Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Herpes simplex virus type 2-transformed hamster embryo fibroblasts (333-8-9 cells) produce increased plasminogen activator (PA) compared with normal hamster cells. These cells produce undifferentiated fibrosarcomas at the inoculation site in newborn hamsters, and metastasize to the lungs. Using a direct PA assay, in which 125I-labeled plasminogen is cleaved, the optimum pH and osmolarity for detection of the 333-8-9 extracellular PA were pH 8.9 and approximately 150 mOsmol. Secretion of enzyme did not vary significantly on a per cell basis over cell densities from 0.1 to 8.0 X 10(7) cells/T-75 cm2 flask. This assay demonstrates that the 333-8-9 cells produce at least 20-fold greater levels of PA than normal cell counterparts. Based on the molecular weight (50-58 kDa) of secreted 333-8-9 cells PA and lack of fibrin stimulation, we conclude that it is a urokinase type PA. Subclonal lines of the 333-8-9 cells, selected for an increased PA phenotype were stable in culture, more tumorigenic and probably more metastatic. Correlation of these two events was examined by passaging 333-8-9 cells in vivo to select for greater tumorigenic potential and then determining the production of PA by the in vivo-derived sublines. The metastatic potential of the resulting cells was heterogeneous. Increased PA production upon increased passage in vivo did not always occur, whether the cells were passaged as subcutaneous tumors or as ascites tumors. Thus, while enzyme production correlated with tumorigenicity when selecting cells for an increased protease phenotype, this correlation was not observed when selecting for in vivo tumorigenicity. The results suggest that increased ability to make PA represents only one of multiple selective advantages for tumor growth.
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PMID:Phenotypic properties of herpesvirus-transformed cells with high tumorigenic and metastatic ability. 215 88

Using B16 F10 murine melanoma cells and sublines generated from the JB/MS melanoma which exhibit various degrees of melanogenesis, the relationships among differentiation, tumorigenicity, and metastatic potential were examined. The effect of melanocyte-stimulating hormone (MSH), which specifically stimulates differentiation of melanocytes, was also studied. All melanoma lines tested were capable of growing as experimental pulmonary metastases but, surprisingly, the undifferentiated and amelanotic JB/MS-w cells failed to grow as primary subcutaneous tumors. JB/MS-w cells, which had few surface MSH receptors, did not respond to MSH with an increase in melanin production, unlike the other cell lines. Although in vitro treatment with MSH did not change the rates of growth of primary tumors by these cell lines, such treatment decreased the number of pulmonary metastases from B16 F10, JB/MS cells, JB/MS-b1 cells and JB/MS-w cells. Conversely, MSH treatment significantly increased the rates of pulmonary metastases from JB/MS-p cells. The expression of surface melanoma antigens, urokinase-type plasminogen activity and susceptibility to natural killer cells were examined. MSH did not significantly alter surface melanoma antigen expression, but increased the natural killer cell susceptibility of B16 F10, JB/MS and JB/MS-b1 cells, cells which possess abundant surface MSH receptors. There was an inverse correlation between differentiation (pigmentation) and proliferation in vitro, and the more pigmented melanoma cells (B16 F10, JB/MS and JB/MS-b1) expressed relatively lower levels of class-I MHC, relatively higher levels of class-II MHC and the highest metastatic capacity. These results demonstrate that MSH possesses the capacity to regulate not only melanogenesis, but also other factors critical to the metastatic growth of the cells.
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PMID:Differentiation and the tumorigenic and metastatic phenotype of murine melanoma cells. 216 2

This prospectively randomized clinical trial was carried out in four Dutch hospitals to reduce the development of metachronous liver metastases and to get a better survival in patients with colorectal malignancies after surgically radical en bloc resection of the primary tumor and the regional lymph nodes. Three hundred seventeen patients were randomized to participate in three trial arms. One group of patients was treated by surgery alone (control group); in the other patients a catheter was placed in the dilated umbilical vein and advanced until the tip was lying in the left branch of the portal vein. Fifty percent of these patients got immediate postoperative portal infusion with 1 g 5-fluorouracil (5-FU) and 5000 U heparin daily for 7 days; the others received portal vein infusion with urokinase 10.000 U/hour for 24 hours only. Three hundred four patients were eligible. Overall hospital mortality was 3.6% (11 patients) and was not influenced by adjuvant treatment. After a median follow-up of 44 months 66 patients have died with relapse and 21 as a result of other causes. The chance of developing liver metastases and other distant metastases after portal infusion with 5-FU/heparin was one third of the chance in the control group (P less than 0.001). Only an insignificant reduction of the average death rate in the 5-FU/heparin group was found. In the urokinase group no significant effect in reducing metastases or in survival was noted. Before recommending cytotoxic portal infusion as an adjuvant treatment in patients with colorectal cancer, detailed analysis of other ongoing portal infusion studies has to be awaited and careful calculations have to be made regarding how many patients really can be saved by this treatment.
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PMID:Adjuvant portal liver infusion in colorectal cancer with 5-fluorouracil/heparin versus urokinase versus control. Results of a prospective randomized clinical trial (colorectal adenocarcinoma trial I). 240 56

Components of the plasmin system were comparatively studied in lymph node metastases and corresponding primary tumors by immunofluorescence. Primary tumors, all adenocarcinomas, originated from large bowel (N = 12) or breast (N = 10). We used antisera against plasminogen (Pg), plasminogen activators (PA) such as urokinase (UK) and tissue type PA (t-PA), plasmin inhibitors such as alpha 2 anti-plasmin (alpha 2AP) and alpha 2 macroglobulin (alpha 2M), plasmin-alpha 2 anti-plasmin complex (PAPC). Positivity with anti-PAPC serum was considered as proving that plasmin was formed by Pg activation. The following results were obtained. Breast adenocarcinomas were more strongly stained than colorectal adenocarcinomas using antisera against Pg, PAPC and PA, while their reactivity was much weaker with antisera against both plasmin inhibitors. Lymph node metastases from colorectal adenocarcinomas were more strongly stained than primary tumors using antisera against PAPC and PA. Reactivity with anti-Pg was similar, while that with antisera against plasmin inhibitors was much weaker. Metastasis from breast adenocarcinomas, on the average, showed the same type of staining as primary tumors. However, there was a slight decrease in reactivity with anti-Pg and PAPC in metastases. Tumor cells invading lymphoid areas in metastatic lymph nodes were often strongly labeled using antisera against Pg and UK. Staining was less strong or less frequent using antisera against PAPC and t-PA. These results favor the role of plasmin in the degradation of basement membrane and connective tissue components, thus implicating it in the invasiveness of tumor cells, at least in most primary tumors and metastases.
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PMID:The plasmin system in human adenocarcinomas and their metastases. A comparative immunofluorescence study. 243 33

To assess the postulated correlation between plasminogen activators (PAs) and malignancy, we determined the mRNA content for urokinase-type (u-PA) and tissue-type (t-PA) enzymes in a prospective series of 29 primary lung and 27 primary breast carcinomas. Dot blots of total RNAs were hybridized with appropriate cRNA probes under conditions that allow quantitative measurement of the mRNA level for each PA. Most tumors (43 of 56) had a u-PA mRNA content higher than the mean + 1 SD of nonmalignant tissue counterparts. A large, 4- to 20-fold, increase in u-PA mRNA content was demonstrated in 14 of 29 lung carcinomas and in 10 of 27 breast carcinomas. A statistically significant correlation (Fisher's test, P = 0.007) was found between elevated u-PA mRNA content in lung carcinomas and the presence of regional lymph node metastases. These results are consistent with a role for u-PA in tumor invasiveness and metastatic propensity and may have important prognostic and therapeutic implications.
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PMID:Increase of urokinase-type plasminogen activator gene expression in human lung and breast carcinomas. 244 May 56

The levels of several tumor associated proteases, including plasminogen activators (PA), are elevated in many malignant tumors compared to their benign tumor counterparts. Extracellular matrix degradation mediated by PA may facilitate tumor cell invasion and metastasis. To assess whether PA content correlates with the aggressive phenotype in prostate cancer, we studied these activators in the PC-3 human prostate cell line and PC-3CALN, an aggressive in vivo derived variant cell line. Enzymatic assays using H-D-val-leu-lys-pNA (S-2251) as substrate and peroxidase-anti-peroxidase immunohistochemical techniques were used. In an in vitro chemoinvasion assay, the PC-3CALN variant cell line demonstrated significantly greater invasive behavior than the unselected, parental PC-3 line. The activity of PA secreted by PC-3CALN cells was 3.5 times greater than that of PC-3 cells (p less than 0.01). PC-3 metastases obtained following intrasplenic injection of PC-3 cells had greater PA activities than the corresponding primary tumors. Immunohistochemical studies of PC-3 tumors demonstrated preferential localization of urokinase-type PA to areas of apparent tumor cell invasion. These data suggest a correlation between PA and the aggressive phenotype in this model of human prostate cancer. PA, in particular u-PA, may play a role in the migration and invasion of prostate cancer cells and provide a marker of the aggressive phenotype.
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PMID:Plasminogen activators in human prostate cancer cell lines and tumors: correlation with the aggressive phenotype. 265 23

Expression of plasminogen activator (PA) activity may be an important factor in the ability of tumour cells to metastasize; however, not all metastatic cells produce detectable PA activity. Conditioned culture media from revertant metastatic clones of cells derived by fusion of metastatic and non-metastatic rat mammary adenocarcinoma cells were found to contain a potent inhibitor of PA. This inhibited thrombin, human urokinase (UK) and tumour-derived PA, but not plasmin or trypsin. Inhibition was still obtained after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) of mixtures of PA and inhibitor, followed by development of PA activity on fibrin overlays. The PA inhibitor eluted from Sephadex G-200 over a broad M.wt. range (35,000-80,000) and was inactivated by heating to 70 degrees for 30 min. The appearance of inhibitory activity in the culture media was time-dependent and could be reduced by incubation of cells with cycloheximide. Because of these findings, the possible presence of inhibitors should be considered in investigations into the role of PA in the metastatic process.
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PMID:An inhibitor of plasminogen activator produced by tumour cell fusion hybrids. 293 23

We have carried out enzymatic, immunofluorescence, and surface iodination studies which show that B16 melanoma cells express the single chain form of the urokinase type plasminogen activator (uPA) on their cell surface, and that these cells are capable of plasminogen-dependent fibronectin degradation. The significance of the expression of surface single-chain uPA and uPA activity to the metastatic process was examined by preincubating melanoma cells with uPA modulating agents followed by i.v. injection of the cells into mice and enumeration of pulmonary nodules 17 days later. B16 cells that had been pretreated with anti-uPA immunoglobulins that were inhibitory to uPA activity invariably showed significantly decreased numbers of metastases compared to controls. On the contrary, pretreatment with plasmin, which is not only the product of the uPA catalyzed reaction but is also able to convert single-chain uPA to uPA, significantly increased the numbers of metastases. Control treatments, which included normal rabbit and mouse immunoglobulins, monovalent noninhibitory anti-uPA Fab fragments, and various monoclonal and polyclonal antibodies directed against other B16 cell surface antigens, did not affect the metastatic potential of the cells. Divalent inhibitory anti-uPA F(ab)2 fragments, on the contrary, inhibited metastasis as efficiently as intact IgG. The results support the hypothesis that proteolysis of extracellular matrix components by cell surface-localized uPA may be a critical step during the process of tumor cell invasion and metastasis.
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PMID:Modulation of metastatic potential by cell surface urokinase of murine melanoma cells. 296 89

Bis(5-amidino-2-benzimidazolyl)methane (BABIM) is a synthetic aromatic amidine compound which has a number of important biochemical effects, including inhibition of a family of esteroproteases (trypsin, urokinase, plasmin) previously linked to the complex process of tumor invasion. Previous work has suggested that exogenous natural protease inhibitors can block invasion of tumor cells across basement membranes (BM) in vitro. The authors studied the effect of BABIM on the human cell line HT-1080 with the use of a quantitative in vitro amnion invasion assay system. They have verified the ability of these cells to grow in nude mice and metastasize via the lymphatics or blood vessels on the basis of the route of administration of the inoculum. Cells which were able to actively cross the entire BM were trapped on filters and counted by both brightfield microscopy and by beta scintillation counting of cells whose DNA was labeled with tritiated thymidine. In agreement with either counting technique, BABIM, at a concentration of 10(-4) M, significantly inhibited invasion (P less than 0.005) over the 7-day course of the experiments. Under these conditions, the inhibitor was nontoxic and did not alter the attachment of the cells to the amniotic membrane. Furthermore, a highly significant inhibition of invasion (P less than 0.001) was also demonstrated across a variation in molar concentration of BABIM of more than 2 orders of magnitude. Most remarkably, cells were initially inhibited in their ability to invade in the presence of between 10(-9) and 10(-3) M BABIM. Measurement of Type IV specific collagenase in media from these cells shows a significant inhibition of activity in the presence of BABIM. These results suggest two, not necessarily exclusive, alternative interpretations: first, that inhibition of the proteolytic steps along the pathway of activation of basement membrane degrading enzymes results in inhibition of invasion; second, that arginine directed esteroproteases may work in concert with cellular collagenolytic metalloproteinases in the process of invasion by human tumor cells through native matrix barriers.
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PMID:In vitro inhibition of human sarcoma cells' invasive ability by bis(5-amidino-2-benzimidazolyl)methane--a novel esteroprotease inhibitor. 300 61

A 63-year-old female, who had undergone sigmoidectomy for sigmoid carcinoma one year before, was admitted for multiple liver metastases. A urokinase-immobilized catheter was introduced into the proper hepatic artery via the gastroepiploic artery operatively. A daily arterial infusion of 5-FU (250 mg) was combined with a weekly arterial infusion of adriamycin (30 mg) or MMC (10 mg). After discharge, 5-FU (200 mg/day) was given orally and MMC (10 mg) was infused intraarterially every other week at an outpatient clinic. ADR or MMC was infused with angiotensin II, known to increase arterial blood supply to a malignant lesion. Ultrasonography demonstrated 35 to 50% reduction in tumor diameter. The density of metastases seen in computerized tomography became low indicating tumor necrosis. Plasma CEA level, which had initially been as high as 864 ng/ml, decreased rapidly and has remained within normal limits up to the present time. Arterial infusion chemotherapy using 5-FU, ADR or MMC in combination with angiotensin II seems to be effective in the treatment of multiple hepatic metastases from colorectal carcinoma.
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PMID:[A case of multiple liver metastases from sigmoid carcinoma treated successfully with arterial infusion chemotherapy]. 308 78


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