl)-3,7-dimethylxanthine), a synthetic small molecule from an anti-inflammatory compound library, was evaluated for its effect on endotoxin and cytokine-induced MMP-9 synthesis by a monocytic leukemic cell line, THP-1, and a monocyte/macrophage line, RAW 264.7. CT-2519 dose-dependently inhibited endotoxin and cytokine-induced synthesis of MMP-9 by these cells. Furthermore, both MMP-9 secretion and matrix invasion by cells of a human fibrosarcoma cell line, HT-1080, were inhibited by CT-2519 in a dose-dependent manner. Northern blot analyses and studies utilizing MMP-9 promoter constructs indicated that the inhibitory action of CT-2519 occurs at the level of transcriptional suppression. Given the observation that cellular activation by endotoxin, IL-1 and TNF-alpha may be mediated, at least in part, through induction of certain species of phosphatidic acid (PA), the effect of CT-2519 on lipid levels was analyzed. CT-2519 effectively reduced endotoxin-mediated increases in particular cellular lipid levels. Pharmacologic modulation of cytokine-dependent gene products, such as MMP-9, may offer an important therapeutic approach to the treatment of neoplastic and inflammatory disorders.
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PMID:Pharmacological inhibition of gelatinase B induction and tumor cell invasion. 875 12

We examined production and tissue localization of matrix metalloproteinase (MMP)-1 (tissue collagenase), MMP-2 (gelatinase A), MMP-3 (stromelysin-1), MMP-9 (gelatinase B), tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in human breast carcinomas. In more than half of the cases, MMP-1, MMP-2, MMP-9, TIMP-1 and TIMP-2 were immunolocalized in carcinoma cells and MMP-2 was on the carcinoma cell membranes as well, whereas MMP-3 was positively stained in less than 15% of the cases. MMP-1 staining in carcinoma cells was significantly higher in scirrhous carcinoma than in other types of carcinoma. MMP-9 expression was remarkably higher in the carcinoma cases with lymphnode metastasis than in the non-metastatic cases. MMP-3 was mainly expressed in T-lymphocytes infiltrated in the tumor stroma. Stromal fibroblasts were positive for all these MMPs except for MMP-3. The TIMP-1 levels released into the culture media by carcinoma tissues were significantly lower than those by fibroadenoma tissues, although there were no significant differences in the levels of MMP-1, MMP-2, MMP-9 and TIMP-2. Gelatin zymographical analyses showed that the activation rate of the zymogen of MMP-2 (proMMP-2) is significantly higher in the more advanced carcinoma group with lymphnode metastasis than in the metastasis-negative and fibroadenoma groups. These data indicate that MMP-1, MMP-2 and MMP-9 are highly expressed in human breast carcinoma tissue and suggest that activation of proMMP-2 may be an indicator of lymphnode metastasis of the breast carcinoma.
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PMID:Production of matrix metalloproteinases and tissue inhibitors of metalloproteinases in human breast carcinomas. 876 24

Matrix metalloproteinases play an important role in tumor invasion, angiogenesis and inflammatory tissue destruction. The 72-kd gelatinase A is the most widely distributed. Along with the 92-kd gelatinase B, it plays an important role in basement membrane turnover. Gelatinase A is secreted as progelatinase A and, when activated, can cause extracellular matrix destruction. The physiologic mechanism of this activation is not well understood. Based on the importance of endothelial cells in inflammation and cancer, we sought in this study to systematically study the PMA-induced activation of endothelial cell progelatinase A. Using HUVEC, we demonstrated that PMA-induced activation of progelatinase A in these vascular endothelial cells (a) was protein kinase C-dependent as it was blocked by H-7; (b) occurred through cell-mediated events as PMA was unable to activate progelatinase A in a cell-free system and that low dose tissue inhibitor of metalloproteinases-2, but not tissue inhibitor of metalloproteinases-1, totally inhibited PMA-induced activation; (c) was accompanied by an increase in the membrane-type matrix metalloproteinase (MT-MMP). We also found that the combination of PMA and the cytokine tumor necrosis factor-alpha increased HUVEC secretion and activation of gelatinase B. In conclusion, our data show that PMA activation of vascular endothelial cell progelatinase A is a cell membrane event that is at least partially mediated through a PKC-dependent mechanism and is accompanied by an increase synthesis of MT-MMP. These data suggest a role for MT-MMP in the activation of progelatinase A in vascular endothelial cells.
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PMID:Activation of human umbilical vein endothelial cell progelatinase A by phorbol myristate acetate: a protein kinase C-dependent mechanism involving a membrane-type matrix metalloproteinase. 878 Jan 71

Implantation and placental development are dependent upon trophoblast invasion of the endometrium. While the villous trophoblast does not display invasive behavior, the extravillous cytotrophoblast is highly invasive. By cloning BeWo choriocarcinoma cells, we have isolated two distinct clones that share similarities with villous and extravillous cytotrophoblasts. When cultured at the surface of a type I collagen gel, BeWo MC-1 cells were not invasive, whereas BeWo MC-2 cells rapidly invaded this matrix. When injected subcutaneously in nude mice, BeWo MC-1 cells developed a localized tumor and BeWo MC-2 cells developed larger tumors with micrometastases. Gelatinase A expression and minute amounts of gelatinase B were detected in the parental cell line and in both clones. However, the parental and the BeWo MC-2 cells secreted 5-to 10-fold more gelatinase A than the BeWo MC-1 cells. Laminin and matrigel stimulated the production of gelatinase A in BeWo MC-2 cells. Type I collagen promoted the conversion of the 72-kDa progelatinase A in an active enzyme only in parental BeWo and in BeWo MC-2 cells. These clones provide an interesting model for studying the complex mechanisms regulating implantation as well as the controlled invasiveness during implantation compared to tumor invasion.
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PMID:Cloning of choriocarcinoma cells shows that invasion correlates with expression and activation of gelatinase A. 883 62

Gelatinase B is a regulated matrix metalloproteinase with important role in the remodeling of extracellular matrix and many pathological conditions such as tumor invasion and rheumatoid arthritis, physiological processes including embryonic growth and development, migration of blood leukocytes into tissues and tissue remodeling. Elevated levels of certain MMPs are believed to be associated with various pathological states. We cloned the 5'-flanking 600 bp sequence of human gelatinase B gene by PCR, which controls the expression of the gene by ligating it to the chloramphenicol acetyltransferase gene. Four kinds of cell lines were used to transiently transfect. Deletion analysis revealed that 100 bp (-600 to -500 bp) contributed positively to induction by tumour necrosis factor. The 100 bp contains NF-kappa B site, Ap-1 site, PEA3 and Sp-1 site. The expression of the human gelatinase B gene varied in different cells in the presence of TNF.NF-kappa B factor may play an important role in regulating the gene expression. Comparison of the finding with those for the promoter of gelatinase A, collagenase and stromelysin shows that the determinant for the inducibility of the gelatinase B gene is more complex.
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PMID:Molecular mechanism of transcriptional activation of human gelatinase B by proximal promoter. 884 71

We determined whether the upregulation of several metastasis-related genes in human colon carcinoma (HCC) cells implanted into the cecal wall of nude mice precedes HCC invasion of the muscle layer and subserosa and, ultimately, distant metastasis. HCC KM12SM cells were implanted into the subcutis (ectopic) or cecal wall (orthotopic). At weekly intervals for up to 6 weeks, cecectomy and resection of SC tumors were performed on different groups of mice. Survival and metastasis were assessed at 13 weeks. During the first 2 weeks after orthotopic implantation, the HCC cells grew progressively in the mucosa and submucosal layers of the cecum. By the third week, the cells invaded the muscularis propria and then the serosa. All mice undergoing cecectomy at weeks 1 and 2 were cured, whereas those undergoing cecectomy at later weeks were not. In situ hybridization analysis for expression of several metastasis-related genes-epidermal growth factor receptor (EGF-R), basic fibroblast growth factor (bFGF), collagenase type IV, and E-cadherin-revealed that the expression level of EGF-R, bFGF, and collagenase type IV in the early cecal tumors was low but increased just before invasion of the muscularis propria. At all times, the level of gene expression in the cecal tumors was higher than in the SC tumors. In contrast, the expression level of E-cadherin remained constant and did not differ between tumors in ectopic or orthotopic organs. The data suggest that the upregulation of some metastasis-related genes precedes tumor cell invasion and production of metastasis.
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PMID:Progressive upregulation of metastasis-related genes in human colon cancer cells implanted into the cecum of nude mice. 886 66

Gelatinase B is a member of the metalloproteinase family of enzymes that degrade the extracellular matrix under normal and pathological conditions, including autoimmune diseases and tumor cell dissemination. In the present work, we describe a simple and reliable method that allows qualitative and quantitative measurements of a specific enzymatic reaction (mediated here by gelatinase B) by flow cytometry using fluorochrome-labeled substrate coated on polystyrene microspheres. Using this approach, proteolytic degradation can be monitored by the decrease of the fluorescence emitted by the microspheres following incubation with the enzyme. In most of the experiments, the signal-to-noise ratio between autofluorescent microspheres and those coated with the fluorescein isothiocyanate (FITC)-labeled substrate was near 500. This ratio allows one to measure accurately the enzymatic activity in the presence of chemical or biological inhibitors. FITC labeling and passive adsorption of substrates on the solid support did not cause significant conformational changes or steric hindrance that would interfere with the proteolytic activity of gelatinase B. This method constitutes a powerful tool for the measurement, on a routine basis, of the net activity resulting from the balance between the gelatinase B activity and the presence of natural inhibitors and for the identification of new metalloproteinase inhibitors that could suppress the excessive proteolytic activity that characterizes many disease processes.
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PMID:Flow cytometric analysis of gelatinase B (MMP-9) activity using immobilized fluorescent substrate on microspheres. 894 45

To examine the possible involvement of gelatinase B in human hepatocellular carcinoma (HCC), cellular localization of transcripts and protein of gelatinase B were studied by using in situ hybridization and immunohistochemistry. Transcripts for gelatinase B were observed in tumor cells in 22 cases of 27 HCCs and also in dysplastic nodules. However, there was no significant difference in the expression among histological grades of HCC. The expression was mostly homogeneous, but the intensity varied with the nodules. Of 13 cases with capsular invasion, 12 expressed gelatinase B, whereas 10 of 14 without capsular invasion did (P < 0.05). Gelatinase B transcripts were commonly observed in the sinusoidal cells of the hepatic lobules, in mesenchymal cells both in fibrous capsules and around the necrosis, and also in some undefined cells of the portal tracts of noncancerous liver. Localization of gelatinase B protein was mostly similar to but sometimes different from that of the transcripts in cancer nodules. In conclusion, the expression of gelatinase B appears to be an important characteristic of malignant transformation of hepatocytes. The findings suggest that gelatinase B synthesized by cancer cells plays an important role in the growth and invasion of HCC by degrading surrounding extracellular matrices.
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PMID:Cellular distribution of 92-kd type IV collagenase/gelatinase B in human hepatocellular carcinoma. 895 17

The possible application of proteinase inhibitors in the support of anti-tumor chemotherapy requires profound knowledge of the proteinases involved in malignant processes. Therefore, the occurrence of cathepsins B, D, H, L and S and of gelatinases, urokinase plasminogen activator and stromelysins was studied in biopsies of aggressive human bone metastases, of low invading basal cell carcinomas, and in normal placenta as control, by activity measurements and zymographic techniques. Cathepsin B and L, as well as gelatinase B, were shown to be overexpressed in bone metastases, suggesting a function during the metastatic process. Subcellular fractionation allowed detection of differential sorting of cathepsin B and gelatinases in metastatic tissue and also in normal human placenta. Plasma membrane binding could be demonstrated for both cathepsin B and gelatinase B. Whereas cathepsin B is at least partially bound to plasma membranes via alpha 2-macroglobulin and its LRP/alpha 2-macroglobulin receptor, gelatinase B binds to plasma membranes by an unknown mechanism.
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PMID:Expression, subcellular distribution and plasma membrane binding of cathepsin B and gelatinases in bone metastatic tissue. 896 Mar 70

During cancer progression, tumor cells interact with stromal cells. As a consequence, matrix metalloproteinases are produced that contribute to the degradation of the extracellular matrix. This study used coculture systems to investigate fibroblast interaction with three colon cancer cell lines isolated from a single patient. Cells from primary colorectal carcinoma, but not from corresponding liver or lymph node metastases, induced gelatinase B expression by fibroblasts of different tissue origin. Remarkably, direct cell-cell contact was required for this induction, which occurred at the pretranslational level (as revealed by Northern blot analysis) and was completely blocked by anti-beta1 integrin monoclonal antibody, but only partially blocked by anti-alpha5 or anti-alpha(v). Induction was also inhibited by cytochalasin D, staurosporine, or dexamethasone, suggesting the need, respectively, for an organized actin cytoskeleton, protein kinase C, and AP-1-driven gene transcription. Our data suggest that direct tumor-stromal cell contact is one inductive event involved in matrix metalloproteinase expression by stromal cells.
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PMID:Induction of fibroblast gelatinase B expression by direct contact with cell lines derived from primary tumor but not from metastases. 896 8


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