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)

Interstitial collagenase (EC 3.4.24.7, matrix metalloproteinase-1, MMP-1) is synthesized and secreted by many cells, and plays an important role in a wide variety of pathophysiological degradation processes of extracellular matrices. The activity of MMP-1 is regulated by tissue inhibitors of metalloproteinases, TIMP-1 or TIMP-2, which form a non-covalent complex with the active enzyme. We raised monoclonal antibodies against zymogen of MMP-1, proMMP-1 purified from human skin fibroblasts. The antibodies recognized both precursor and active forms of MMP-1, but did not cross-react with 72-kDa and 92-kDa gelatinase/type IV collagenases or stromelysin-1. A specific and sensitive one-step sandwich enzyme immunoassay for human MMP-1 was developed using a solid phase monoclonal antibody and a horseradish peroxidase-labeled monoclonal antibody (Fab'). The assay can be completed within 1 h (30 min for immunoreaction and 15 min for color development) and the sensitivity is 0.12 microgram/l with the linearity between 0.12 and 10 micrograms/l. Active MMP-1 shows 1.3-fold higher absorption at 492 nm than proMMP-1. However, the recognition rate of MMP-1 is decreased to approximately 50% and < 3% for the MMP-1-TIMP-1 and MMP-1-TIMP-2 complex forms, respectively. The MMP-1 levels in human sera from 120 healthy subjects are shown to be in the range of 8.5 +/- 5.2 micrograms/l (mean +/- S.D.) and the levels of 95% of the samples range from 0 to 20 micrograms/l.
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PMID:A one-step sandwich enzyme immunoassay for human matrix metalloproteinase 1 (interstitial collagenase) using monoclonal antibodies. 830 49

Human 72-kDa type IV collagenase (72T4Cl) is secreted as a proenzyme that can form a specific stoichiometric complex with the tissue inhibitor of metalloproteases TIMP-2 via interaction with the carboxyl-terminal domain of the enzyme. Both complexed and free enzymes can be activated by treatment with organomercurials. The mechanism of the 72T4Cl activation under physiological conditions is not known. Here we describe a "plasma membrane-dependent" activation of inhibitor-free 72T4Cl and identify the first conversion intermediate as a 64-kDa species resulting from cleavage of the Asn37-Leu peptide bond in the presence of plasma membranes from 12-O-tetradecanoylphorbol-13-acetate-induced HT1080 cells. This reaction is specific for 72T4Cl in that a closely related proenzyme (92-kDa type IV collagenase) is resistant to activation under the same conditions. Formation of the 72T4Cl.TIMP-2 complex inhibits activation at the level of the initial Asn37-Leu cleavage. Addition of TIMP-1 has no effect on this reaction, but blocks the autocatalytic conversion of the Leu38 intermediate into a 62-kDa active enzyme with an amino-terminal Tyr81. Membrane-dependent activation of 72T4Cl is competitively inhibited in the presence of a 26-kDa peptide derived from the carboxyl-terminal domain of the enzyme. The results suggest that interaction of the carboxyl-terminal domain of the enzyme with a membrane-associated component(s) causes initiation of enzyme activation through an autoproteolytic mechanism.
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PMID:Plasma membrane-dependent activation of the 72-kDa type IV collagenase is prevented by complex formation with TIMP-2. 831 71

Tissue-specific localization of HIV-1-infected lymphoid cells may contribute to clinical manifestations of AIDS. Therefore we investigated the effect of HIV-1 infection on mechanisms of T lymphocyte invasion, a process required for movement of cells into and out of the circulation. In the present study, we demonstrate that HIV-1-infected human lymphocytes secrete increased amounts of the human 92-kDa type IV collagenase when compared to uninfected lymphocytes. Furthermore, HIV-1-infected lymphocytes degrade the extracellular matrix proteins collagen IV and fibronectin, and they are more invasive through a reconstituted basement membrane when compared to uninfected cells. The addition of either antibody to the 92-kDa collagenase or TIMP-2, a type IV collagenase inhibitor, abolishes invasive activity. These data suggest that HIV-1-infected lymphocytes express phenotypic characteristics that are consistent with an enhanced ability to leave the circulation and to localize in target tissues. Local viral infection or the release of viral proteins, cytokines, or proteolytic enzymes in tissues may contribute to pathogenesis.
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PMID:HIV-1 infection stimulates T cell invasiveness and synthesis of the 92-kDa type IV collagenase. 834 96

Forty-two cases of malignant lymphomas were studied for the expression of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) by Northern blot and in situ hybridization. The lymphomas were classified according to Working Formulation classification (25 high grade, 15 low grade, and 2 intermediate grade). The MMPs studied included: 72-kDa and 92-kDa gelatinases (type IV collagenases), interstitial collagenase, PUMP-1 (MMP-7), and stromelysins 1 and 3. TIMPs included TIMP-1 and TIMP-2. All but one case expressed TIMP-1, and TIMP-2 transcripts were detected in 35 cases. Among the MMPs, 92-kDa gelatinase was expressed most consistently (35 cases), whereas mRNA transcripts of 72-kDa gelatinase, interstitial collagenase, and PUMP-1 were detected in only a few cases. Stromelysins 1 and 3 mRNAs were not detected in any of the tumors studied. However, marked differences in the level of expression of certain MMPs and TIMPs were found among different grades of malignant lymphomas. The low grade tumors expressed low and relatively constant levels of TIMP-1, TIMP-2, and 92-kDa gelatinase transcripts, whereas high grade lymphomas displayed variable amounts of mRNAs for TIMPs and MMPs, with a trend toward elevated TIMP-1 and 92-kDa gelatinase mRNA levels. In situ hybridization localized TIMP-1 transcripts to stromal cells, while 92-kDa gelatinase transcripts were most abundant in "starry sky" macrophages and large lymphoma cells. Zymography showed that active 92-kDa gelatinase is present in tumor protein extracts and differences in the level of the enzymatic activity were seen between low and high grade lymphomas. Our data indicate that 92-kDa gelatinase and TIMP-1 expression by human malignant lymphomas may play an important role in controlling their biologic aggressiveness.
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PMID:Patterns of expression of metalloproteinases and their inhibitors in human malignant lymphomas. 836 72

We have previously shown that a 78-kDa "invasion stimulating factor" (ISF) triggers collagenase IV (MMP-2) secretion and the invasive behavior of metastatic PC-3 ML subclones in modified Boyden chamber assays [Stearns, M. E.; Stearns, M. Autocrine factors, type IV collagenase secretion and prostatic cancer cell invasion. Cancer Metastasis Rev. 12:39-52; 1993. Wang, M.; Stearns, M.; Stearns, M. E. Identification of the receptor for a novel M(r) 78,000 "invasion stimulating factor" from metastatic human prostatic PC-3 ML clones. Cancer Res. 54:2492-2495; 1994.]. Recently, we have shown that interleukin 10 (IL-10) preferentially stimulates tissue inhibitor of metalloproteinase-1 (TIMP-1) production in these cells [Wang, M.; Stearns, M. E. Characterization of a novel TIMP-1 enhancer element. J. Biol. Chem., submitted.]. In this paper, we report that IL-10 (20-40 ng) can inhibit the invasion stimulatory effects of ISF (30-60 ng) on PC-3 ML cells. "Checkerboard analysis" with modified Boyden chambers (precoated with 10 and 100 micrograms collagen IV) shows that IL-10 inhibits the stimulatory effects of ISF on both cell motility and chemoinvasion processes. In support of these data, exogenously supplied TIMP-1 (10 micrograms/ml) and collagenase antibodies (1:200 dilution) both completely blocked invasion. Quantitative ELISAs comparing the molar ratios of TIMP-1:MMP-2 and TIMP-2:MMP-2 further demonstrate that IL-10 (10-40 ng) preferentially activates TIMP-1 secretion to increase the molar ratio of TIMP-1:MMP-2 in the presence of increasing amounts of ISF (0-60 ng). IL-10 did not elevate TIMP-2 secretion or influence the molar ratio of TIMP-2:MMP-2.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:IL-10 blocks collagen IV invasion by "invasion stimulating factor" activated PC-3 ML cells: upregulation of TIMP-1 expression. 855 49

We examined the production and tissue localization of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in gastric carcinoma tissues. MMP-1 (tissue collagenase), MMP-9 (gelatinase B) and TIMP-2 were immunolocalized in carcinoma cells and MMP-2 (gelatinase A) on tumor cell membranes, whereas no or little immunostaining for MMP-3 (stromelysin-1) and TIMP-1 was seen in carcinoma cells. Stromal cells in carcinoma tissue were also positively stained for these MMPs and TIMPs. MMP-2 immunostaining was observed exclusively on advanced gastric carcinoma cells and correlated with vascular invasion by tumor cells. Sandwich enzyme immunoassays revealed enhanced production of MMP-1, MMP-2, MMP-3, MMP-9 and TIMP-1 by carcinoma tissues. Gelatinolytic activities were significantly higher in carcinoma samples than in normal controls. Using gelatin zymography, active forms of MMP-2 and MMP-9 were more frequently detected in carcinoma tissue, and the activation rate of the zymogen of MMP-2 (proMMP-2), but not that of proMMP-9, correlated well with degree of local invasion and lymphatic permeation. Our data indicate an enhanced production of 4 MMPs in gastric carcinoma tissue and suggest that activation of pro-MMP-2 may be a key step for spreading of gastric carcinoma cells.
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PMID:Enhanced production of matrix metalloproteinases and activation of matrix metalloproteinase 2 (gelatinase A) in human gastric carcinomas. 860 68

The matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) have been associated with tumor invasion and metastasis in many human cancers. Immunohistochemical studies were performed on frozen tumor samples from 42 patients with invasive bladder cancer treated by cystectomy with monoclonal antibodies against the Mr 72,000 gelatinase A (MMP-2), Mr 92,000 gelatinase B (MMP-9), and TIMP-2 to evaluate their significance in bladder cancer. Immunoreactivity for the gelatinases was predominantly tumor cell-associated, whereas strong TIMP-2 staining was mostly detected in the stroma. Tumor cells demonstrated moderate to strong reactivity for MMP-2 and MMP-9 in 71 and 71% of cases, respectively, which did not correlate with stage, grade, or outcome. Tumor cells were positive for TIMP-2 in 26 (62%) of 42 cases, and this correlated with a worse outcome (69 versus 25% died of disease; P < 0.05). In 31 (74%) of 42, there was moderate to strong stromal staining for TIMP-2; this also was associated with a poor outcome (65 versus 25% died of cancer; P < 0.05). Tumor basement membrane (BM) status was investigated using an antibody to type IV collagen. In 9 cases, the invasive tumor nests were surrounded by an intact BM; in 7 of these, stromal staining for TIMP-2 was absent. None of these 9 patients (0%) died of tumors compared with 7 (100%) of 7 with complete loss of BM staining (P < 0.001). These results suggest a potential role for TIMP-2 and BM staining as prognostic indicators in invasive bladder cancer.
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PMID:High levels of tissue inhibitor of metalloproteinase-2 (TIMP-2) expression are associated with poor outcome in invasive bladder cancer. 860 16

Co-cultures of human osteosarcoma Takase (OST) cells with various human fibroblasts derived from surgical specimens stimulated production of gelatinase B (92-kDa type-IV collagenase, MMP-9), tissue inhibitors of metalloproteinase (TIMP)-1, and TIMP-2 when compared to cultures of individual cells. The maximum stimulation of gelatinase-B production occurred at a cellular ratio of 1:1. Conditioned media from several fibroblast cultures stimulated OST cells to produce gelatinase B, TIMP-1 and TIMP-2, but not vice versa. Among various recombinant growth factors or cytokines, tumor necrosis factor (TNF)-alpha stimulated gelatinase-B production in cultures of OST cells alone, while recombinant basic fibroblast growth factor (bFGF) stimulated gelatinase-B production in co-cultures of OST cells with skin fibroblasts but not in individual cultures of each cell type. In the co-cultures, gelatinase-B production was inhibited by anti-bFGF monoclonal antibody (MAb), but not by anti TNF-alpha MAb. This co-culture-specific stimulation of gelatinase-B production by bFGF was associated with increased expression of the FGF receptor in the co-culture.
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PMID:Stimulation of gelatinase B and tissue inhibitors of metalloproteinase (TIMP) production in co-culture of human osteosarcoma cells and human fibroblasts: gelatinase B production was stimulated via up-regulation of fibroblast growth factor (FGF) receptor. 860 72

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

We examined the anti-invasive activity of ursolic acid (UA) on the highly metastatic HT1080 human fibrosarcoma cell line. UA reduced tumor cell invasion through a reconstituted basement membrane in a transwell chamber. A significant down-regulation of matrix metalloproteinase-9 [MMP-9; Mr 92,000 gelatinase/type IV collagenase (gelatinase B)] by UA was detected by Northern blot analysis. However, MMP-2 [Mr 72,000 gelatinase/type IV collagenase (gelatinase A)] and membrane-type MMP were constantly expressed, and the expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 also was not changed after 3 and 6 days of treatment with UA. Quantitative gelatin-based zymography confirmed a markedly reduced expression of MMP-9 but not MMP-2 after treatment with UA. To confirm the UA-induced down-regulation of MMP-9 expression, we constructed a secreted alkaline phosphatase (SEAP) reporter vector including MMP-9 promoter. After transfection of MMP-9/SEAP reporter vector into HT1080 cells, reduced SEAP activity was detected after treatment with UA. These results suggest that down-regulation of MMP-9 contributes to the anti-invasive activity of UA in HT1080 cells.
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PMID:Anti-invasive activity of ursolic acid correlates with the reduced expression of matrix metalloproteinase-9 (MMP-9) in HT1080 human fibrosarcoma cells. 862 99


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