Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The gelatinolytic activity of human skin fibroblast collagenase was examined on denatured collagen types I-V. All denatured substrates were cleaved, including types IV and V, which are resistant to collagenase in native form. Interestingly, the earliest major cleavage in denatured collagen types I-III occurred at a 3/4-1/4 locus, resulting in products electrophoretically identical with TCA and TCB fragments of mammalian collagenase action on these native collagens. However, in the denatured substrates, multiple additional proteolytic cleavages followed. The propensity for cleavage at a 3/4-1/4 site in denatured collagen, where sequence is the major specifier of enzymatic action, would seem to indicate that the most favorable amino acid sequence of gamma chains for catalysis is located in this region. The peptide bond specificity of human fibroblast collagenase on gelatin was examined by amino acid sequencing of extensively cleaved denatured type I collagen. Analysis of the NH2-terminal amino acid residues from the resultant gelatin peptides showed sequences of "-H2N-Ile-Y-Gly" and "H2N-Leu-Y-Gly" only (where Y indicates that any amino acid can be found in that position), indicating that Gly-Ile and Gly-Leu bonds are the only sites of collagenase cleavage in this substrate. Whereas the gamma1 chains of denatured collagen types I-III were cleaved at similar rates, fibroblast collagenase was a much better gamma2-gelatinase than gamm1-gelatinase on denatured type 1 collagen. This preference for the cleavage of gamma2(I) was the result of both a higher kcat (750 versus 230 h-1) and lower Km (3.7 versus 7.0 microM) than for a gamma1(1), resulting in an overall selectivity (kcat/Km) of greater than 6-fold. Compared to such kinetic parameters on native collagen, these values indicate that gelatinolysis is somewhat slower than collagenolysis.
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PMID:The gelatinolytic activity of human skin fibroblast collagenase. 628 90

Explant cultures of adult human trabecular bone fragments give rise to osteoblastic cells, that are known to express osteoblast-related genes and mineralize extracellular matrix. These osteoblastic cells have also been shown to undergo adipogenesis in vitro and chondrogenesis in vivo. Here we report the in vitro developmental potential of adult human osteoblastic cells (hOB) derived from explant cultures of collagenase-pretreated trabecular bone fragments. In addition to osteogenic and adipogenic differentiation, these cells are capable of chondrogenic differentiation in vitro in a manner similar to adult human bone marrow-derived mesenchymal progenitor cells. High-density pellet cultures of hOB maintained in chemically defined serum-free medium, supplemented with transforming growth factor-beta1, were composed of morphologically distinct, chondrocyte-like cells expressing mRNA transcripts of collagen types II, IX and X, and aggrecan. The cells within the high-density pellet cultures were surrounded by a sulfated proteoglycan-rich extracellular matrix that immunostained for collagen type II and proteoglycan link protein. Osteogenic differentiation of hOB was verified by an increased number of alkaline phosphatase-positive cells, that expressed osteoblast-related transcripts such as alkaline phosphatase, collagen type I, osteopontin and osteocalcin, and formed mineralized matrix in monolayer cultures treated with ascorbate, beta-glycerophosphate, and bone morphogenetic protein-2. Adipogenic differentiation of hOB was determined by the appearance of intracellular lipid droplets, and expression of adipocyte-specific genes, such as lipoprotein lipase and peroxisome proliferator-activated receptor gamma2, in monolayer cultures treated with dexamethasone, indomethacin, insulin and 3-isobutyl-1-methylxanthine. Taken together, these results show that cells derived from collagenase-treated adult human trabecular bone fragments have the potential to differentiate into multiple mesenchymal lineages in vitro, indicating their developmental plasticity and suggesting their mesenchymal progenitor nature.
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PMID:Multilineage mesenchymal differentiation potential of human trabecular bone-derived cells. 1238 74

Laminin-5 (LN-5) is an important epithelial cell-derived structural and adhesive component in hemidesmosomes and basement membranes (BM). In peri-implant tissue, gingival BM underlies the junctional epithelium (JE) and reflects the peri-implant health. Matrix metalloproteinase-8 (MMP-8 or collagenase-2) is one of the key mediators of periodontal tissue destruction. Western immunoblotting with image analysis was used to quantitate the molecular forms of LN-5 gamma2-chain and MMP-8 in peri-implant sulcular fluid (PISF) from healthy and diseased implants. These observations were related to the recorded gingival (GI) and bone resorption (BR) indices of the studied sites. Altogether, 72 PISF samples from osseointegrated dental implants were examined. Significantly elevated levels of fragmented LN-5 gamma2-chain species (45 and 70 kDa) and MMP-8 immunoreactivities were observed in diseased PISF in relation to healthy PISF. The elevated levels of both LN-5 gamma2-chain 45 and 70 kDa fragments and MMP-8 in diseased PISF from peri-mucositis (BR = 0) and peri-implantitis (BR >/= 1) lesions strongly correlated with elevated GI. Low levels - almost comparable to those seen in healthy control PISF - were seen in PISF from peri-implantitis lesions (BR >/= 1) with no GI. Activation of 75 kDa neutrophil (PMN)-type proMMP-8 to 10 kDa lower-molecular-size active forms was especially detected in PISF from peri-implantitis with elevated GI. These cross-sectional findings indicate that elevated MMP-8 and LN-5 gamma2-chain fragment levels in PISF can reflect the active phase of the inflammatory peri-implant disease. Longitudinal studies are required to assess their use, either alone or in combination as molecular biochemical PISF markers, to predict the risk of progression of peri-implantitis, as well as to monitor the impact of treatment of the disease.
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PMID:Laminin-5 gamma2-chain and collagenase-2 (MMP-8) in human peri-implant sulcular fluid. 1265 74

Matrix metalloproteinase (MMP)-2 and membrane type 1-MMP can process the laminin-5 (Ln-5) gamma2-chain, revealing a cryptic site inducing epithelial cell migration. We investigated whether other MMPs process the Ln-5 gamma2-chain and related their ability to induce epithelial cell migration. The N-terminal sequences of the MMP-3, -12, -13, and -20 processed 80kDa Ln-5 gamma2x-chains were identical whereas the N-terminus of the 80kDa(MMP-8) Ln-5 gamma2x-chain was not. MMP-3, -13, -14, and -20 induced MCF-7 cell migration over Ln-5 while MMP-8 was a poor inducer of MCF-7 cell migration. In conclusion, several MMPs can process the Ln-5 gamma2-chain and induce epithelial cell migration.
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PMID:Matrix metalloproteinases process the laminin-5 gamma 2-chain and regulate epithelial cell migration. 1268 35

Primary culture of adipose tissue has often been used to investigate pharmacological and nutritional regulation of adipocyte gene expression. Possible alteration of adipocyte gene expression by primary culture on its own has not been explored in detail. In order to address this issue, explants were prepared from human subcutaneous adipose tissue recovered from plastic surgery and maintained for 0 to 48 h in DMEM supplemented with 10 % serum. At different time points, adipocytes were isolated from the explants by collagenase digestion, and mRNA expression and lipolysis were studied. Culture was associated with an accumulation of tumor necrosis factor-alpha (TNFalpha) in the culture medium, an increase in anaerobic glycolysis, and an increase in the basal lipolysis. In parallel, a rapid and dramatic decrease in the level of mRNA encoding for several adipocyte-specific proteins such as adipocyte lipid-binding protein, hormone-sensitive lipase, lipoprotein lipase, and peroxisome proliferation activating receptor-gamma2 was observed in isolated adipocytes. These downregulations were reminiscent of a dedifferentiation process. In parallel, primary culture was associated with an increase in adipocyte beta-actin, TNFalpha, glucose transporter-1 and hypoxia-induced factor-1alpha mRNAs. Treatment of explants with agents that increase cAMP (isobutylmethylxanthine and forskolin) prevented TNFalpha production and expression and culture-induced alterations of adipocyte gene expression. These data show that primary culture of human adipose tissue explants dramatically alters adipocyte gene expression.
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PMID:Culture of human adipose tissue explants leads to profound alteration of adipocyte gene expression. 1273 76

Although adherent junctions have been extensively studied, the role of tight junctions in cancer cell invasion is not sufficiently explored. We investigated whether claudin-1, a component of tight junctions, regulated invasion activity in oral squamous cell carcinoma (OSC) cells. The expression of claudin-1, activity of matrix metalloproteinase (MMP)-2, and cleavage of laminin-5 gamma2 chains were assessed by Western blot analysis, immunohistochemistry, and zymography in OSC cell lines (OSC-4 and NOS-2, highly invasive; OSC-7, weakly invasive) and their xenografts in severe combined immunodeficient (SCID) mice. The influence of claudin-1 small interfering RNA (siRNA) on the invasion activity of the cell lines was also investigated. Compared with OSC-7, both OSC-4 and NOS-2 more strongly expressed claudin-1 and possessed high activities of MMP-2 and MMP-9. Tumors formed in the tongues of SCID mice xenografted with OSC-4, NOS-2, and OSC-7 immunohistochemically revealed strong, moderate, and weak expression of laminin-5 gamma2 chains, respectively, and laminin-5 gamma2 chains were secreted in the conditioned medium of the cancer cells in parallel with the in vivo results. Claudin-1 siRNA largely suppressed the invasion of OSC-4 and decreased the activation of MMP-2, the expression of membrane-type MMP-1 (MT1-MMP), and the cleavage of laminin-5 gamma2. In addition, not only antibodies against MT1-MMP and epidermal growth factor receptor (EGFR) but also MMP-2 and EGFR inhibitors strongly suppressed the invasion activity of OSC-4. These results suggest that claudin-1 up-regulates cancer cell invasion activity through activation of MT1-MMP and MMP-2, which results in enhanced cleavage of laminin-5 gamma2 chains.
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PMID:Tight junction protein claudin-1 enhances the invasive activity of oral squamous cell carcinoma cells by promoting cleavage of laminin-5 gamma2 chain via matrix metalloproteinase (MMP)-2 and membrane-type MMP-1. 1670 50

Squamous cell carcinoma (SCC) of the tongue is the most common cancer in the oral cavity and has a high mortality rate. A total of 90 mobile tongue SCC samples were analysed for Bryne's malignancy scores, microvascular density, and thickness of the SCC sections. In addition, the staining pattern of cyclooxygenase-2, alphavbeta6 integrin, the laminin-5 gamma2-chain, and matrix metalloproteinases (MMPs) -2, -7, -8, -9, -20, and -28 were analysed. The expression of MMP-8 (collagenase-2) was positively associated with improved survival of the patients and the tendency was particularly prominent in females. No sufficient evidence for a correlation with the clinical outcome was found for any other immunohistological marker. To test the protective role of MMP-8 in tongue carcinogenesis, MMP-8 knockout mice were used. MMP-8 deficient female mice developed tongue SCCs at a significantly higher incidence than wild-type mice exposed to carcinogen 4-Nitroquinoline-N-oxide. Consistently, oestrogen-induced MMP-8 expression in cultured HSC-3 tongue carcinoma cells, and MMP-8 cleaved oestrogen receptor (ER) alpha and beta. According to these data, we propose that, contrary to the role of most proteases produced by human carcinomas, MMP-8 has a protective, probably oestrogen-related role in the growth of mobile tongue SCCs.
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PMID:Collagenase-2 (matrix metalloproteinase-8) plays a protective role in tongue cancer. 1825 13