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)

The action of three matrix metalloproteinases (MMPs), 72- and 95-kDa gelatinases (MMP-2 and MMP-9) and PUMP (MMP-7), and a cysteine proteinase, cathepsin B, were investigated on aggrecan the major proteoglycan of cartilage. All the enzymes cleaved aggrecan although the activity of the 95-kDa gelatinase was very low. Specific cleavage sites were investigated following incubation with a purified aggrecan G1-G2 domain fragment (150 kDa). Both gelatinases produced 110-kDa G2 and 56-kDa G1 products by a single cleavage at an Asn-Phe bond within the interglobular domain close to the G1 domain. This was similar to the action of stromelysin (MMP-3) (Fosang, A. J., Neame, P. J., Hardingham, T. E., Murphy, G., and Hamilton, J. A. (1991) J. Biol. Chem. 266, 15579-15582). Cathepsin B also produced two fragments from a single cleavage at a Gly-Val bond only three amino acids C-terminal to the metalloproteinase cleavage site. PUMP cleaved at the metalloproteinase Asn-Phe site, but in addition produced a low yield of a smaller G2 fragment (56 kDa) corresponding to cleavage between Asp441 and Leu442 (human sequence), within the interglobular domain, close to the G2 domain. The apparent difference in size between the two G2 fragments released by PUMP (110 and 56 kDa) was much greater than predicted from the peptide length between the cleavage sites (100 amino acids). However, keratanase digestion greatly reduced the size of the 110-kDa G2 fragment, while producing only a small reduction in size of the 56-kDa product, showing that there was approximately 30-40 kDa of keratan sulfate attached to the interglobular domain between the PUMP cleavage sites. This new structural information on aggrecan may account for the previously observed stiffness of the interglobular domains when viewed by rotary shadowing electron microscopy (Paulsson, M., Morgelin, M., Wiedemann, H., Beardmore-Gray, M., Dunham, D. G., Hardingham, T. E., Heinegard, D., Timpl, R., and Engel, J. (1987) Biochem. J. 245, 763-772). These results show that in spite of a high keratan sulfate content the interglobular domain provides important sites for cleavage by different proteinases, including several members of the matrix metalloproteinase family.
J Biol Chem 1992 Sep 25
PMID:The interglobular domain of cartilage aggrecan is cleaved by PUMP, gelatinases, and cathepsin B. 132 52

The latent precursor of matrilysin (EC 3.4.24.23; punctuated metalloproteinase (PUMP) was purified from transfected mouse myeloma cell conditioned medium and was found to contain one zinc atom per molecule which was essential for catalytic activity. Promatrilysin could be activated to the same specific activity by (4-aminophenyl)mercuric acetate, trypsin, and incubation at elevated temperatures (heat activation). Active matrilysin hydrolyzed the fluorescent substrate 2,4-dinitrophenyl-Pro-Leu-Gly-Leu-Trp-Ala-D-Arg-NH2 at the Gly-Leu bond with a maximum value for kcat/Km of 1.3 x 10(4) M-1 s-1 at the pH optimum of 6.5 and pKa values of 4.60 and 8.65. Activity is inhibited by the tissue inhibitor of metalloproteinases-1 in a 1:1 stoichiometric interaction. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis in conjunction with N-terminal sequencing revealed that, as with all other matrix metalloproteinases similarly studied, promatrilysin activation was accompanied by the stepwise proteolytic removal of an M(r) 9000 propeptide from the N-terminus. The intermediates generated were dependent on the mode of activation used but, in all cases studied, activation terminated with an autocatalytic cleavage at E77-Y78 to yield the final M(r) 19,000 active matrilysin. From an analysis of the stability of the various intermediates, we propose that the sequence L13-K33 is particularly important in protecting the E77-Y78 site from autocatalytic cleavage, thereby maintaining the latency of the proenzyme.
Biochemistry 1992 Sep 15
PMID:Biochemical characterization of matrilysin. Activation conforms to the stepwise mechanisms proposed for other matrix metalloproteinases. 139 Jun 35

Numerous studies have reported a correlation between production of 72-kDa (MMP-2) and 92-kDa (MMP-9) type-IV collagenases/gelatinases and the metastatic potential of cancer cells. An abrogating effect of tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) on metastases has also been noted. In this report we have used sensitive enzyme-linked immunoassays to measure MMP-2, MMP-9, TIMP-1 and TIMP-2 levels in eight human lung-cancer cell lines which were characterized for biological behavior in nude mice. We demonstrated that the Calu-6 and A549 cell lines with the highest metastatic, invasive and tumorigenic potential secreted the highest levels of MMP-2. MMP-9 and TIMP-1 secretions were comparatively low in all cell lines. TIMP-2 secretion, which exceeded MMP-2 secretion for all cell lines, did not correlate with metastatic potential. To further explore these correlations, the metastatic Calu-6 cell line was transfected with a K-rev-1 cDNA expression construct. The K-rev revertant cell lines demonstrated a more differentiated phenotype and were less tumorigenic, invasive and metastatic in nude mice. Nonetheless, the Calu-6 revertant cell lines secreted higher levels of MMP-2 than the parent cell line. In conclusion, invasion and metastasis by lung-cancer cells requires not only enhanced MMP production, but also other less well-understood tumorigenic characteristics. The multiplicity of factors required by cancer cells for dissemination helps to explain the minute fraction of cancer cells from a primary tumor that ever develop into a metastasis.
Int J Cancer 1992 Sep 30
PMID:Secretion of gelatinases and tissue inhibitors of metalloproteinases by human lung cancer cell lines and revertant cell lines: not an invariant correlation with metastasis. 139 11

BHAC-MMP therapy, a combination of behenoyl-ara-C, mitoxantrone, 6-mercaptopurine and prednisolone, was applied to 49 patients with acute leukemia for remission induction. Complete remission was obtained in 6 out of 11 previously untreated patients (55%), and in 16 of 38 pretreated patients (42%). Median duration of complete remission was 41 weeks in previously treated patients, while 67% of untreated patients were still in complete remission. Most frequent side effects other than hematological toxicities were gastrointestinal disturbances, and GPT elevation etc., although most of these were not severe. In conclusion, BHAC-MMP therapy seems to be very promising for remission induction or for possible intensification treatment for acute leukemia.
Gan To Kagaku Ryoho 1986 Sep
PMID:[A phase III study of BHAC-MMP (behenoyl-ara-C, mitoxantrone, 6-mercaptopurine prednisolone) in acute leukemia. Hanshin Cooperative Study Group of Hematological Disorders]. 353 Jan 40

Fifteen archival human osteosarcoma specimens were examined by in situ hybridization for the expression of human and mouse transforming growth factor-beta (isoforms 1, 2, and 3), c-fos, and metalloproteinase (stromelysin-3 and matrilysin). Osteosarcoma subtypes were confirmed by review of patients' radiographs, histopathology, and age at diagnosis. The outcome and method of treatment were documented. The subtypes of osteosarcoma consisted of nine conventional osteosarcomas and two each of fibroblastic, telangiectatic, and post-radiation osteosarcomas. Each specimen was histologically examined under light microscopy, and then adjacent paraffin sections were assayed with sense and anti-sense RNA probes by in situ hybridization. The probes localized to the neoplastic cells, confirming the methodology of the technique. Human transforming growth factor-beta 1 had the most uniform binding affinity to the osteosarcomas examined and was more specific in binding than mouse transforming growth factor-beta 1. Specific mRNA encoding for the transforming growth factor-beta s, c-fos, and metalloproteinases are detectable in patterns within osteosarcoma cells, and collectively, their expression parallels the different histopathologic subtypes. The less differentiated subtypes (telangiectatic and post-radiation osteosarcomas) expressed the fewest molecular markers. Osteosarcoma is a heterogeneous tumor. Differential expression of matrilysin in osteosarcoma is the first reported detection of metalloproteinase activity in human skeletal sarcoma.
J Orthop Res 1995 Sep
PMID:Osteosarcoma oncogene expression detected by in situ hybridization. 747 45

In vitro angiogenesis models suggest that new blood vessel formation requires the induction and secretion by endothelial cells of matrix metalloproteinases. These enzymes assist in the controlled proteolytic degradation of the surrounding extracellular matrix during blood vessel formation. The results of in vitro studies cannot be extrapolated directly to the process of in vivo angiogenesis because the type of matrix employed and the repertoire of enzymes secreted by cells in vivo differ dramatically from in vivo conditions. To investigate the in vivo role of matrix metalloproteinases in blood vessel development, we looked for the presence of these proteinases in endothelial cells involved in fetal angiogenesis and in neovascularization of certain invasive skin tumors using immunofluorescent staining. In fetal tissue, interstitial collagenase was present in both early microvessels developing from undifferentiated mesoderm and in microvessels involved in elongation and sprout formation from preexisting blood vessels. In aggressive skin tumors, i.e., morpheaform and recurrent basal cell carcinomas and squamous cell carcinomas, there was a marked increase in the number of collagenase-containing blood vessels, often extending into the tumor nests. Immunofluorescent staining failed to detect stromelysin, matrilysin, or gelatinase A and B (72- and 92-kDa type IV collagenases, respectively) in fetal or tumor blood vessels. These findings are consistent with the hypothesis that proteolytic degradation of the extracellular matrix is required for the formation of new blood vessels. Interstitial collagenase appears to play an important role in this process.
J Invest Dermatol 1995 Sep
PMID:Matrix metalloproteinases in blood vessel development in human fetal skin and in cutaneous tumors. 754 2

Membrane-type matrix metalloproteinase (MT-MMP), which we have identified recently, is unique in its transmembrane (TM) domain at the C terminus and mediates activation of pro-gelatinase A on the cell surface (Sato, H., Takino, T., Okada, Y., Cao, J., Shinagawa, A., Yamamoto, E., and Seiki, M. (1994) Nature 370, 61-65; Takino, T., Sato, H., Yamamoto, E., and Seiki, M. (1995) Gene (Amst.) 115, 293-298). In addition to MT-MMP, a novel MMP-related cDNA of 2.1 kilobases was isolated from a human placenta cDNA library. The cDNA contains an open reading frame for a new MMP. The deduced protein composed of 604 amino acids was closely related to MT-MMP in the amino acid sequence (66% homology at the catalytic domains) and has a potential TM domain at the C terminus. Monoclonal antibodies raised against the synthetic peptide recognized a 64-kDa protein as the major product in the transfected cells. TIMP-1 fused with the potential TM domain was localized on the cell surface while native TIMP-1 is in the culture medium. Thus, we called the second membrane-type MMP, MT-MMP-2 and renamed MT-MMP, MT-MMP-1. MT-MMP-1 and -2 are thought to form a distinct membrane-type subclass in the MMP family since all the others are secreted as soluble forms. Like MT-MMP-1, expression of MT-MMP-2 induced processing of pro-gelatinase A (68-kDa in gelatin zymography) into the activated form of 62-kDa fragments through a 64-kDa intermediate form. Expression of MT-MMP-2 mRNA was at the highest levels in the brain where MT-MMP-1 was at the lowest level compared to other tissues. MT-MMP-1 and -2 are thought to be utilized for extracellular matrix turnover on the surface of cells under different genetic controls.
J Biol Chem 1995 Sep 29
PMID:Identification of the second membrane-type matrix metalloproteinase (MT-MMP-2) gene from a human placenta cDNA library. MT-MMPs form a unique membrane-type subclass in the MMP family. 755 40

The weights of pregnancy-dependent mammary tumors (PDMT) of GR/A mice continued to increase until parturition and decreased soon after delivery; however, mitotic indices in epithelial cells and stromal cells of PDMT reached a maximum plateau on Day 18-19 of pregnancy and decreased thereafter. Growth of PDMT in progesterone-treated mice on Day 15 of pregnancy was higher than that in 17 beta-estradiol-treated mice and no treatment controls. DNA fragmentation was observed in PDMT on Day 20 of pregnancy and just after parturition. Two-dimensional gel electrophoresis of PDMT extracts revealed that five and six protein spots appeared newly on Day 20 of pregnancy and just after parturition, respectively. N-terminal amino acid sequences of two of the protein spots were identical to that of alpha-lactalbumin. PDMT on Day 15 and 20 of pregnancy and just after parturition secreted matrilysin, one of the matrix metalloproteinases, which was identified by Western blotting. However, matrilysin was not found in hormone-independent autonomous mammary tumors of the mouse. Estrogen receptor and c-fos mRNA expression levels in PDMT were high on Day 15 of pregnancy but low on Day 20 of pregnancy and just after parturition. These findings suggest that regression of PDMT is caused by apoptosis, and new proteins expressed on Day 20 may participate in the process of regression.
Proc Soc Exp Biol Med 1995 Sep
PMID:Biochemical changes during growth and regression of pregnancy-dependent mammary tumors of GR/A mice. 763 41

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.
Ann Otol Rhinol Laryngol 1995 Sep
PMID:Analysis of expression of matrix metalloproteinases-2 and -9 in hypopharyngeal squamous cell carcinoma by in situ hybridization. 766 15

The activation of human neutrophil progelatinase B (pro-HNG) by a variety of proteolytic and non-proteolytic activators has been investigated. A quantitative comparison of the activation efficiencies of treatments previously reported to activate pro-HNG or the related gelatinase B species produced by other cells demonstrates that stromelysin and trypsin are good activators. HgCl2 is a moderately effective activator, while p-chloromercuribenzoate and NaOCl are poor activators. It is also shown that human matrilysin and human fibroblast-type collagenase can activate pro-HNG by a mechanism that is very similar to that of stromelysin. Initially, these proteinases hydrolyze the Glu40-Met41 bond in the propeptide domain to generate an 88 kDa inactive HNG species. Collagenase also generates a 68 kDa HNG species through hydrolysis of the Ala74-Met75 bond. Ultimately, treatment with either matrilysin, collagenase or trypsin results in the production of a 65 kDa active form of HNG that arises from hydrolysis of the Arg87-Phe88 bond. This is the same active species produced on activation by stromelysin. This cleavage site is downstream of the 'cysteine-switch' residue located at position 80 and releases it, accounting for the permanent activation of the enzyme. These results suggest that matrilysin and collagenase may be physiologically relevant activators of pro-HNG and/or other progelatinase B species. Activation by HgCl2 produces an active 68 kDa enzyme due to autolytic hydrolysis of the Ala74-Met75 bond. This species retains the cysteine switch residue; however, it is shown that it is only active in the continued presence of HgCl2. Removal of the HgCl2 restores latency, indicating that this species is reversibly activated by HgCl2, which functions by complexing the sulfhydryl group of the cysteine switch residue and keeping it dissociated from the active site zinc atom. Thus, in spite of reports to the contrary, the cysteine switch mechanism can account for the latency and activation of pro-HNG.
Biochim Biophys Acta 1995 Sep 06
PMID:Proteolytic and non-proteolytic activation of human neutrophil progelatinase B. 766 17


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