Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this study was to determine how interferons alpha and gamma influence the expression of M(r) 72,000 type-IV collagenase (gelatinase A) and M(r) 92,000 type-VI collagenase (gelatinase B) genes and whether there are differences in their gene expression. Special emphasis was focused on the treatment time. Total cellular RNA from A2058 human melanoma cells treated for various time periods with IFN-alpha or gamma was analyzed by Northern- and slot-blot hybridization. Both M(r) 72,000 and M(r) 92,000 type-IV collagenase mRNAs were detectable in A2058 cells and mRNA levels for both gelatinases were significantly up-regulated in the cells treated for a short time period with either IFN-alpha or gamma. In contrast, a long-term treatment (7 days) with these drugs markedly down-regulated the genes for both gelatinase A and B. Zymographic analysis showed that human melanoma primarily secretes the gelatinase-A activity, which showed changes similar to those seen in the corresponding mRNA after the treatments with interferons. The expression of gelatinase-B activity was, however, detectable only transiently during the stimulating phase with IFN-alpha. Western immunoblot analysis showed that alterations in the levels of immunoreactive protein of gelatinase A in the cells correlated with the mRNA levels after the treatments. These findings suggest that IFN-alpha and IFN-gamma are potent regulators of both M(r) 72,000 and M(r) 92,000 type-IV collagenase/gelatinase A and B genes in human melanoma showing biphasic and parallel effects on mRNA levels of both enzymes, depending on the treatment time, and that the M(r) 72,000 metalloproteinase/gelatinase A is the predominant basement-membrane-degrading type-IV collagenase in human melanoma.
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PMID:Modulation of M(r) 72,000 and M(r) 92,000 type-IV collagenase (gelatinase A and B) gene expression by interferons alpha and gamma in human melanoma. 805 55

It is widely accepted that a major role of matrix metalloproteinases in the metastatic process is degradation of basement membrane during cancer cell invasion. We tested the hypothesis that the reduction in metastatic potential which has been demonstrated for B16F10 melanoma cells genetically engineered to overexpress tissue inhibitor of metalloproteinase-1 (TIMP-1) is caused by a decrease in their ability to extravasate. Using intravital videomicroscopy of chick embryo chorioallantoic membrane, we studied extravasation of B16F10 cells and B16F10 cells transfected to overexpress TIMP-1. More than 800 cells in 36 chick embryos were analyzed for each cell line during 72 h postinjection. TIMP-1 upregulation had no effect on the time course of extravasation, virtually all cells from both cell lines having extravasated by 36 h. We also studied the morphology of micrometastases at days 3 and 7. Lack of contact between cancer cells within micrometastases at day 3 and reduction in size and number of tumors at day 7 were observed for TIMP-1 overexpressor cells compared to B16F10. Our findings illustrate that the imbalance between TIMP and metalloproteinases created by overexpression of TIMP-1 in B16F10 cells reduces their metastatic ability in vivo by affecting tumor growth postextravasation.
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PMID:Overexpression of metalloproteinase inhibitor in B16F10 cells does not affect extravasation but reduces tumor growth. 806 80

Altered regulation of metalloproteinases may play a role in a variety of pathologic conditions including cancer. Previous studies have demonstrated transforming growth factor-beta 1 (TGF-beta 1)-mediated stimulation of expression and activation, and phorbol ester-mediated inhibition of matrix metalloproteinase (MMP)-2 (72-kDa type IV collagenase/gelatinase A), indicating a role for transmembrane signal transduction in MMP-2 regulation. We now describe a role for calcium mobilization in the regulation of MMP-2 expression. Receptor-operated calcium influx has been shown to be inhibited by a novel synthetic inhibitor, carboxy amido-triazole (CAI). Incubation of A2058 human melanoma, HT-1080 human fibrosarcoma, and OVCAR3 human ovarian cancer cells with CAI (0-10 microM) resulted in a dose-dependent reduction in MMP-2 latent and activated species activity by zymogram analysis of conditioned medium. This reduction is not due to direct inhibition of the enzyme by CAI or CAI-induced MMP-2 degradation. Decreased quantity of secreted MMP-2 protein in CAI-treated cells was shown by immunoblot and pulse-chase analysis of newly synthesized MMP-2. Cell coincubation with CAI (2 microM) and TGF-beta 1 (5 ng/ml) caused a decrease in the overall amount of latent and activated MMP-2 by zymogram and immunoblot analysis and showed that CAI inhibited TGF-beta 1 stimulation of MMP-2 production at the level of RNA expression. This was confirmed by Northern analysis of A2058 cells treated with CAI (2 microM) for 24 and 48 h and demonstrated a 55% reduction in message for MMP-2 and a 61% reduction in message for MMP-1, 54-kDa interstitial collagenase. Specificity for CAI action was demonstrated by equivalent MMP-2 inhibitory activity from analogs of CAI that retained the ability to inhibit calcium influx and by lack of inhibition by exposure to inactive CAI analogs that could not inhibit calcium influx. As an independent verification of specificity, a marked reduction in MMP-2 gelatinase activity by zymogram was shown after treatment of A2058 cells with SK&F 96365, an unrelated inhibitor of receptor-operated calcium influx. These results suggest a role for calcium-mediated signal transduction in the expression of metalloproteinases.
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PMID:Calcium influx modulates expression of matrix metalloproteinase-2 (72-kDa type IV collagenase, gelatinase A). 806 86

We recently reported an acidic actin co-expressed with beta and gamma actin in mouse B16 melanoma, whose expression was inversely correlated with the metastatic potential. The cDNA for this actin is slightly different from the hitherto recognized mouse beta actin cDNA, and we designated it beta m actin. In order to directly investigate the effects of beta m actin on metastasis, we transfected the beta m actin cDNA into a re-cloned B16-BL6 cell line which is more invasive than the highly metastatic cell line, B16-F10; we have already reported the suppressive effect of beta m actin on the invasiveness of B16-F10. Here we report on the decline in the metastatic ability of beta m-transfected cells. In the beta m-transfected B16-BL6 cell line, we observed an increase in the organization of actin stress fibers, accompanied by a decrease in metastasis to the lung, in the invasion of collagen gels, in in vivo invasiveness, and in cell migration on a glass plate covered with colloidal gold particles. We observed no correlation of beta m actin expression either with cell attachment to Matrigel, or with type-IV collagenase expression. These results suggest that beta m actin can play a role in reducing the invasiveness of mouse B16 melanoma, most probably through decreasing cell motility, which may thus result in suppression of the metastatic ability of cells.
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PMID:A variant actin (beta m) reduces metastasis of mouse B16 melanoma. 831 46

A panel of six monoclonal antibodies (MAbs) was raised against purified human fibroblast tissue inhibitor of metalloproteinase-1 (TIMP-1) and characterised. All possible antibody pairs were tested for their suitability as capture and revealing antibodies in a two-site enzyme-linked immunosorbent assay (ELISA) to measure total TIMP-1 (both free TIMP-1 and TIMP-1 together with matrix metalloproteinases (MMPs)). Using the best combination of MAbs the assay was optimised. The sensitivity of detection of the assay was 1.4 ng/ml, and inter- and intra-assay coefficients of variation were between 10.4-13.7% and 8.8-9.7%, respectively. Dilution series of human cerebrospinal and synovial fluids, plasma and sera paralleled those of the TIMP-1 standard curve indicating that the immunoreactivity detected in these samples was authentic TIMP-1. TIMP-2 shows no detectable cross reactivity in this assay confirming that this ELISA is specific for TIMP-1. The levels of total TIMP-1 and collagenase were measured in conditioned medium from A2058 human melanoma cells cultured in the absence or presence of human recombinant interleukin-1 alpha (hrIL-1 alpha). Total TIMP-1 was also measured in serum samples with known C-reactive protein (CRP) (n = 100) and alpha 1 antichymotrypsin (ACT) (n = 52) concentrations; no correlation was found between TIMP-1 levels and either of these acute phase reactants although the levels of TIMP-1 were raised when compared to normal sera. This ELISA provides a rapid and convenient procedure for the quantitation of total TIMP-1 in human biological fluids and supernatants from cultured cell lines.
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PMID:Development of an enzyme-linked immunosorbent assay to measure total TIMP-1 (free TIMP-1 and TIMP-1 in combination with matrix-metalloproteinases) and measurement of TIMP 1 and CRP in serum. 854 24

We used the Boyden chamber system to investigate the mechanism by which the antimetastatic agent sodium D-glucaro-delta-lactam (ND2001) inhibits tumor cell invasion, and by establishing what ND2001 did not achieve, we were able to pinpoint the areas in which it was successful as an inhibitor. ND2001 did not inhibit cell adhesion of a highly metastatic B16 melanoma variant (the B16 variant) to the reconstituted basal membrane Matrigel, nor did it affect the production or activity of basal membrane-degrading type i.v. collagenase, but, in the Boyden chamber, ND2001 inhibited cell migration of the B16 variant toward a chemoattractant, laminin, on the lower surface of a Matrigel-free filter set (haptotaxis). Lewis lung carcinoma (3LL) cells that had been treated with ND2001 also exhibited hardly any haptotaxis, although the cells showed no alteration in behavior during cell adhesion to Matrigel. Since ND2001 did succeed in inhibiting the pulmonary metastases of the B16 variant and 3LL, we infer that inhibition of the metastases by ND2001 in these tumors is likely to be due to the inhibition of haptotactic migration.
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PMID:Inhibition of tumor cell haptotaxis by sodium D-glucaro-delta-lactam (ND2001). 856

Four potent, synthetic inhibitors of matrix metalloproteinases (MMPs) were assessed as inhibitors of tumor growth and spontaneous metastasis to the lung. Mat Ly Lu rat prostate tumor, LOX human melanoma and M27 murine Lewis lung tumor were implanted subcutaneously (s.c.) in mice and allowed to grow for 3-12 days. The lungs of the tumor-bearing mice were then removed and implanted s.c. into untreated mice, and the outgrowth of secondary tumors from the implanted lungs measured. The incidence and rate of outgrowth of secondary tumors increased with the length of primary tumor growth, validating these measurements as indices of spontaneous metastasis to the lung. Compounds were tested by s.c. implantation of minipumps which delivered compound throughout the period of primary tumor growth and spontaneous metastasis to the lung at steady-state drug concentrations orders of magnitude greater than the concentrations needed to either inhibit collagenase, gelatinase or stromelysin in vitro. Inhibitor treatment slowed the growth of primary s.c. Mat Ly Lu and LOX tumors by 40-60% but had no significant effect on the growth of primary M27 tumors. Surprisingly, inhibitor treatment had no significant effect on the ability of the lung to generate secondary tumors when reimplanted s.c. in untreated mice. Because of the possible importance of cathepsins B, H and L in tumor growth and metastasis, the irreversible inhibitor E-64 was also infused by s.c. minipump. E-64 had no effect on the growth or spontaneous metastasis of Mat Ly Lu or M27 tumors.
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PMID:Effect of matrix metalloproteinase inhibitors on tumor growth and spontaneous metastasis. 860 25

Ultraviolet light (UV) and different DNA-damaging agents are known to induce AP-l-transcription-factor activity. Whereas UV induction appears to be triggered by events at the cell membrane, the mechanism of AP-l activation by alkylating or platinating agents is not known. We have here examined the effect of cisplatin on AP-l activity in RPMI-8322 melanoma cells. Cisplatin was found to induce binding of nuclear proteins to TRE elements from the c-jun and collagenase-gene promoters, and was also found to induce activation of a c-jun-promoter reporter construct. Compared with stimulation by UV, cisplatin stimulation of c-jun-promoter activity was found to be less sensitive to a dominant negative mutant of Raf-I protein kinase. Furthermore, whereas UV treatment resulted in strong MAP-kinase activation, cisplatin treatment resulted only in a weak and transient increase. These data suggest that the Raf-MAPK pathway is of minor importance for the induction of c-jun-promoter activity by cisplatin. Finally, we report that cisplatin induction of c-jun in RPMI-8322 cells was blocked by herbimycin A, an inhibitor of Src-family tyrosine kinases. In contrast, UV induction of c-jun was not blocked by herbimycin A. In conclusion, our data strongly suggest that UV and cisplatin induction of c-jun mRNA in RPMI-8322 melanoma cells occur by distinct mechanisms.
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PMID:Different mechanisms are responsible for c-jun mRNA induction by cisplatin and ultraviolet light. 863 98

The thiol N-acetylcysteine (NAC) is a promising cancer chemopreventive agent which acts through a variety of mechanisms, including its nucleophilic and antioxidant properties. We have recently shown that NAC inhibits type-IV collagenase activity as well as invasion, tumor take and metastasis of malignant cells in mice. NAC is also known to attenuate the cardiotoxicity of the cytostatic drug doxorubicin (DOX, Adriamycin). The present study was designed to evaluate whether the combination of NAC and DOX treatments in mice injected with cancer cells could affect their tumorigenic and metastatic properties. Six separate experiments were carried out, using a total of 291 adult female mice. In experimental metastasis assays, in which B16-F10 melanoma cells were injected i.v. into (CD-1)BR nude mice, DOX significantly reduced the number of lung metastases when administered i.v. at a dose of 10 mg/kg body weight, 3 days after the i.v. injection of cancer cells. NAC inhibited lung metastases when added to the medium of cancer cells before their i.v. injection. The combined treatment with DOX and NAC, under various experimental conditions, was highly effective, showing a synergistic reduction in the number of mestastases. In tumorigenicity and spontaneous metastasis assays, in which B16-BL6 melanoma cells were injected s.c. into the footpad of C57BL/6 mice, DOX decreased the number of lung metastases when given i.p. at 2 mg/kg body weight. Oral NAC exerted significant protective effects, and considerably prolonged survival of mice. The combined treatment with DOX and NAC again showed synergistic effects on the frequency and weight of primary tumors and local recurrences, and completely prevented the formation of lung metastases in the experiment in which these end-points were evaluated at fixed times. While injection of DOX 7 days after implantation of cancer cells failed to improve the cancer-protective effects of NAC, its injection after I day resulted in a striking inhibition of lung metastases. These findings demonstrate an evident synergism between DOX (given parenterally) and NAC (given with drinking water) in preventing tumorigenicity and metastases. The indications of these animal studies warrant further evaluation in clinical trials.
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PMID:Synergism between N-acetylcysteine and doxorubicin in the prevention of tumorigenicity and metastasis in murine models. 882 57

Metastasis is a complex process, almost a cascade, involving multiple steps and activities. However, an important factor is that malignant cells are able to penetrate through the multiple basement membrane barriers surrounding tissues, blood vessels, nerves and muscle that would otherwise block their dissemination. Penetration of malignant tumor cells through basement membrane is an active process requiring proteolysis. We report here that inhibitors of both the cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism convert mouse melanoma and human fibrosarcoma cells to a non invasive state by reducing the production of MMP-2, an enzyme required for the degradation of basement membranes. Specific metabolites of each pathway, i.e. PGF2 alpha and 5-HPETE, are able to transcend the block and restore collagenase production, invasiveness in vitro and metastatic activity in vivo. These studies indicate a key role for arachidonic acid metabolites in metastasis and suggest novel therapeutic approaches for inhibiting the spread of cancer.
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PMID:Identification of arachidonic acid pathways required for the invasive and metastatic activity of malignant tumor cells. 890 Apr 40


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