Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.35 (matrix metalloproteinase 9)
 2,207 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The precursor of matrix metalloproteinase 9 (proMMP-9), also known as '92 kDa progelatinase/type IV procollagenase', was purified from the conditioned medium of U937 monocytic leukaemia and HT1080 fibrosarcoma cell lines stimulated with phorbol 12-myristate 13-acetate. ProMMP-9 in these culture media is non-covalently complexed with the 29 kDa tissue inhibitor of metalloproteinases (TIMP), but free proMMP-9 was separated from the TIMP-proMMP-9 complex by chromatography on Green A Dyematrex gel. The final product was homogeneous on SDS/PAGE, with a molecular mass of 88 kDa without reduction and 92 kDa with reduction. Treatment of proMMP-9 with 4-aminophenylmercuric acetate converted the 88 kDa precursor into 80 kDa and 68 kDa forms. Gelatin-containing zymographic analysis showed zones of lysis associated with all three species. However, only the 68 kDa species was shown to be catalytically active by its ability to bind to alpha 2-macroglobulin. In the presence of an equimolar amount of TIMP, only the 80 kDa species was generated by treatment with 4-aminophenylmercuric acetate, but no enzyme activity was detected. This indicates that TIMP binds to the 80 kDa intermediate and inhibits the generation of the active 68 kDa species. Eight endopeptidases (trypsin, chymotrypsin, plasmin, plasma kallikrein, thrombin, cathepsin G, neutrophil elastase and thermolysin) were tested for their ability to activate proMMP-9. Of them, trypsin was the most effective activator of proMMP-9. Only partial activation (10-30%) was observed with plasmin, cathepsin G and chymotrypsin. The active forms generated by trypsin were identified as 80 kDa, 74 kDa and 66 kDa by their abilities to bind to alpha 2-macroglobulin. In the presence of an equimolar amount of TIMP, proMMP-9 was also converted into the same molecular-mass species by trypsin, but they were not proteolytically active. This suggests activated MMP-9 is inhibited by TIMP. Activated MMP-9 digested gelatin, type-V collagen, reduced carboxymethylated transferrin and, to a lesser extent, type-IV collagen and laminin A chain. The specific activity against gelatin was estimated to be 15,000 units/mg (1 unit = 1 microgram of gelatin degraded/min at 37 degrees C) by titration with alpha 2-macroglobulin. Comparative studies on digestion of gelatin and collagen types IV and V by MMP-9 and MMP-2 indicated that both enzymes degrade these substrates into similar fragments. However, the susceptibilities of laminin, fibronectin and reduced carboxymethylated transferrin to these two MMPs were sufficiently different to indicate differences in substrate specificities between these two closely related proteinases.
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PMID:Purification and characterization of matrix metalloproteinase 9 from U937 monocytic leukaemia and HT1080 fibrosarcoma cells. 137 48

Matrix metalloproteinase 9 (MMP-9) has been purified as an inactive zymogen of M(r) 92,000 (proMMP-9) from the culture medium of HT 1080 human fibrosarcoma cells. The NH2-terminal sequence of proMMP-9 is Ala-Pro-Arg-Gln-Arg-Gln-Ser-Thr-Leu-Val-Leu-Phe-Pro, which is identical to that of the 92-kDa type IV collagenase/gelatinase. The zymogen can be activated by 4-aminophenylmercuric acetate, yielding an intermediate form of M(r) 83,000 and an active species of M(r) 67,000, the second of which has a new NH2 terminus of Met-Arg-Thr-Pro-Arg-(Cys)-Gly-Val-Pro-Asp-Leu-Gly-Arg-Phe-Gln-Thr- Phe-Glu. Immunoblot analyses demonstrate that this activation process is achieved by sequential processing of both NH2- and COOH-terminal peptides. TIMP-1 complexed with proMMP-9 inhibits the conversion of the intermediate form to the active species of M(r) 67,000. The proenzyme is fully activated by cathepsin G, trypsin, alpha-chymotrypsin, and MMP-3 (stromelysin 1) but not by plasmin, leukocyte elastase, plasma kallikrein, thrombin, or MMP-1 (tissue collagenase). During the activation by MMP-3, proMMP-9 is converted to an active species of M(r) 64,000 that lacks both NH2- and COOH-terminal peptides. In addition, HOCl partially activates the zymogen by reacting with an intermediate species of M(r) 83,000. The enzyme degrades type I gelatin rapidly and also cleaves native collagens including alpha 2 chain of type I collagen, collagen types III, IV, and V at undenaturing temperatures. These results indicate that MMP-9 has different activation mechanisms and substrate specificity from those of MMP-2 (72-kDa gelatinase/type IV collagenase).
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PMID:Matrix metalloproteinase 9 (92-kDa gelatinase/type IV collagenase) from HT 1080 human fibrosarcoma cells. Purification and activation of the precursor and enzymic properties. 140 Apr 81

The ability of normal rabbit dermal fibroblasts to degrade films of type IV collagen and gelatin when stimulated by phorbol ester was shown to be dependent on the induction, secretion and activation of 95 kDa gelatinase B and the secretion and activation of 72 kDa gelatinase A and stromelysin. Degradation was inhibited by exogenous human recombinant tissue inhibitor of metalloproteinases-1, specific antibodies to gelatinase and stromelysin and by the reactive-oxygen-metabolite inhibitor catalase. We discuss the various pathways for activation of matrix metalloproteinases in this model system and conclude that, although plasmin may play a key role in the activation of gelatinase B and stromelysin, gelatinase A is activated by a mechanism which has yet to be elucidated. The involvement of oxygen radicals in the direct activation of matrix metalloproteinases in this model is thought to be unlikely.
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PMID:Cell-mediated degradation of type IV collagen and gelatin films is dependent on the activation of matrix metalloproteinases. 146 64

The capacity of solid tumours to invade the surrounding tissue and to metastasize, is correlated with the formation and degradation of structural elements in the vicinity of the tumour cells. Substances with both procoagulant activity and fibrinolytic activity are important factors in the formation or degradation of a "fibrin-fibronectin-gel matrix". This gel is subsequently transformed into the extracellular matrix, which, together with cells, will form the tumour stroma. When analyzing tumour stroma degradation products, it is obvious that the protease plasmin catalyses the disintegration of fibrin and fibronectin. Additional compounds of the tumour stroma and of the basal membrane are also, at least in part, broken down by plasmin or other proteases, such as collagenase IV and cathepsin D. The plasminogen activator urokinase (uPA) seems to play a central role as it was shown that elevated content of uPA is correlated with a high risk of early relapse and shorter overall survival, at least in breast cancer. It has been shown, that by means of quantifying uPA, patients with a relative high or low risk can even be selected within the classical risk groups, which so far are defined by the locoregional extension of the tumour and the hormone receptor status only. Evidently, as uPA content in human breast cancer tissue is an independent prognostic factor, one may speculate, that those experimental or in vitro data, which correlated increase in uPA-synthesis with malignancy, may be of direct relevance for human tumour biology. Moreover, due to these recent observations on the prognostic significance of tumour-associated proteases, new aspects for the selection of risk collectives within the node-negative breast cancer patients for adjuvant therapy have to be considered. It may well be possible, that one may affect tumour invasion and metastasis by inhibiting protease action of solid tumours by disturbing the binding of proteases to tumour cell surface receptors. As it is only a quantitative aspect, which separates benign physiological processes from tumour cell pathophysiology, experimental evidence suggests, that less drastic forms of palliative therapy can be proposed.
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PMID:[Clinical and prognostic significance of tumor-associated proteases in gynecologic oncology]. 204 Apr 18

Prognostic variables in breast cancer are urgently needed to individualize adjuvant cytotoxic therapy, especially in those patients where metastases in the lymph nodes have not been detected (node-negative disease). So far histomorphological criteria, the determination of receptors for steroid hormones or EGF (epidermal growth factor), the protease cathepsin D or DNA-ploidy are used to distinguish between low- and high-risk patients. High-risk patients have a higher incidence of recurrences and/or shorter overall survival after surgery of the primary tumour than low-risk patients. High-risk patients (node-positive; hormone-receptor-negative) would receive adjuvant hormone therapy or chemotherapy. In the node-negative patient, adjuvant therapy is only recommended if a high content of cathepsin D and aneuploidy of the tumour (or high S-phase in diploid tumours) has been diagnosed. Determination of cathepsin D in tumour extracts as a variable in breast cancer patients is based on the fact that invasion and metastasis is correlated with elevated levels of tumour-associated proteases such as cathepsins B and D, collagenase IV and plasminogen activators. The urokinase-type plasminogen activator (uPA) which is secreted by tumour cells as an enzymatically inactive proenzyme (pro-uPA) seems to play a key role in mediating tumour cell invasion in cancer tissues. Receptor-bound uPA converts enzymatically inactive plasminogen into the serine protease plasmin which then degrades the extracellular matrix surrounding the tumour cells (tumour stroma). We localized pro-uPA/uPA immunohistochemically in paraffin-embedded formalin-fixed breast cancer tissue sections. Pro-uPA/uPA was detected in the cytoplasm and on the plasma membrane of the tumour cells reflecting receptor-bound pro-uPA/uPA.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Tumour-associated fibrinolysis: the prognostic relevance of plasminogen activators uPA and tPA in human breast cancer. 213 50

The precursor of matrix metalloproteinase 9 (pro-MMP-9) forms a complex with the tissue inhibitor of metalloproteinases (TIMP)-1 through the C-terminal domain of each molecule, and the N-terminal domain of TIMP-1 in the complex interacts and inhibits active MMPs. We have reported that a catalytic amount of MMP-3 (stromelysin 1) activates pro-MMP-9 (Ogata, Y., Enghild, J. J., and Nagase, H. (1992) J. Biol. Chem. 267, 3581-3584). To activate pro-MMP-9 in the complex, however, an excess molar amount of MMP-3 is required to saturate the TIMP-1 in the complex. The aim of this study was to test the hypothesis that the requirement for excess MMP-3 can be circumvented by specific destruction of TIMP-1 by non-target proteinases. We have tested trypsin, plasmin, cathepsin G, neutrophil elastase, and chymotrypsin as possible inactivators of TIMP-1 and found that neutrophil elastase inactivates TIMP-1 in the complex without significant destruction of pro-MMP-9. Once TIMP-1 is inactivated, pro-MMP-9 can be readily activated by a catalytic amount of MMP-3. These results suggest that neutrophil elastase may participate in the connective tissue destruction at the inflammatory sites not only by its direct action on matrix macromolecules but also by rendering pro-MMP-9 in the pro-MMP-9.TIMP-1 complex activable by MMP-3 as well as activating pro-MMP-3.
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PMID:Preferential inactivation of tissue inhibitor of metalloproteinases-1 that is bound to the precursor of matrix metalloproteinase 9 (progelatinase B) by human neutrophil elastase. 762 55

Matrix metalloproteinase 7 (MMP-7) has been purified as an inactive zymogen of M(r) 28,000 (proMMP-7) from the culture medium of CaR-1 human rectal carcinoma cells. The NH2-terminal sequence of proMMP-7 is Lys-Pro-Lys-Pro-Gln-Glu, which is identical to that of matrilysin. The zymogen is activated by 4-aminophenylmercuric acetate (APMA), yielding an intermediate form of M(r) 21,000 and an active species of M(r) 19,000 which shows the new NH2-terminal sequence of Tyr78-Ser-Leu-Phe-Pro-Asn-Ser. Although trypsin fully activates the zymogen, the activation rate by plasmin or leukocyte elastase is confined to approximately 50%. ProMMP-7 can be activated by MMP-3 (stromelysin 1) to its full activity in a single-step mechanism and generates the same NH2 terminus obtained by APMA activation, whereas MMP-1 (tissue collagenase), MMP-2 (gelatinase A), and MMP-9 (gelatinase B) do not have such an effect. On the other hand, proMMP-1 is activated by MMP-7 to an activity similar to that obtained by APMA and the activation by MMP-7 is enhanced up to approximately 6.5 fold in the presence of APMA. This enhanced activity is donated by specific cleavage at the Gln80-Phe81 bond of proMMP-1. MMP-7 can also activate proMMP-9 up to approximately 50% of the full activity with a new NH2 terminus of Leu16-Arg-Thr-(Asn)-Leu. Incubation of proMMP-2 or proMMP-3 with MMP-7 results in no activation of these proMMPs. MMP-7 degrades type IV collagen, laminin-1, fibronectin, proteoglycan, type I gelatin, and insoluble elastin. These results suggest that in vivo MMP-7 may play a role in degradation of extracellular matrix macromolecules in concert with MMP-1, -3, and -9 under pathological conditions.
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PMID:Matrix metalloproteinase 7 (matrilysin) from human rectal carcinoma cells. Activation of the precursor, interaction with other matrix metalloproteinases and enzymic properties. 789 11

Serine proteases and matrix metalloproteinases have been shown to often cooperate in multiple physiological and pathological processes associated with changes in the extracellular matrix (ECM). We have examined the interaction between the plasminogen activator (PA)-plasmin system and matrix metalloproteinases (MMPs) in HT1080 human fibrosarcoma cells treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA). While TPA treatment evoked a temporary increased expression of urokinase type PA (uPA), the production of both types of human plasminogen activator inhibitors (PAI) was induced and sustained over 12 h by TPA treatment shifting the protease-protease inhibitors balance in favor of the inhibitors. TPA treatment of HT1080 cells induced the expression of interstitial collagenase (MMP-1) and increased the expression of gelatinase B (MMP-9), tissue inhibitor of metalloproteinases-1 (TIMP-1), and MT-MMP, a membrane-bound activator of progelatinase A (proMMP-2), while MMP-2 and TIMP-2 expression were decreased. Increased MT-MMP expression by TPA treatment was associated with increased activation of proMMP-2. These data show that the regulation of PA-plasmin and metalloproteinase and their specific inhibitors is uncoordinated. In addition, inhibition of the PA-plasmin system by PAI-2 or aprotinin did not prevent the activation of proMMP-2 by TPA, suggesting that plasmin is not involved in MT-MMP-mediated activation of proMMP-2.
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PMID:Independent regulation of matrix metalloproteinases and plasminogen activators in human fibrosarcoma cells. 861 75

Human heart matrix metalloproteinases (MMP) are present in the latent form and activated in the failing heart. To examine whether the MMP activation was due to gene and/or post-translational modification, we analysed tissue from 10 explanted hearts due to coronary heart disease (CHD) and five normal left atrial tissue from donor hearts. Based on in situ immunolabeling MMP-1, tissue inhibitor of metalloproteinase (TIMP-1) and collagen were co-localized in the interstitial tissue. Based on sandwich ELISA, TIMP-1 and MMP-1 levels were 37 +/- 8 ng/mg and 9 +/- 2 ng/mg in normal tissue (P < 0.01) and 12 +/- 5 ng/mg and 75 +/- 11 ng/mg in the infarcted tissue (P < 0.01), respectively. These levels suggest repression of TIMP-1 during myocardial infarction. Northern blot analysis indicated that the mRNAs for both MMP-1 and TIMP-1 were increased three-to four-fold in the infarcted tissue as compared to the normal tissue, suggesting upregulation of MMP and TIMP gene transcription following infarction. Based on in situ tissue overlay zymography, the generalized activation of MMP was observed in the interstitium of the infarcted heart. Zymographic and immunoblot analysis demonstrated the presence of one band at 66 kDa (MMP-2) in the normal tissue and several bands at 92 (MMP-9), 66 (MMP-2) and 54 kDa (MMP-1) in the infarcted heart. Incubation of the zymographic gel with metal chelator (phenanthroline) abolished bands at 92 kDa and 54 kDa but phenanthroline did not abolish the lytic band at 66 kDa. The 66 kDa band was completely abolished in the presence of phenanthroline and phenyl methyl sulfonyl fluoride (PMSF). 2D-zymographic analysis suggested that the lytic band at 66 kDa was a mixture of two neutral proteinases with different isoelectric point. Plasminogen/gelatin zymographic analysis of infarcted tissue extract indicated that the band at 66 kDa was plasmin generated due to increased expression of tissue plasminogen activator (tPA) activity. In relation to increased expression of gelatinase in the infarcted tissue, our data suggest that gelatinase B (92 kDa) is induced in diseased heart. The results suggest that tPA converts plasminogen to plasmin which, in turn, activates MMPs and inactivates TIMP-1 post-translationally following ischemic cardiomyopathy.
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PMID:Post-transcriptional regulation of extracellular matrix metalloproteinase in human heart end-stage failure secondary to ischemic cardiomyopathy. 884 29

Membrane vesicles are shed by tumor cells both in vivo and in vitro. Although their functions are not well understood, it has been proposed that they may play multiple roles in tumor progression. We characterized membrane vesicles from human HT1080 fibrosarcoma cell cultures for the presence of proteinases involved in tumor invasion. By gelatin zymography and Western blotting, these vesicles showed major bands corresponding to the zymogen and active forms of gelatinase B (MMP-9) and gelatinase A (MMP-2) and to the MMP-9. tissue inhibitor of metalloproteinase 1 complex. Both gelatinases appeared to be associated with the vesicle membrane. HT1080 cell vesicles also showed a strong, plasminogen-dependent fibrinolytic activity in 125I fibrin assays; this activity was associated with urokinase plasminogen activator, as shown by casein zymography and Western blotting. Urokinase was bound to its high affinity receptor on the vesicle membrane. Addition of plasminogen resulted in activation of the progelatinases associated with the vesicles, indicating a role of the urokinase-plasmin system in MMP-2 and MMP-9 activation. We propose that vesicles shed by tumor cells may provide a large membrane surface for the activation of membrane-associated proteinases involved in extracellular matrix degradation and tissue invasion.
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PMID:Urokinase plasminogen activator and gelatinases are associated with membrane vesicles shed by human HT1080 fibrosarcoma cells. 920 45


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