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)

The level of unscheduled DNA synthesis in the parenchymal cells from hyperplastic nodules and from the entire liver of rats fed N-2-fluorenylacetamide was studied and compared with that of normal liver cells. Measurements of unscheduled DNA synthesis were carried out by the use of a primary liver cell culture system. Livers were perfused with collagenase, the cells from individual hyperplastic nodules, and/or from the whole liver aspirated and plated onto plastic Petri dishes. Simultaneous histochemical measurements of beta-glucuronidase were carried out in the cultured cells as an aid in distinguishing functional cell types. The cells from hyperplastic nodules obtained from the liver during carcinogen feeding survived much longer than normal liver cells in culture. The level of unscheduled DNA synthesis was determined radioautographically after exposing cells to ultraviolet light and incubating with [3H]thymidine. [3H]Thymidine labeling was variable among individual nodules or animals and fluctuated as a function of the number of days in culture. In general, however, the level of unscheduled DNA synthesis in the cells from hyperplastic nodules was always higher than or similar to that of normal liver cells. Thus, the cells of hyperplastic nodules are not more readily transformed into the malignant state than normal cells as a result of their lowered DNA repair mechanisms.
Cancer Res 1975 Dec
PMID:Unscheduled DNA synthesis in cells from N-2-fluorenylacetamide-induced hyperplastic nodules of rat liver maintained in a primary culture system. 123 66

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.
J Natl Cancer Inst 1976 Apr
PMID:Murine colon adenocarcinomas: methods for selective culture in vitro. 125 4

NIH-3T3 cells are non-tumorigenic when injected into athymic mice. If these cells are mixed with an extract of basement-membrane proteins (matrigel) and injected s.c., they form locally invasive and highly vascularized tumors. Cells cultured from the NIH-3T3-matrigel-induced tumors showed a transformed phenotype and lacked contact inhibition. When cultured in a gel of matrigel, they proliferated and formed branched and invasive colonies. In contrast, the parental NIH-3T3 cells cultured on matrigel remained as cell aggregates and were not invasive. I.V. injections of the tumor-derived NIH-3T3 cells produced many colonies on the surface of the lungs, whereas the parental NIH-3T3 cells were not metastatic. Zymographic analysis of the conditioned media obtained from both the tumor-derived and parental NIH-3T3 cells demonstrated higher amounts of the 72-kDa gelatinase (type-IV collagenase) enzyme in the tumor-derived cells. Also, tumor-derived NIH-3T3 cells, but not parental NIH-3T3 cells, secreted the 92-kDa type-IV collagenase. These studies suggest that the interaction of pre-malignant NIH-3T3 cells with extracellular matrix components may contribute to the process of tumor progression.
Int J Cancer 1992 Jul 09
PMID:Malignant transformation of NIH-3T3 cells after subcutaneous co-injection with a reconstituted basement membrane (matrigel). 131 8

We have studied the in vitro invasive properties of 3 cell lines derived from the co-transfection of rat embryo fibroblasts (REF) with EIA genes deficient in exon 2 and T24-ras. All 3 cell lines showed invasive properties at passage 10 after isolation. Invasive cells expressed elevated levels of stromelysin-1 and reduced levels of 68-kDa type-IV collagenase compared with untransfected REF. In 2 cell lines the invasive capacity increased during in vitro propagation. The expression of stromelysin-1 increased during this process, whereas 68-kDa type-IV collagenase was persistently expressed at reduced levels. In the third clone analyzed, the invasive capacity decreased during culture, in parallel with decreased expression of stromelysin-1. The low level of stromelysin-1 expression observed in this cell line did not result from loss of AP-1-transcription-factor activity, and was not reversed by phorbol-ester treatment.
Int J Cancer 1992 Jul 09
PMID:Elevated stromelysin-1 and reduced collagenase-IV expression in invasive rat embryo fibroblasts expressing E1A deletion mutants + T24-H-ras. 131 10

Mucinous colorectal cancer often presents at an advanced stage. We have previously observed that mucin production by human colon-cancer cells correlates with their ability to colonize the liver in experimental animal models. The present study was undertaken in order to further elucidate the mechanisms by which production of mucin by colon-cancer cells affects metastasis. Cell lines showing high mucin production (HMP) (HM 7, HM 3 and LS LiM 6) demonstrated increased adherence to basement membrane proteins and invaded a reconstituted basement membrane to a greater extent than their counter-part cell lines showing low mucin production (LMP) (LS174T and LM 12). Adherence of the LMP parental cell line LS174T to various matrix proteins was potentiated by the addition of purified human colon-cancer mucin in a dose-dependent fashion. HMP cell lines secreted more proteolytically active type-IV collagenase than LMP lines, and collagenase activity was further stimulated by purified mucin in a dose-dependent manner. Specific inhibition of mucin O-glycosylation by benzyl-alpha-N-acetylgalactosamine significantly affected each of the metastasis-related events, with the greatest effect on the HMP cell lines. The present data further indicate that mucin may play an important role in the metastatic process.
Int J Cancer 1992 Aug 19
PMID:The role of mucin in colon-cancer metastasis. 132 40

We have screened six human squamous carcinoma cell lines for their ability to invade connective tissue by using the experimentally modified chorioallantoic membrane of a chick embryo as an in vivo model of invasion. In confirmation of our earlier studies, all the invasive cell lines expressed high levels of surface-bound urokinase type plasminogen activator (uPA). However, some cell lines expressing this activity were not invasive, suggesting that surface uPA, although necessary, was not sufficient. Since in addition to fibronectin, that can be degraded by uPA or plasmin, chorioallantoic membrane connective tissue contains collagen, we examined the profile of collagenases secreted by the various cell lines in search for an activity that would coincide with the invasive phenotype. We found, using gelatin substrate gels, that type IV gelatinase was produced by all six cell types tested, three cell types produced the M(r) 92,000 gelatinase, and three a lower-molecular-weight activity, which we identified by immunoprecipitation with specific antibodies, and by a direct assay of activity, as interstitial collagenase. Only the latter cells were found to be highly invasive. We showed previously that continuous culture in vitro of one of the carcinoma cell lines, HEp3, led to a gradual extinction of their malignant phenotype. To confirm the correlation between invasion and the production of interstitial collagenase, we examined these two functions in cells freshly isolated from a HEp3 tumor and intermittently during passage in vitro. We found that, although the surface uPA activity was slightly diminished in the in vitro grown cultures, it was still within the range of values found in highly malignant cells, suggesting that it is not the reason for the decrease in invasiveness. In contrast, the reduction in interstitial collagenase closely followed the loss of the invasive phenotype; after 30 in vitro passages the cells were almost completely devoid of interstitial collagenase and unable to invade. The decrease in collagenase activity was not the result of an increased tissue inhibitor of metalloproteinases production.
Cancer Res 1992 Dec 15
PMID:Invasion of connective tissue by human carcinoma cell lines: requirement for urokinase, urokinase receptor, and interstitial collagenase. 133 82

We have examined the antimetastatic effects of taxol on a PC-3 human prostatic tumor variant (PC-3 ML) which metastasizes to the lumbar vertebrae in severe combined immunodeficiency-carrying (SCID) mice. Immunofluorescence labeling indicated that taxol (0.5 to 1.0 microM for 6 h) produced an abnormal bundling of microtubules in a dosage-dependent manner. Slot blotting and gelatinase assays revealed that taxol inhibited secretion of the M(r) 72,000 and M(r) 92,000 type IV collagenases plus a M(r) 57,000 gelatinase. Radioimmunoprecipitation measurements confirmed that the drug inhibited both the secretion and the synthesis of the M(r) 72,000 collagenase. Taxol also blocked total protein secretion but did not influence total protein synthesis or turnover. Boyden chamber chemotactic studies further showed that taxol (0.5 to 1.0 microM) inhibited invasion of Matrigel. More importantly, studies in SCID mice demonstrated that taxol (50 to 250 mg/m2/day) blocked the establishment, growth, and long-term survival of PC-3 ML cells.
Cancer Res 1992 Jul 01
PMID:Taxol blocks processes essential for prostate tumor cell (PC-3 ML) invasion and metastases. 135 84

In order to shed light on the causal mechanisms of hepatocarcinogenesis in the transgenic mouse into which the albumin-promotor-regulated SV40-T antigen gene has been introduced (T+ mouse), and especially on the frequent chromosomal aberrations seen in cultured hepatocytes and hepatocellular neoplasms derived from such animals, the frequency of sister chromatid exchange (SCE) and karyotype abnormalities were investigated in a hepatocyte primary culture system. Cells were obtained through collagenase perfusion from T+ mice at 16-18 days of age, when no morphological changes are apparent, and from nontransgenic littermates, and cultured in the presence of bromodeoxyuridine. SCE was seen in transgenic hepatocytes twice as frequently as in their normal counterparts. No karyotype abnormalities in terms of numerical change or gross aberration were detected at this phase. The results thus suggest mutagenic properties for the T antigen, which may play an important role in hepatocarcinogenesis in this transgenic mouse.
J Cancer Res Clin Oncol 1992
PMID:Frequent spontaneous sister chromatid exchange in hepatocytes of transgenic mice harboring the SV40-T antigen gene. 138 48

Matrix metallo-proteinases (MMPs) are a group of enzymes thought to be responsible for both normal connective tissue matrix remodelling and accelerated breakdown associated with tumor development. The distribution of 3 major matrix metallo-proteinases was studied in human mammary pathology: collagenase (MMP1) which degrades fibrillar interstitial collagens, a 72-kDa gelatinase (MMP2) which mainly degrades type IV collagen and denatured collagens, and stromelysin (MMP3) which has a wider range of action, degrading several matrix components including the core proteins of proteoglycans, laminin and non-helical regions of collagens. These MMPs and the MMP tissual inhibitor (TIMP1) were detected by immunohistochemistry in 30 benign and 79 malignant lesions of the breast. MMPs were detected in 1 fibroadenoma (collagenase) and 22 breast carcinomas: collagenase (9 cases), stromelysin (12 cases) and gelatinase (16 cases) with a limited distribution. Tumor cells were preferentially labelled and the localization of gelatinase and stromelysin at the periphery of some non-invasive and well-differentiated clusters supports the role of these enzymes in the breakdown of basement membranes. Only a few stromal cells (fibroblasts) were found to be immunopositive. In contrast, TIMP1 was more frequently detected, and was found in 7 benign lesions and 55 carcinomas out of 79. It was mainly localized at the periphery of the endothelial cells but was occasionally detected in cancer cells and fibroblasts.
Bull Cancer 1992
PMID:Immunolocalization of matrix metallo-proteinases and their tissue inhibitor in human mammary pathology. 139 65

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.
Int J Cancer 1992 Sep 30
PMID:A basement-membrane permeability assay which correlates with the metastatic potential of tumour cells. 139 13


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