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

Because of certain analogies between the spread of tumors and different steps of pregnancy culminating in egg implantation and invasive growth, pregnant mice were treated at different intervals post coitum with two thrombocytopenic agents which can reduce metastases by interfering with vascular lodgement and growth of tumor cells. It was found that both neuraminidase and antiplatelet serum were active against pregnancy, the enzyme being by far the more effective of the two. The mechanism of this effect involves both egg implantation and egg development. The effect cannot be explained solely by the thrombocytopenia produced by both agents.
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PMID:Total suppression of pregnancy in mice by post-coital administration of neuraminidase. 528 22

A panel of fluorescein-conjugated lectins was used to investigate the cell surface carbohydrates of cell lines isolated from a mouse mammary adenocarcinoma which differ markedly in their morphological and metastatic properties. The lectin-binding profiles of the cells showed them to express generally similar cell surface characteristics; however, two minor differences were evident. Galactose moieties recognized by peanut lectin were expressed on all highly metastatic fusiform cell types examined, but only on 50-60 per cent of the polygonal cells of limited metastatic capacity. Similarly, N-acetylgalactosamine moieties were demonstrated on fusiform cell types by soya bean lectin binding but were not expressed on intact polygonal cells. In both cases pretreatment of polygonal cells with neuraminidase allowed lectin binding comparable with that of fusiform cells suggesting that Gal and GalNAc sugars were abundantly present but masked by sialic acid residues. Using a novel technique in which tumour cells were incubated on cryostat sections of normal tissues, it was found that the cell lines exhibited different adhesion patterns which to some extent reflected their preferential sites for spontaneous metastasis and organ colonization in vivo. Thus the adherence of fusiform cells to liver was five times as great as that of polygonal cells, whereas the latter bound preferentially to lung tissue. Prior treatment of polygonal cells with neuraminidase doubled their frequency of attachment to liver sections, but had no effect on their binding to other tissues. Also, the presence of 100 mM N-acetylgalactosamine during incubation specifically inhibited the adherence of fusiform cells to liver tissues, but did not significantly influence other cell-tissue interactions. The data suggest that the expression of galactosyl or N-acetylated galactosyl groups on the fusiform cells facilitates their attachment to lectin-like receptors on liver cells and contributes to their superior capacity, compared with polygonal cells, for growth and metastasis in this organ.
Clin Exp Metastasis
PMID:Studies of mammary carcinoma metastasis in a mouse model system. II: Lectin binding properties of cells in relation to the incidence and organ distribution of metastases. 654 7

When the tumor-bearing leg of C57BL/6J mice was amputated 16 days after SC inoculation of 10(6)B16 melanoma cells, all the amputated mice died of pulmonary metastases. Transfer of lungs from the amputated to normal syngeneic mice revealed tumor cells in the lungs just after amputation. Repeated weekly injections of BCG and irradiated tumor cells, beginning 24 h after amputation of the tumor-bearing limb, prolonged the survival only of mice presensitized to BCG. Injections of BCG or irradiated melanoma cells alone, or neuraminidase- and mitomycin C-treated tumor cells or of Levamisole had no effect, but injections of ConA-coated tumor cells slightly prolonged the survival of the amputated mice. Both BCG and B16 cells induced humoral and cell-mediated immunity but there was no cross-reactivity between BCG and B16 cells.
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PMID:Inhibition of pulmonary metastases of B16 melanoma with irradiated tumor cells and BCG. 655 7

Inevitable metastatic disease was partially controlled in Wistar/Furth rats after intraperitoneal injection of blood lymphocytes cultured with neuraminidase-treated tumor cells and phytohemagglutinin after amputation of implanted syngeneic MT/W 449A mammary adenocarcinoma. Control of MT/W 449A metastasis was limited to animals with primary tumors weighing less than 700 mg. An optimal 20-25 X 10(6)-lymphocyte dose gave control in 8 of 18 animals (44%). Metastasis control rate was 50% in animals with small primary tumors (less than 250 mg). All animals in different control groups died of metastatic disease, without significant survival differences among overall groups or tumor weight-stratified subgroups. Intraperitoneal injection of neuraminidase-treated tumor cells alone did not control metastatic disease. Cell-mediated 51Cr-release cytotoxicity indexes of test inocula were significantly predictive of longevity and survival.
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PMID:Metastasis control by injection of blood lymphocytes cultured with neuraminidase-treated MT/W 449A rat mammary carcinoma. 670

A clone of B16 malignant melanoma cells with a preference for metastasis to the liver was isolated and characterized. The parent tumor cells (F1) were injected in the tail vein of C57BL/6 mice, and the resultant liver colonizing cells were isolated and then subcultured for two to three weeks. The cells were then reinjected into the next series of mice. After five such passages, a clone (L4) of melanoma cells was obtained that metastasized almost exclusively to the liver. A hepatic binding protein (HBP) was isolated from rabbit liver that agglutinated neuraminidase-treated F1 and L4 malignant melanoma cells. Different agglutination titers found between the parent and liver-metastasizing clone demonstrated differences in cell-surface properties between the parent tumor and the liver-metastasizing clone. These results demonstrate that malignant melanoma cells can be selected for preferential liver metastasis and can be recognized and agglutinated by specific HBPs. Metastasis from human uveal malignant melanoma may occur by similar mechanisms.
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PMID:Metastatic choroidal melanoma. Hepatic binding protein reactivity toward a liver-metastasizing clone. 684 70

Platelets are required for certain experimental tumor metastases and several lines of tumor cells have been shown to aggregate platelets. We have extracted a sedimentable sialolipoprotein, platelet aggregating material (PAM) from the cell surface of SV40 transformed Balb C3T3 fibroblasts which aggregates heparinized PRP at 2.5 micrograms/ml via the release reaction, following a one minute lag period. A similar extract from non-transformed 3T3 cells has barely measurable activity at 40 micrograms/ml. Gel-filtered platelets (GFP) do not aggregate with PAM. However, PAM aggregation can be restored by addition of 5% plasma but not by fibrinogen. Two plasma components are required: a heat-labile complement component which is activated during the lag period; and a heat-stable factor which is required for platelet aggregation. The pathophysiologic significance of PAM has been examined in ten variant cell lines derived from a spontaneously metastatic renal cell sarcoma of rats, initially induced with polyoma virus (PW20 Wistar-Furth parental lines). These lines were selected in vitro and in vivo from a single line and differed in their capacity to form distant tumors in various organs after subcutaneous injection. These cells were examined for cell surface sialylation, PAM and PAM sialic acid content, since cell surface sialic acid is increased in a variety of tumor tissues and PAM is inhibited by neuraminidase. A good correlation was obtained between in vivo metastatic potential and cell surface sialic acid, r = 0.83, p less than 0.003; cell surface sialic acid and PAM, r = 0.85, p less than 0.002; in vivo metastatic potential and sialic acid content of PAM, r = 0.69, p less than 0.03; and in vivo metastatic potential and PAM, r = 0.68, p less than 0.03. We conclude that platelets may play a role in hematogenous metastasis via the ability of tumor cells to aggregate platelets by cell surface constituents containing sialic acid. The platelet-tumor cell interaction requires activation of the alternate complement pathway and a heat stable plasma factor.
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PMID:Platelet aggregating material (PAM) of two virally-transformed tumors: SV3T3 mouse fibroblast and PW20 rat renal sarcoma. Role of cell surface sialylation. 711 9

A murine melanoma variant (B16-F10ir6), resistant to lymphocytic cytolysis, has been shown previously to produce lower numbers of tumor nodules in the lung of C57BL/6J mice following i.v. inoculations. These differences found in tumor implantation and lymphocyte recognition may be due to changes in surface properties of this cell line. Therefore, membrane-bound sialic acid (released by Vibrio cholerae neuraminidase treatment), ectosialyltransferase activity, and total cellular glycosidase levels were measured in this cell line and compared with levels in its parent melanoma tumor cell line, B16-F10, which was selected for its enhanced ability to form tumor nodules. The results of these studies indicate a correlation between the degree of lung implantation and the amount of tumor cell sialic acid accessible to neuraminidase cleavage, tumor cell surface sialyltransferase activity, and several cellular glycosidase activities. These results are consistent with the idea that membrane structural changes in the glycocalyx may account for the ability of a tumor cell to implant and metastasize.
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PMID:A correlation between cell surface sialyltransferase, sialic acid, and glycosidase activities and the implantability of B16 murine melanoma. 723 26

Platelets are required for certain experimental metastases. Several lines of animal tumor cells aggregate platelets in vitro and in vivo. Previous studies with one of these lines, an SV40-transformed 3T3 mouse fibroblast (SV3T3) have revealed that the platelet-aggregating material is an extractable membrane-associated sialolipoprotein which requires divalent cation, complement, and a heat-stable plasma component for activity. Little information is available on the interaction of human tumors with platelets. We now report on the ability of two human adenocarcinomas of the colon (LoVo and HCT-8) and an anaplastic mouse tumor (Hut-20) to aggregate platelets by a different mechanism, the generation of thrombin. These spontaneous cell lines aggregate human or rabbit platelet-rich plasma after a 1- to 2-min lag period. This is often followed by a visible clot. Unlike SV3T3 cells, aggregation by LoVo, HCT-8, and Hut-20 cells is not inhibited by neuraminidase, trypsin, or cobra venom factor. These three cell lines markedly shorten the recalcification time of citrated plasma, whereas SV3T3 cells do not. Phospholipase A2 treatment inhibits the shortening of the recalcification time for the three tumors; this parallels its inhibitory effect on platelet aggregation. LoVo, HCT-8, and Hut-20 cells generate thrombin via the "tissue factor" coagulation pathway (using coagulation factor-deficient substrates). Dansylarginine-N-(3-ethyl-1,5-pentanediyl)amide, a highly specific, potent antithrombin antagonist, inhibits LoVo-, HCT-8-, and Hut-20-induced platelet aggregation at 4 to 15 microM, whereas its effect on SV3T3 cells is negligible. If platelets are required for certain human tumor metastases, dansylarginine-N-(3-ethyl-1, 5-pentanediyl)amide, or other antithrombin agents, may prove to be valuable therapeutic agents.
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PMID:Inhibition of the platelet-aggregating activity of two human adenocarcinomas of the colon and an anaplastic murine tumor with a specific thrombin inhibitor, dansylarginine N-(3-ethyl-1,5-pentanediyl)amide. 730 74

Two lines of mouse tumor cells were shown to be capable of aggregating mouse and rabbit platelets in vitro. This process required higher Mg2+ concentrations than were needed by other commonly used platelet-aggregating agents. Platelet-aggregating activity was also found in tumor cell membrane fragments. This membrane-bound platelet-aggregating material contained protein, lipid, and carbohydrate moieties. The presence of all three appeared to be essential for stimulating platelet aggregation. Destruction of any component abolished its activity: protein by trypsin; lipid by phospholipase A2 and non-ionic detergents; and sialic acid by neuraminidase. Platelet aggregation induced by tumor cell membrane fragments was associated with a secretory release reaction. In this process, growth-promoting activity for tumor cells was also released from platelets. These results underline the importance of platelets in establishing tumor metastases.
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PMID:Characterization of the platelet-aggregating activity of tumor cells. 735 51

The OPAR mouse monoclonal antibody (mAb) directed against rat hepatocytes was previously shown to inhibit adhesion of TA3/Ha mammary carcinoma cells to hepatocytes. The antigen is abundantly present at the surface of hepatocytes beneath the endothelium of liver capillaries where we have observed invasion of carcinoma cells to occur. The OPAR mAb reacted with three major bands on a Western blot of liver plasma membrane proteins. The same proteins were also seen upon immunoprecipitation from iodinated liver plasma membrane proteins. We have isolated OPAR antigens by lectin wheat germ agglutinin (WGA) and OPAR affinity chromatography. Amino acid sequence analysis revealed that two of the bands were alpha 1-macroglobulin and C4-binding protein, which are serum components produced by hepatocytes. The presence of the epitope on distinct proteins and our previous observation that it can be detected in the Golgi apparatus but not in the endoplasmic reticulum, suggested that OPAR reacts with a liver-specific glycoconjugate. Loss of OPAR reactivity after neuraminidase and N-glycosidase F treatment showed that the epitope contains sialic acid residues on N-linked sugar moieties. OPAR also reacted with rat fibronectin, and inhibited adhesion of TA3/St cells to fibronectin. This explains the inhibition by the OPAR mAb of TA3/St cell adhesion to hepatocytes, which we have shown to be due mainly to interaction with hepatocyte surface-associated fibronectin. However, adhesion of the related TA3/Ha cells to hepatocytes, which is mediated by the alpha 6 beta 4 integrin, and does not involve binding to fibronectin, is also inhibited. This suggests that alpha 6 beta 4 on liver-metastasizing carcinoma cells binds to an OPAR epitope-carrying glycoprotein produced by hepatocytes.
Clin Exp Metastasis 1995 Jan
PMID:Adhesion of carcinoma cells to rat hepatocytes and rat fibronectin is inhibited by the OPAR monoclonal antibody, which is directed against a rat liver-specific carbohydrate epitope. 752 66


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