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)

Malignant glioma is a local invasive tumor in the central nervous system. The mRNA expression of five matrix metalloproteinases (MMPs) and two tissue inhibitors of metalloproteinases (TIMPs) was examined in surgical specimens of three brain tissues, two astrocytomas, four anaplastic astrocytomas and eleven glioblastomas, including recurrent one anaplastic astrocytoma and two glioblastomas. In the control brain tissues, mRNA expression was high for TIMP-2, low for gelatinase A and TIMP-1, and undetectable for gelatinase B, interstitial collagenase, stromelysin and matrilysin. Gelatinase B and TIMP-1 were concomitantly overexpressed in primary glioblastomas. In addition, the average expression level of gelatinase A increased 3.0 fold in astrocytomas and anaplastic astrocytomas and 6.0 fold in glioblastomas, compared to the brain tissues. Matrilysin was induced variably in more than half of the primary glioblastomas, and interstitial collagenase was slightly induced in some primary and recurrent glioblastomas. Stromelysin was characteristically not expressed in any gliomas, and the expression level of TIMP-2 did not significantly change in the gliomas. These results suggest that the concomitant increased expression of gelatinase A, gelatinase B and occasional matrilysin genes is associated with the malignancy of gliomas and accompanied by the increased expression of TIMP-1 gene.
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PMID:[Increased expression of gelatinases A and B, matrilysin and TIMP-1 genes in human malignant gliomas ]. 763 25

Antibodies were raised against seven major matrix metalloproteinases: stromelysin-1 (MMP-3), stromelysin-2 (MMP-10), stromelysin-3 (MMP-11), interstitial collagenase (MMP-1), M(r) 72,000 type IV collagenase (72 kDa type IV collagenase, MMP-2), M(r) 92,000 type IV collagenase (92 kDa type IV collagenase, MMP-9) and matrilysin (PUMP, MMP-7) as well as against prolyl 4-hydroxylase, to study the expression of these collagenolytic enzymes in normal liver in relation to the activity of collagen synthesis. Tissue samples of four normal human livers, three hepatocellular carcinomas and one cholangiocellular carcinoma were analysed. In normal liver we found expression of stromelysin-1, stromelysin-3, interstitial collagenase, M(r) 72,000 and M(r) 92,000 type IV collagenases and varying expression of prolyl 4-hydroxylase. Stromelysin-2 was inconsistently detectable; matrilysin was not found. In hepatocellular carcinoma the expression pattern of matrix metalloproteinases showed only minor changes compared with the normal tissue; stronger signals than in normal tissue were seen for stromelysin-1, and stromelysin-2 was also strongly positive. M(r) 72,000 and M(r) 92,000 type IV collagenases and interstitial collagenase were less strongly expressed; stromelysin-3 was unchanged. Expression of prolyl 4-hydroxylase was also increased compared with normal liver. Matrilysin was only seen in cholangiocellular carcinoma, which showed a completely different pattern of matrix metalloproteinase expression. Our results show that metalloproteinases are expressed in human liver with much greater abundance than previously described. Their expression pattern is not changed fundamentally in hepatocellular carcinoma but is completely different from that of other tumour tissues such as cholangiocellular carcinoma.
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PMID:Expression pattern of matrix metalloproteinases in human liver. 763 22

The gene expression of two type IV collagenases (matrix metalloproteinase [MMP]-2, a 72 kd type IV collagenase, and MMP-9, a 92 kd type IV collagenase) was investigated in carcinomas of the hypopharynx. We examined 27 cases operated on in our hospital by an in situ hybridization technique to detect their messenger RNA signals in cancer cells and surrounding stroma. Both signals were detected in all cancer nests and in stromal cells in the same specimens. Clinicopathologic studies showed a significant relationship between MMP-2 expression in the primary cancer and the outcome of treatment. Our present study suggests that hypopharyngeal squamous cell carcinoma producing MMP-2 has a high potential for invasion and metastasis and a poor outcome. The analysis of MMPs will be useful for treatment planning in hypopharyngeal carcinoma and for prognosis.
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PMID:Analysis of expression of matrix metalloproteinases-2 and -9 in hypopharyngeal squamous cell carcinoma by in situ hybridization. 766 15

The actions of human recombinant stromelysins-1 and -2, collagenase, gelatinases A and B and matrilysin on neonatal human proteoglycan aggregates were examined. With the exception of gelatinase B, aggrecan was degraded extensively by most metalloproteinases studied, whereas link protein showed only limited proteolysis. Sequencing studies of modified link protein components revealed that stromelysins-1 and -2, gelatinases A and B and collagenase cleaved specifically between His16 and Ile17, and matrilysin, stromelysin-2 and gelatinase A cleaved between Leu25 and Leu26. Cleavage at the former bond generated a link protein component with the same N-terminus as that isolated from newborn human cartilage. Based on previously determined in situ cleavage sites it is evident that matrix metalloproteinases are not solely responsible for the accumulation of link protein degradation products in adult human cartilage, indicating that additional proteolytic agents are involved in the normal catabolism of human cartilage matrix.
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PMID:Matrix metalloproteinases cleave at two distinct sites on human cartilage link protein. 769 69

From breast cancer cDNA libraries, we have cloned cDNAs that proved to correspond to the membrane-type matrix metalloproteinase (MT-MMP) recently identified in human placenta and proposed to be an activator of progelatinase A [Sato, H., Takino, T., Okada, Y., Cao, J., Shinagawa, A., Yamamoto, E. & Seiki, M. (1994) Nature (London) 370, 61-65]. Using one of these cDNAs as a probe, we have detected MT-MMP gene expression in all 83 human carcinoma specimens examined by RNA in situ hybridization and have found MT-MMP transcripts in fibroblastic cells of tumor stroma but not in cancer cells. Comparison with other MMP genes expressed in fibroblastic cells of human carcinomas indicated that the expression pattern of the MT-MMP gene was more closely related to that of the gelatinase A gene than to those of the stromelysin 3 or interstitial collagenase genes. These observations are consistent with the hypothesis that MT-MMP and gelatinase A are cooperating during tumor progression and strengthen the concept that proteolytic activities originating from the stromal component of human carcinomas have a critical role in tumor progression.
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PMID:Membrane-type matrix metalloproteinase (MT-MMP) gene is expressed in stromal cells of human colon, breast, and head and neck carcinomas. 770 15

Tissue inhibitor of metalloproteinases (TIMP)-2 forms a noncovalent complex with the precursor of matrix metalloproteinase 2 (proMMP-2, progelatinase A) through interaction of the C-terminal domain of each molecule. We have isolated the proMMP-2-TIMP-2 complex from the medium of human uterine cervical fibroblasts and investigated the processes involved in its activation by 4-aminophenylmercuric acetate (APMA). The treatment of the complex with APMA-activated proMMP-2 by disrupting the Cys73-Zn2+ interaction of the zymogen. This is triggered by perturbation of the proMMP-2 molecule, but not by the reaction of the SH group of Cys73 with APMA. The 'activated' proMMP-2 (proMMP-2*) formed a new complex with TIMP-2 by binding to the N-terminal inhibitory domain of the inhibitor without processing the propeptide. Thus the APMA-treated proMMP-2*-TIMP-2 complex exhibited no gelatinolytic activity. In the presence of a small amount of free MMP-2, however, proMMP-2* in the complex was converted into the 65 kDa MMP-2 by proteolytic attack of MMP-2, but the complex did not exhibit gelatinolytic activity. The gelatinolytic activity detected after APMA treatment was solely derived from the activation of free proMMP-2. The removal of the propeptide of the proMMP-2* bound to TIMP-2 was also observed by MMP-3 (stromelysin 1), but not by MMP-1 (interstitial collagenase). MMP-3 cleaved the Asn80-Tyr81 bond of proMMP-2*. On the other hand, when MMP-3 was incubated with the proMMP-2-TIMP-2 complex, it bound to TIMP-2 and rendered proMMP-2 readily activatable by APMA. These results indicate that the blockage of TIMP-2 of the complex with an active MMP is essential for the activation of proMMP-2 when it is complexed with TIMP-2.
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PMID:Steps involved in activation of the complex of pro-matrix metalloproteinase 2 (progelatinase A) and tissue inhibitor of metalloproteinases (TIMP)-2 by 4-aminophenylmercuric acetate. 777 54

Pneumocystis carinii pneumonia (PCP) is characterized by the formation of leaky alveoli and a foamy alveolar exudate. To induce PCP, male Wistar rats were immunosuppressed by oral dexamethasone treatment for 12 weeks, during which time all rats developed PCP. Bronchoalveolar lavage fluid (BALF) was analyzed at that time and at 1, 2, and 4 weeks after the cessation of dexamethasone treatment, during which time the rats were recovering from PCP and immunosuppression (and was compared with the BALF obtained from healthy control rats), for type IV collagenase, elastase, cathepsin G, and collagenase activities. Scores for 72-kDa (matrix metalloproteinase type [MMP-2]) and 92-kDa (MMP-9) type IV collagenase-gelatinase activities correlated with those for BALF macrophages (r = 0.58; P < 0.001) and neutrophils (r = 0.66; P < 0.001), respectively, suggesting that they may, in part, be derived from these cells. However, MMP-2 was constitutively expressed and may play a role in normal tissue remodeling. MMP-9 activity was highest in the group with PCP (1.8 +/- 0.37; P > 0.05), with a gradual decline (1.0 +/- 0.48 by week 4; P > 0.05) toward normal (0.67 +/- 0.42) during recovery, which suggests a role for it in tissue-destructive inflammatory events. In rats with PCP the endogenously active collagenase was present at high levels compared with those in healthy controls (2.6 +/- 0.69 versus 0.17 +/- 0.17, respectively; P < 0.01), but they returned to normal by week 4 of recovery (0.42 +/- 0.30; P > 0.05). Collagenase activity showed a correlation with cyst number (r = 0.57; P < 0.001). The BALF of rats with PCP also contained the serine proteinases, which may act as pro-MMP activators. Ultramorphology disclosed increased pinocytotic activities, subepithelial bleb formation, and degeneration and denudation of the basal lamina. These findings suggest that the increased activities of collagenases in BALF caused by the host response against P. carinii might contribute to leaky alveoli.
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PMID:Collagenases and the serine proteinases elastase and cathepsin G in steroid-induced Pneumocystis carinii pneumonia. 779 Apr 46

Analysis of bovine interphotoreceptor matrix and conditioned medium from human Y-79 retinoblastoma cells by gelatin SDS-PAGE zymography reveals abundant activity of a 72-kDa M(r) gelatinase. The 72-kDa gelatinase from either source is inhibited by EDTA but not aprotinin or NEM, indicating that it is a metalloproteinase (MMP). The 72-kDa MMP is converted to a 62-kDa species with APMA treatment after gelatin sepharose affinity purification, typical of previously described gelatinase MMP-2. The latent 72-kDa gelatinase from either bovine IPM or Y-79 media autoactivates without APMA in the presence of calcium and zinc after 72 hr at 37 degrees C, producing a fully active mixture of proteinase species, 50 (48 in Y-79 medium), 38 and 35 kDa in size. The presence of inhibitory activity was examined in both whole bovine IPM and IPM fractions separated by SDS-PAGE. Whole IPM inhibited gelatinolytic activity of autoactivated Y-79-derived MMP in a dose-dependent manner. Inhibitory activities are observed in two protein fractions of 27-42 and 20-25 kDa. Western blots using antibodies to human tissue inhibitor of metalloproteinase 1 and 2 (TIMP-1 and -2) reveal the presence of two TIMP-1-like proteins at 21 and 29 kDa in inhibitory fractions of the bovine IPM. TIMP-2 was not detected in the inhibitory IPM fractions, consistent with the observed autoactivation of bovine IPM 72-kDa gelatinase. Potential roles for this IPM MMP-TIMP system include physiologic remodelling of the neural retina-RPE cell interface and digestion of shed rod outer segment as well as pathological processes such as retinal detachment, PE cell migration, neovascularization and tumor progression. Cultured Y-79 cells appear to be a good model for studying the production and regulation of this proteinase system.
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PMID:Characterization and novel activation of 72-kDa metalloproteinase in retinal interphotoreceptor matrix and Y-79 cell culture medium. 782 70

We identified a new matrix metalloproteinase (membrane type matrix metalloproteinase (MT-MMP)) that has a potential transmembrane (TM) domain at the C terminus and reported its expression on the surface of invasive tumor cells. The expression of MT-MMP induced specific activation of 72-kDa pro-gelatinase A (Sato, H., Takino, T., Okada, Y., Cao, J., Shinagawa, A., Yamamoto, E., and Seiki, M. (1994) Nature 370, 61-65). Thus, MT-MMP on the cell surface is thought to play an important role in various physiological and pathological processes accompanying tissue remodeling. In this study, we demonstrated that the potential TM domain deduced from the amino acid sequence functions as a membrane linker when it is fused to a secretory protein, tissue inhibitor of matrix metalloproteinases-1. The pro-gelatinase A activation function of MT-MMP was abolished by truncation of the TM domain and recovered by fusing the MT-MMP mutant with the TM domain of interleukin 2 receptor alpha-chain. The truncated MT-MMP was released from the cells into the medium and detected as processed or modified forms. In spite of the deletion of the TM domain some portions of the mutant MT-MMP were still retained on the surface of cells. Thus, MT-MMP has an additional device to keep it on the cell surface. The TM domain however, plays an essential role in the pro-gelatinase A activation function of MT-MMP, probably regulating its fine orientation or the localization that is necessary to interact with substrate.
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PMID:The C-terminal region of membrane type matrix metalloproteinase is a functional transmembrane domain required for pro-gelatinase A activation. 782 14

Immunohistochemical studies of prostate carcinoma reveal that most primary carcinomas, including high-grade tumors, are surrounded by a basal lamina composed of laminin, type IV collagen, and entactin. In addition to the expected laminin subchains A, B1, B2, subchains M and S are also found. Tenascin, found around normal glands, is seen in 60% of carcinomas. The basal cells of the normal gland express several integrin alpha units including alpha 2,3,4,5,6, and v. Both beta 1 and beta 4 subunits are observed. These integrin units are polarized at the base of the cells where they codistribute with the surrounding extracellular matrix. The integrin alpha 6 beta 4 is associated with hemidesmosomal-like structures, as detected by transmission electron microscopy (TEM). In carcinoma, the beta 4 is not observed and the alpha 6 and beta 1 subunits are variably expressed. The integrin expression in carcinoma is diffuse in the cytoplasmic membrane and not restricted to the basal aspects of the cell. In addition, type VII collagen and the BP 180 protein which are associated with hemidesmosomes are lost, although the BP 230, plectin, and HD1 proteins are variably expressed. Using immunohistochemistry and northern analysis we observed three metalloproteinases in prostate carcinoma--matrilysin, gelatinase A, and gelatinase B. Western blotting and zymogram analysis reveal that of these three, only matrilysin appears to be present in its active form. Recent in situ hybridization studies reveal focal expression of the matrilysin mRNA in 25/33 primary carcinomas. Matrilysin also appears to be highly expressed in prostatic ducts and atrophic glands. Expression of the three metalloproteinases is also seen in prostatic intraepithelial neoplasia lesions.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Adhesion molecules, extracellular matrix, and proteases in prostate carcinoma. 782 96


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