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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Metalloproteinases secreted by tumor cells play an important role in metastasis. In the present study, we determined whether an inhibitor of these proteinases could inhibit the ability of tumor cells to degrade collagen and to metastasize. Metalloproteinases with degradative activities for type I collagen, type IV collagen, gelatin, and casein were secreted by a highly metastatic rat embryo cell line (4R) transfected by c-Ha-ras1 (also known as HRAS1). These metalloproteinases were identified by sodium dodecyl sulfate substrate-polyacrylamide gel electrophoresis as 92-kilodalton and 68-kilodalton gelatinolytic enzymes and 48-kilodalton and 45-kilodalton caseinolytic proteinases. A recombinant human tissue inhibitor of metalloproteinases (rTIMP) completely inhibited the proteolytic activities of these enzymes and was also a potent inhibitor of the proteolytic degradation of collagen by intact c-Ha-ras1-transfected cells. The ability of these cells to colonize the lungs after intravenous injection into nude mice was inhibited by 83% when rTIMP was repeatedly injected intraperitoneally into the animals. These data demonstrate that rTIMP is a potent inhibitor of the metalloproteinase activities of these cells and can also inhibit their metastatic potential.
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PMID:Inhibition of collagenolytic activity and metastasis of tumor cells by a recombinant human tissue inhibitor of metalloproteinases. 215 82

Orthotopic implantation of human colon carcinoma cells is useful for studying the behavior of metastatic subpopulations. We observed that the parental line and variants of human colon carcinoma KM12 cells were all tumorigenic following implantation into the subcutis or cecal wall of BALB/c nude mice. Their ability to metastasize to distant organ sites varied, however, with the site of growth. Subcutaneous (SC) tumors did not produce visceral metastases, whereas cecal tumors metastasized to the regional mesenteric lymph nodes and to the liver. To examine the influence of organ environment on the extracellular matrix-degrading activity of the tumors, we inoculated human colon carcinoma cells into the subcutis or cecal wall and after 7 weeks isolated and cultured the tumors in serum-free medium. The conditioned media of SC tumors contained very low levels of type IV collagenase (gelatinase) and heparanase (heparan sulfate-specific endo-beta-D-glucuronidase), whereas the media of the cecal wall tumors contained high levels of both. Zymograms of the media revealed that the intracecal human colon carcinomas secreted more than three times the amount of latent and active forms of 92-kd type IV collagenase than did the SC tumors. Moreover, only the conditioned media of intracecal tumors contained latent and active forms of 64-kd type IV collagenase. Histochemical analysis using rabbit antiserum raised against the synthetic peptides of 72-kd procollagenase type IV showed type IV collagenase in the intracecal tumors; human colon carcinoma growing SC, however, were not stained significantly. These results suggest that factors in the organ environment may affect production and secretion of tumor extracellular matrix-degrading enzymes, and these factors may modify the metastatic behavior of human colon carcinoma cells in nude mice.
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PMID:Influence of organ environment on extracellular matrix degradative activity and metastasis of human colon carcinoma cells. 225 Mar 3

Heparan sulfate (HS) enhanced the growth of the highly metastatic (HM) 3LL cell line, but not that of the low metastatic (LM) counterpart, in a dose-dependent way. Heparin, chondroitin sulfate, hyaluronate did not produce this effect. At 4 degrees C both cell lines exhibited high affinity binding sites (Kd 10(-8) M) for exogenous HS. Unlike LM cells, the HM ones lost half of the surface-bound HS during the 24-hour incubation at 37 degrees C. HM cells in the exponential growth phase took up the bound HS at lower rate than the LM counterparts. Both cell lines fragmented the exogenous HS intracellularly, but only the HM cells were able to degrade it at the cell surface. The HM cells contained much more heparin-binding proteins--especially in the cell membrane and nuclear fraction--than the LM ones. These results clearly demonstrate that the interactions of tumor cells with exogenous HS are influenced by the invasive phenotype. We suggest also that there could be a correlation between the surface degradation, the slow uptake and the growth-promoting effect of the exogenous HS.
Invasion Metastasis 1990
PMID:Interactions of exogenous heparan sulfate with tumor cells of different metastatic phenotype. 222 18

The fibroblast growth factors (FGFs) are a family of polypeptide growth regulators. The prototypes of this family are acidic and basic FGF. Unusual among their characteristics are a high affinity for the glycosaminoglycan heparin and the lack of a signal sequence for secretion. Other members of the FGF family include a number of oncogene products that also display heparin affinity but do possess signal sequences. Results from early tissue culture studies were consistent with the prediction that acidic and basic FGF would not be secreted. Investigators found that virtually no FGF was secreted into conditioned media, instead it remained cell-associated and was deposited into the basement membrane. More recently, however, a number of studies have indicated that a small amount of FGF is 'released' from cells where it is postulated to act as an autocrine regulator. Acidic and basic FGF have been localized in basement membranes both in vivo and in vitro. The mode of release to this site is also unclear but may be secondary to the mechanisms cited above with soluble FGF becoming bound to heparan sulfate molecules in the extracellular matrix. A number of observations have indicated that matrix-bound FGF is biologically active in vitro. There are no data to indicate whether the same is true for FGF bound to basement membranes in vivo. In addition to its apparent sequestration in the basement membrane, FGF has also been localized to the surface of a variety of normal and tumor cell types. In particular, endothelial cells have been shown to possess two classes of FGF-binding sites: low abundance, high-affinity receptors that mediate the biological activity as well as high abundance, low affinity binding sites. The physiologic relevance of FGF binding to these low affinity sites is not clear. The possibility of locally high concentrations of heparin released by mast cells, as well as the presence of heparan sulfate-degrading enzymes, suggests that this glycosaminoglycan bound FGF might be released from these binding sites under some circumstances. Cell surface binding of FGF has also been demonstrated in vivo; in rabbits plasma levels of the growth factor were shown to be dramatically elevated following intravenous heparinization. Since the FGFs were first noted to lack a signal sequence, cell injury has been suspected to be the most likely route for FGF release in vivo. A number of studies using different models of cell injury, including endotoxins and irradiation, have revealed that damaged cells do release FGF.(ABSTRACT TRUNCATED AT 400 WORDS)
Cancer Metastasis Rev 1990 Nov
PMID:Modes of FGF release in vivo and in vitro. 229 37

There is only one previous report of an estrogen-secreting adrenal tumor occurring in a woman during reproductive years. Our patient presented with mild hirsutism associated with menstrual bleeding every 3-6 weeks. The occurrence of apparently intermenstrual bleeding prompted an evaluation of estrogen levels. Markedly elevated plasma estrone levels were found (860-2305 pmol/L; normal, 50-340). Lesser relative elevations in 11-deoxycortisol and androstenedione were noted. Computed tomographic scanning of the adrenal glands identified a large tumor, which was subsequently resected. Estrone levels fell to 120 pmol/L, and all other abnormalities were corrected. Eighteen months after adrenalectomy, ovulation occurred regularly, and steroid levels were entirely normal. Steroid production in a cell suspension made from tissue obtained from the 190-g tumor was compared with that occurring in normal human adrenal cells. The production of estrone by the tumor cells was 40-fold greater than that by normal adrenal cells. There was also a mild excess of 11-deoxycortisol produced by tumor cells, but the tumor cells were less than 50% as efficient as normal cells in producing cortisol, dehydroepiandrosterone, androstenedione, testosterone, and dehydroepiandrosterone sulfate. Examination of the steroid profile in plasma occurring in three other patients with adrenal tumors reveals that while elevations in estrone occur frequently, this is usually due to the peripheral conversion of very high levels of androstenedione. Estrone, androstenedione, and 11-deoxycortisol plasma levels were elevated in all four patients; dehydroepiandrosterone sulfate was elevated in only two of four patients. After resection of one of these tumors, all steroid levels remained normal despite the occurrence of extensive metastases. These observations confirm the difficulty of making a diagnosis of estrogen excess in a woman during reproductive years because of the paucity of physical signs. The acquisition of aromatase activity was clearly demonstrated by tumor cells from our patient in vitro. Elevated plasma concentrations of estrone, androstenedione, and 11-deoxycortisol provide useful markers for adrenal tumors, but no one steroid can be relied upon in all tumors, and metastases may lack the steroidogenic capabilities of the primary tumor.
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PMID:Steroidogenesis in an estrogen-producing adrenal tumor in a young woman: comparison with steroid profiles associated with cortisol- and androgen-producing tumors. 229 37

Experiments were performed to determine the relative effects of glycosaminoglycans and extracellular matrix components alone or in association with various substrates, including extracellular matrix, on the proliferation of rat rhabdomyosarcoma (RMS) cell lines of different metastatic potential and nontumorigenic rat myoblast L6 cells. The assays used various substrates: tissue culture plastic, type I and IV collagen, fibronectin, laminin and extracellular matrix deposited by corneal endothelial cells. In control experiments, tumor cells grew faster on fibronectin and extracellular matrix than on the other substrates, and their proliferation rate was decreased slightly by laminin. Collagens were growth-inhibitory only for the highly metastatic line. The proliferation rate of L6 myoblasts was not greatly affected by the different substrates. The addition of exogenous glycosaminoglycans to the culture medium modified cell proliferation on the various substrates. Heparin inhibited the growth of all the cell lines tested, independent of the substrate. When cultured on laminin substrate the proliferation rates of the cell lines were depressed by addition of heparan sulfate to the medium, and this effect was more pronounced in the metastatic RMS lines. Chondroitin sulfate and dermatan sulfate enhanced the growth rates of the tumorigenic cells when cultured on collagen type I surfaces. Hydrocortisone, which induces myogenic differentiation, decreased the cell proliferation rates of all the cell lines tested and intensified the inhibitory effects of heparin when added simultaneously to the culture medium. The results showed that glycosaminoglycans and other matrix components can affect the proliferation rates of rhabdomyosarcoma cell lines.
Clin Exp Metastasis
PMID:Effects of glycosaminoglycans and extracellular matrix components on metastatic rat rhabdomyosarcoma tumor and myoblast cell proliferation. 239 Aug 14

The pattern of melanoma-associated antigens (MAAs) expressed on the surface of melanoma cells in 23 metastases, 15 obtained from different patients and 8 from different metastases in two patients, was studied by immunoprecipitation and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis using monoclonal and polyclonal melanoma antisera. Though there were differences in the MAAs expressed by each melanoma, there were marked similarities as well. No more than two melanomas had a similar pattern of MAAs. However, all melanomas expressed some MAAs, and most MAAs were commonly expressed by several melanomas. Two of the MAAs studied, with molecular weights of approximately 75,000 and 95,000 to 97,000, were particularly well represented, and at least one of these two antigens was expressed by all melanoma cells. These results suggest that complete absence of tumor-associated antigens on metastatic melanoma cells is a rare phenomenon. All melanoma lines we studied expressed at least one of a restricted number of antigens. Thus despite antigenic heterogeneity, sufficient similarity remains between different melanomas to permit specific immunotherapy to be targeted to a limited number of tumor antigens.
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PMID:Immunophenotype of human melanoma cells in different metastases. 241 93

Since June 1979, the authors have had the opportunity to treat a renal homograph recipient who developed primary embryonal cell testicular carcinoma with retroperitoneal and pulmonary metastases. This patient was treated with an induction chemotherapy protocol of vinblastine sulfate, bleomycin, and cisplatin and has remained free of disease through June 1985, without loss of his renal homograph. Cisplatin-based cytoxic drug therapy can be delivered safely to a renal transplant recipient without causing kidney damage, and, in this case, achieved a cure of metastatic testicular cancer.
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PMID:Curative, platinum-based cytoxic drug therapy in a renal transplant recipient with metastatic testicular cancer. 242 86

Vitronectin, also known as serum-spreading factor or S-protein, mediates cell adhesion and inhibits formation of the membrane-lytic complex of complement and the rapid inactivation of thrombin by antithrombin III in the presence of heparin. Vitronectin is normally present in plasma at a concentration of approximately 300 micrograms/mL. The investigators quantified plasma vitronectin with an enzyme-linked immunosorbent assay and visualized reduced and nonreduced vitronectin by immunoblotting after separation of plasma or serum by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The concentration of plasma vitronectin was markedly reduced in some patients with disseminated intravascular coagulation, especially in those with liver failure; it was near normal in patients with metastatic cancer and acute leukemia. Patients with vitronectin levels less than 40% normal invariably had low fibrinogen and antithrombin III and a prolonged prothrombin time. In both normal and patient plasmas there was heterogeneity in the ratio of the 75,000- and 65,000-mol wt polypeptides of reduced vitronectin: 18% had mostly the 75,000-mol wt polypeptide, 59% had roughly equal amounts of the two polypeptides, and 22% had mostly the 65,000-mol wt polypeptide. This polymorphism is inherited and appears to be due to two alleles that are present with approximately equal frequency. The blotting patterns of vitronectin in reduced and nonreduced plasmas were largely unaltered in plasma of patients with defibrination syndrome, fibrinolysis, liver failure, sepsis, metastatic cancer, and acute leukemia. There was no evidence of fragmentation of vitronectin or formation of the disulfide-bonded complex of vitronectin and thrombin-antithrombin III that is found when blood is clotted. Thus these results corroborate in vitro observations that the liver is the major source of plasma vitronectin, suggest that vitronectin may become depleted during disseminated intravascular coagulation, and define a genetic polymorphism of vitronectin.
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PMID:Plasma vitronectin polymorphism in normal subjects and patients with disseminated intravascular coagulation. 245 67

Increased--GlcNAc beta 1-6Man alpha 1-6Man beta--branching in asparagine-linked oligosaccharides has been observed in murine and human tumor cells and has recently been linked to enhanced metastatic potential in experimental tumor models. Leukoagglutinin (L-PHA) requires the beta 1-6-linked lactosamine antenna (beta 1-6 branch) for high affinity binding and was used in this study to quantitate these structures on glycoproteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Normal rodent tissues and cell lines were used to standardize the experimental conditions required to quantitate beta 1-6-branched oligosaccharide structures and the glycosyltransferase activity which initiates the synthesis of the antenna, beta 1-6 N-acetylglucosamine (GlcNAc)-transferase V (EC 2.4.1.155). Secondly, the levels of L-PHA-reactive oligosaccharide were compared in a series of benign and malignant human breast biopsies. Normal human breast tissue and benign lesions showed low expression but 50% of the primary malignancies examined showed significantly elevated L-PHA reactivity. GlcNAc transferase V activities in the human breast carcinomas and in normal murine tissues correlated with the levels of L-PHA reactive oligosaccharide in the tissues. GlcNAc transferase V showed similar ranges of activities, differing by approximately 5-fold between high and low expressing mouse tissues; fibroblasts with and without an activated H-ras oncogene; and low and high expressing human breast carcinomas. The results show that beta 1-6 branching in asparagine-linked oligosaccharides is dependent on tissue-specific regulation of GlcNAc transferase V activity. Secondly, a subset of human breast malignancies showed elevated levels of beta 1-6-branched oligosaccharides compared to benign samples, suggesting that further studies are warranted to determine whether the presence of these oligosaccharides is associated with metastatic disease and reduced patient survival time.
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PMID:Oncodevelopmental expression of--GlcNAc beta 1-6Man alpha 1-6Man beta 1--branched asparagine-linked oligosaccharides in murine tissues and human breast carcinomas. 252 56


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