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

Normal and premalignant mouse mammary epithelial cells can be prepared in high yields by collagenase dissociation of minced glands followed by a brief, differential centrifugation to remove contaminating fibroblasts and fat cells. The major difficulties in preparing pure cultures in quantity are 1) incomplete dissociation of gland material, and 2) cell death during enzymatic digestion. These problems are eliminated by careful selection of collagenases for dissociation. Normal and premalignant mammary epithelial cells are morphologically indistinguishable from malignant mouse mammary epithelial cells in primary monolayer cultures. In addition, the growth rates and saturation densities achieved by normal mammary epithelial cells are indistinguishable from those of malignant mammary epithelial cells in primary culture. In both cases, a monolayer of cells is preserved with no evidence of focal overgrowth. Malignant adenocarcinoma mammary cells can however be distinguished from normal mammary epithelial cells by virtue of differences in their surface interactions with concanavalin A. A hemadsorption assay using Con-A-coated erythrocytes was the most sensitive indicator for these differences. In hemadsorption assays malignant mammary epithelial cells were half-maximally reactive with 2.5 mug/ml concanavalin A, while normal cells were completely unreactive even at concanavalin A concentrations five-times higher. Premalignant mammary epithelial cells were as reactive as malignant mammary epithelial cells in the hemadsorption assays. Hemadsorption of malignant cells was observed in primary and secondary cultures of epithelium as well as in cell lines. Malignant cells forming mammary adenocarcinomas were as highly reactive as malignant cells forming scirrhous carcinomas. Malignant cells not releasing mammary tumor virus (MuMTV) were as reactive as cells releasing that virus. Adsorption of concanavalin-A-coated erythrocytes to normal mammary epithelial cells could be induced by brief treatment of cell monolayers with hyaluronidase. Exposure of active sites was not affected with either trypsin or collagenase. Our results show that while the growth of malignant cells does not serve to distinguish them from normal cells in monolayer culture, surface changes do exist which can be identified by differences in concanavalin A reactivity. Since the earliest transformants identifiable in vivo (premalignant) have undergone conversion of the surface marker, concanavalin-A-mediated hemadsorption provides a sensitive measure for mammary epithelial cell transformants in vitro.
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PMID:Markers to distinguish normal and neoplastic mammary epithelial cells in vitro: comparison of saturation density, morphology and concanavalin A reactivity. 18 59

Two murine colon adenocarcinoma cell lines were established from primary cultures. The MCA-38 cell line was begun by treatment of the primary culture with trypsin to remove the fibroblastoid elements. The MCA-36 epithelial cells were sensitive to trypsin; therefore, the growth medium of MCA-36 primary cultures was augmented with collagenase to release the tumor-cell elements from the fibroblast network. These tumor elements were dissociated with trypsin and placed in tissue culture. Each cell line was cultured for at least 10 passages in vitro and gave rise to tumors when reimplanted in vivo.
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PMID:Murine colon adenocarcinomas: methods for selective culture in vitro. 125 4

We describe an in vitro assay for measuring the ability of tumour cells to permeabilize basement membranes, using transwell chambers coated with the reconstituted basement membrane, matrigel. Unlike previous matrigel-based procedures which quantified passage of tumour cells across a matrigel barrier, the new assay measures the ability of tumour cells to degrade the basement membrane and increase the diffusion rate of fluorescent (FL) dextran through the barrier. The procedure has the major advantage that permeability can be rapidly and accurately quantified, either by fluorometry or by the use of radiolabelled dextran, thus avoiding tedious and subjective scoring methods. Optimal conditions for the assay are described. In addition, it is demonstrated that the assay can clearly discriminate between metastatic and non-metastatic tumour cell lines, metastatic tumours permeabilizing the basement membrane and non-metastatic counterparts failing to do so. A range of enzyme inhibitors suggested that the increase in basement-membrane permeability caused by the metastatic mammary adenocarcinoma 13762 MAT is probably dependent upon the synergistic action of several degradative enzymes, namely proteases, type-IV collagenase, and heparanase. Furthermore, the ability to permeabilize the basement membrane was dependent upon intact tumour cells; tumour cell extracts, lysates and supernatants were inactive.
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PMID:A basement-membrane permeability assay which correlates with the metastatic potential of tumour cells. 139 13

Although many agents that interfere with clotting mechanisms have been investigated for their potential to inhibit metastasis, their toxicity has prevented administration of sufficiently high doses to achieve inhibition of metastasis in clinical trials. Nafamostat mesilate (FUT-175), a synthetic serine protease inhibitor, inhibited liver metastasis in a CDF1 mice model with colon 26 adenocarcinoma cells. The apparently dose-dependent inhibitory effect was seen 21 days after all of the doses tested (0.3, 1.0, 3.0 and 10.0 mg/kg for 7 days) but the effect was only statistically significant (P less than 0.01) at the highest dose. The blood concentrations 3 min after dosing were less than 10(-6) M for all of the doses tested. At a concentration of 10(-5) M or less nafamostat mesilate was not cytotoxic towards colon 26 cells in vitro. The results indicate that it may not be difficult to achieve blood nafamostat mesilate concentrations that inhibit metastasis in mouse liver. Possible mechanisms of nafamostat mesilate are inhibition of extravasation and invasion of cancer cells, inactivation of collagenase due to inhibition of plasmin activity and inhibition of the formation of the cancer cell thrombus, and arrest in the capillaries through inhibition of thrombin activity. These preliminary results suggest that peri-operative administration of nafamostat mesilate may prevent metastasis into the liver after surgery for gastrointestinal malignancies.
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PMID:Inhibitory effect of nafamostat mesilate on metastasis into the livers of mice and on invasion of the extracellular matrix by cancer cells. 151 73

Basement membranes (BM) are elements of the extracellular matrix that are essential for growth and differentiation of tissues. Several collagenolytic enzymes of tumor cells are involved in degradation of the extracellular matrix; growth and inhibitor factors [e.g. Epidermal Growth Factor (EGF), Transforming Growth Factors alpha and beta (TGF-alpha, beta)] seem to be involved in the extracellular matrix formation and degradation. To establish a possible association between the presence of collagenase (C), urokinase-type plasminogen activator (uPA) and the neoplastic growth of the endometrium, 44 endometrial specimens (14 proliferative, 11 secretive, 7 adenomatous hyperplasia, 12 adenocarcinoma) were studied using immunohistochemistry with antisera for C, uPA, EGF receptors and TGF-alpha. Immunostaining for collagenase revealed a positive reaction in moderately differentiated adeno-carcinoma without staining the normal and hyperplastic endometrium. A progressive increase in uPA immunostaining was observed in proliferative and neoplastic endometrium. TGF-alpha and its receptor (EGFr) were stained in proliferative and more clearly in hyperplastic and carcinomatous endometrium. In conclusion, BM play an important role in proliferation and differentiation of human endometrium; their degradation influences estrogen transportation from blood to the stroma. Endometrial BM degradation is associated with the presence of collagenolytic enzymes and growth factors.
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PMID:Basement membrane in human endometrium: possible role of proteolytic enzymes in developing hyperplasia and carcinoma. 164 21

We developed a method for measuring the activity of type III collagenolytic enzyme in lung cancer tissue, using as substrate, type III collagen purified from human placenta. In this method [3H]propionate is used for labeling type III collagen, with bacterial collagenase used for making the standard curve. It, therefore, becomes possible to compare type III collagenolytic activity with those of other collagen subtypes (types I and IV). As this method is a fibril assay it is not susceptible to trypsin or other proteases. The average type III collagenolytic enzyme activity was higher in squamous cell carcinoma than in adenocarcinoma, while that of lung cancer tissue exceeded that of normal lung tissue. The activity of type III collagenase increased with the progression from one disease stage to the next.
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PMID:Assay for type III collagenolytic activity in lung cancer tissue. 166 47

Various approaches to isolation of tumor cells are analyzed on the basis of examination of 46 human pulmonary tumors of different histologic types. Mechanical treatment alone resulted in the death of the majority of tumor cells. Short trypsin treatment (for 10-15 min in several stages) proved to be the most suitable for disaggregation of small-cell carcinoma, adenocarcinoma, and carcinoid samples. A specific approach has been developed for isolation of cells from squamous-cell carcinoma, consisting in tumor treatment with 0.25 percent trypsin at 4 degrees C for 16-18 h, followed by DNAase, collagenase, and trypsin treatment, and then again trypsin treatment at 37 degrees C for 10-15 min. The suggested approaches permit a harvest of at least 6 x 10(6) tumor cells from 1 g of tissue, with more than 70 percent of these cells viable.
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PMID:[Preparation of tumor cells from human lung cancer tissue for the purpose of cloning]. 170 81

Twenty-five surgical specimens of malignant human prostate, 3 lymph nodes with metastatic prostate carcinoma, 11 normal human prostates, as well as 3 human prostate cell lines (DU-145, PC3 and LNCaP) were examined for the expression of the human matrix metalloproteinase-7 gene (MMP-7) from the human collagenase family (originally called PUMP-1 for putative metalloproteinase-1) [Quantin et al. (1989) Biochemistry 28:5327-5334; Muller et al. (1988) Biochem J 253:187-192; Matrisian and Bowden (1990) Semin Cancer Biol 1:107-115]. Northern blots were prepared using total RNA extracted from 18 prostate adenocarcinomas, 2 lymph nodes with metastatic prostate carcinoma and 11 normal human prostates. When the northern blots were hybridized with a 32P-labeled MMP-7 cDNA probe, a 1.2-kb mRNA was detected in 14 out of 18 prostate adenocarcinomas, 1 out of 2 metastatic lymph nodes, and 3 out of 11 normal prostates. The 3 human prostate cell lines did not show any evidence of the MMP-7 transcript. In situ hybridization was conducted to localize the MMP-7 mRNA to individual cells using a 35S-labeled MMP-7 cRNA. In situ hybridization was carried out on snap-frozen tissue sections of 7 prostate adenocarcinomas and 3 lymph nodes containing metastatic prostate adenocarcinoma using the same tissues previously probed by northern analysis as well as new samples. In situ hybridization revealed that the MMP-7 gene was expressed in the epithelial cells of primary prostate adenocarcinoma as well as in invasive and metastatic cells. MMP-7 expression was also seen focally in some dysplastic glands but not in stroma. Additional northern blot analysis was performed using probes to human type-IV collagenase, type-I collagenase and stromelysin I in human prostate adenocarcinoma as well as normal prostate tissue. Our results indicated that 6 out of 10 adenocarcinoma samples and none of the 4 normal samples were positive for type-IV collagenase transcripts. Tissue samples were also examined for the expression of type-I collagenase (9 adenocarcinomas and 4 normal) and stromelysin I (13 adenocarcinomas) by northern analysis. None of the tissues was found to express the transcripts of interest at detectable levels. These data suggest that certain metalloproteinases are present in prostatic adenocarcinoma and may play a role in invasion and metastasis.
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PMID:Expression of metalloproteinase genes in human prostate cancer. 184 60

We have examined the expression of murine tissue inhibitor of metalloproteinases (TIMP) in nonmetastatic and metastatic cell lines derived from SP1 murine mammary adenocarcinoma cells. We observed decreased levels of TIMP mRNA and activity in metastatic cells as compared to their nonmetastatic equivalents in the absence of fetal bovine serum. Lower levels of TIMP mRNA correlated to decreased levels of transcription of the TIMP gene. Net collagenase activity was higher in metastatic cells, but metastatic and nonmetastatic cells secreted similar levels of total collagenase (mainly type IV). This suggests that decreased TIMP gene expression results in increased net collagenase activity in malignant cells.
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PMID:Decreased expression of tissue inhibitor of metalloproteinases in metastatic tumor cells leading to increased levels of collagenase activity. 184 44

Ten cases of malignant mesothelioma (MM), as diagnosed by clinical history and light and electron microscopy, were studied with polyclonal antibodies directed against the basement membrane-specific proteins, type IV collagen and laminin, as well as with monoclonal antibodies which recognize two epitopes of the laminin receptor (LR). All formalin-fixed, paraffin-embedded mesothelioma tissues examined demonstrated intracytoplasmic immunoreactivity for the basement membrane proteins. Extracellular staining was minimal, analogous to the staining reactions observed in adenocarcinomas of the breast and lung, which on light microscopy mimicked the morphologic appearance of MM. Similarly, LRs were identified on MM cells by intense positive staining. Immunoreactivity was also evident on nonneoplastic mesothelioma and adenocarcinoma cells but with greater heterogeneity and less intensity. It may be concluded from these results that (a) malignant mesotheliomas have the ability to synthesize components of the basement membrane; (b) enhanced attachment to extracellular matrix by MM would be anticipated as laminin receptors are present in large numbers on the surface of mesothelioma cells; (c) the reason for lack of intensiveness by MM cells remains speculative; type IV-specific collagenase may play a role in regulating this function in these tumor cells.
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PMID:Immunoreactivity in malignant mesotheliomas with antibodies to basement membrane components and their receptors. 213 26


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