Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasma membranes isolated from Yoshida ascites hepatoma AH-130 by a modification of the method of T.K. Ray (Biochim. Biophys. Acta 196:1, 1970), were subfractionated into three fractions having densities (d) 1.12, 1.14 and 1.16 by discontinuous sucrose density-gradient. Membrane subfractions were characterized by electron-microscopy, by assay of marker enzymes and by lipid composition. All subfractions appeared to be essentially free from whole mitochondria, lysosomes and nuclei. Subfraction d 1.16 had the highest 5'-nucleotidase, Mg++-ATPase and (Na+ +K+)-ATPase activities; cytochrome c oxidase was undetectable in any fraction and glucose-6-phosphatase was measurable only in fraction d 1.14 and 1.16. Cyclic AMP phosphodiesterase was nearly equally distributed in the fractions. Adenylate cyclase, 5'-nucleotidase and Mg++-ATPase activities of tumor membrane were lower with respect to liver plasma membrane, while cyclic AMP phosphodiesterase and (Na" +K+)-ATPase were found to have similar activities in the two membrane preparations. With respect to liver membrane, hepatoma membrane contained a higher amount of glycolipids and a higher amount of phospholipids accounted for mainly by sphingomyelin, phosphatidylserine and phosphatidic acid. The possible significance of the decrease of adenylate activity in the hepatoma membrane is briefly discussed.
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PMID:Isolation and characterization of the plasma membrane from Yoshida hepatoma cells. 16 55

Sodium cyanate at a dose level of 125 or 250 mg/kg i.p. caused an inhibition of incorporation of 3H-labeled amino acids into cytoplasmic and nuclear proteins of the rapidly growing hepatoma 7777 and the slowly growing hepatoma 9618A. There was no inhibitory effect on 3H-labeled amino acid incorporation into protein in the livers of rats bearing these tumors. Studies on the effects of sodium cyanate on incorporation of 3H-labeled amino acids into total acid-insoluble material indicated that a greater than 85% inhibition could be achieved in hepatoma 5123C, hepatoma 9618A2, and the MK3 kidney tumor with either little or no effect in host liver, kidneys, brain, skeletal muscle, intestinal mucosa, and regenerating liver after partial hepatectomy.
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PMID:Tumor-selective inhibition of the incorporation of 3H-labeled amino acids into protein by cyanate. 16 51

Nuclear proteins of rat liver and rat ascites hepatoma were fractionated by extraction in solutions of different salt concentration and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The difference between the electrophorograms of the different fractions of nuclear proteins isolated from liver and from hepatoma was found in the bands which have the same electrophoretic mobility as the main proteins of informofers and are extracted from nuclei at salt concentrations which extract informofers. These changes in the electrophoretic patterns of proteins with the solubility and mobility of the proteins of informofers could be related to the defective processing of heterogeneous nuclear RNA in the hepatoma. In addition the identity of electrophorograms of nuclear proteins isolated from liver and from hepatoma and the identity of most bands in the electrophorograms of nuclear proteins which are soluble in 0.35 M NaCl and chromosomal proteins which are not soluble at this salt concentration support the notion that these nonhistone nuclear proteins which can be identified as the major bands in electrophorograms of chromosomal proteins are not the specific regulators of gene expression.
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PMID:Nuclear proteins of rat liver and of an aminoazo-dye-induced hepatoma. 16 62

Using precipitating antibodies to ACI rat liver ferritin and to sodium-dodecyl-sulfate-dissociated protein subunits of ACI rat liver ferritin, we have demonstrated the presence of ferritin-positive sites and subunit-positive sites in situ in several rat hepatoma cell lines by immunofluorescence. Hepatoma cells from three transplantable rat hepatomas (Reuber H-139, Reuber H-35, and Morris 5123) were explanted and propagated. Rabbit antibodies specific for either protein subunits of ferritin or ferritin were prepared by affinity chromatography or by dissociation of antibody-antigen complexes with 0.1 M acetic acid followed by differential ultracentrifugation. Explants of Reuber H-139, Reuber H-35, and Morris 5123 hepatoma cells, grown either in ordinary McCoy's 5a medium or in such medium enriched with iron (0.002% Fe), gave positive immunofluorescence for subunits as well as ferritin. Exposure of a clonal strain of Morris 5123 hepatoma cells to iron-enriched culture medium for varying lengths of time of up to 24 hours resulted in progressive increase in the quantity of ferritin-specific immunofluorescent cytoplasmic material, which was at first present diffusely, and later in clumps. By contrast, during the initial 24-hour period, subunit-specific immunofluorescence remained at relatively low intensity, with diffuse distribution through the cytoplasma. Our findings indicate a) the presence, in the cytoplasm, of the three kinds of hepatoma cells, of unassembled or only partly assembled subunits of fragments of subunits as well as of ferritin, and b) rapid assembly of the protein subunits into apoferritin and ferritin after administration of iron, so that the concentration of subunits in the cytoplasm was not significantly increased.
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PMID:Production of ferritin by rat hepatoma cells in vitro. Demonstration of protein subunits and ferritin by immunofluorescence. 16 99

Guinea pig T lymphocyte proliferation induced by sodium periodate (NaIO4) or neuraminidase-galactose oxidase (NG) occurs when lymphocytes and macrophages are cultured together after treatment of either purified T lymphocytes or macrophages with these agents. Regardless of which cell initially bears the modified surface carbohydrate, lymphocyte proliferation requires the presence of viable homologous macrophages and fails to occur when they are replaced with fibroblasts, erythrocytes, L2C leukemia cells, thymocytes, PMN, line I hepatoma cells, or murine macrophages. Lymphocyte proliferation resulting from NaIO4 or NG treatment of lymphocytes is diminished when these cells are treated with proteolytic enzymes or aged in in vitro culture for 48 hr. By contrast, proteolytic enzyme treatment or in vitro aging has no effect on the ability of NaIO4 or NG-treated macrophages to induce lymphocyte proliferation. The requirement for macrophage-lymphocyte interaction in NaIO4 or NG-induced lymphocyte proliferation is indicative of a central role for the macrophage in the initiation of T lymphocyte proliferation.
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PMID:The requirement for macrophage-lymphocyte interaction in T lymphocyte proliferation induced by generation of aldehydes on cell membranes. 17 Mar 38

The contributions of nuclear populations to the total profile of nuclear proteins in a tissue were examined in normal rat liver and Morris hepatoma 7777. Comparison by sodium dodecyl sulfate polyacrylamide gel electrophoresis of phenol-soluble nuclear proteins from tumor and control liver revealed additional proteins of molecular weight 60,000, 100,00, and 135,000 and the loss of proteins of about 45,000 and 55,000 in the tumor. Subfractionation of liver nuclei on a 30 to 50% sucrose gradient yielded three nuclear classes with nearly identical complements of the phenol-soluble proteins. Similar fractionation performed on the hepatoma nuclei also produced three nuclear populations. In the hepatoma nuclei, several differences in the phenol-soluble proteins were found between the minor, slowly sedimenting nuclear fraction, and the two major fractions, while the two latter fractions were very similar in their protein composition. Histones derived from both tissues were also compared electrophoretically, indicating a decrease in the concentration of histone H1(0)in all nuclear classes derived from the tumor.
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PMID:Fractionation of nuclei and analysis of nuclear proteins of rat liver and Morris hepatoma 7777. 17 Oct 58

Nuclei prepared from host liver and from Morris hepatomas 7777 and 7800 have been compared with respect to some of their biochemical characteristics. Several criteria were used to ensure that liver and hepatoma nuclei were of equal purity. These criteria include equal specific activity ratios (homogenate nuclei) for several marker enzymes. Phospholipids, proteins, and sialic acid content were compared in liver and hepatoma sucrose nuclei and in membrane and chromatin fractions obtained from liver or hepatoma nuclei. As determined by sodium dodecyl sulfate polyacrylamide electrophoresis, the only qualitative difference in protein that could detected was in 2 of the 4 nuclear fractions. There was an extra band in each of the 2 hepatoma fractions. Sialic acid was increased in hepatoma nuclei. In addition, a fraction containing most of the inner nuclear membrane from liver nuclei had no sialic acid, whereas the equivalent hepatoma fraction did have sialic acid. Total phospholipids were increased in hepatoma nuclei. This increased phospholipid concentration in hepatoma nuclei as compared to liver nuclei was apparent with sucrose nuclei, citric acid nuclei, membrane-denuded nuclei, chromatin, and nuclear fractions. Determination of the percentages of individual phospholipids making up the total phospholipids extracted revealed that the only significant change in the phospholipid composition of hepatoma nuclei was an increase in sphingomyelin. A large amount of this sphingomyelin was found to be associated with chromatin. The possible significance of chromatin-associated phospholipids is discussed.
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PMID:Some biochemical characteristics of rat liver and Morris hepatoma nuclei and nuclear membranes. 17 Oct 64

High levels of a novel vitamin B12-binding protein (hepatoma B12 BP) have been observed recently in plasma obtained from three adolescent patients with hepatocellular carcinoma. This protein has now been isolated in homogeneous form from the plasma and pleural fluid of two of these patients by the use of affinity chromatography with vitamin B12-Sepharose. The hepatoma B12 BP belongs to the R-type group of B12-binding proteins and is essentially indistinguishable from the recently isolated human milk and saliva R-type proteins in terms of: (a) immunologic properties based on immunodiffusion and immunoprecipitation assays; (b) amino acid composition; (c) molecular weight based on amino acid and carbohydrate content; and (d) absorption spectra. Both hepatoma B12 BPs contain more sialic acid and less fucose than the milk and saliva B12 BPs. All four proteins contain similar amounts of galactose, mannose, galactosamine, and glucosamine. Differences in sialic acid content appear to account for the differences in electrophoretic mobility that were observed among the four proteins. Differences in total carbohydrate content appear to account for the differences in apparent molecular weight that were observed with both gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Tumor tissue from one of the patients contained 10 times as much R-type protein as did normal liver tissue from the same patient. This suggests, although it does not prove, that synthesis by the tumor is the cause of the high levels of R-type protein found in the plasma of certain patients with hepatocellular carcinoma. Plasma survival studies performed with rabbits indicate that the hepatoma B12 BP has a prolonged plasma survival and suggests that his parameter is also of importance.
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PMID:Isolation and characterization of a novel vitamin B12-binding protein associated with hepatocellular carcinoma. 17 Dec 83

Sodium-23 magnetic resonance was performed on four types of cancers and six types of normal tissues of rats and mice. The spin-lattice relaxation time of the tumors was generally longer than that of the normal tissues, with the most marked difference occurring between rat liver (T1 = 6.5 msec) and Novikoff hepatoma (T1 =23.7 msec). Estimation of tissue sodium from the signal intensity of the resonance indicated that all four types of tumors contained more sodium than any of the normal tissues.
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PMID:NMR in cancer. VII. Sodium-23 magnetic resonance of normal and cancerous tissues. 17 89

Glutamine-dependent carbamyl phosphate synthetase [EC 2.7.2.9] was purified 1,300-fold from rat ascites hepatoma cells (AH 13) as a multienzyme complex with aspartate transcarbamylase[EC 2.1.3.2] and dihydroorotase[EC 3.5.2.3], using dimethyl sulfoxide, glycerol, and dithiothreitol as stabilizers. The purified complex was essentially homogeneous on agarose-acrylamide composite gel electrophoresis and analytical ultracentrifugation. Its molecular weight was estimated to be about 870,000 by sedimentation equilibrium studies. After alkylation with iodoacetamide or reduction with 0.6% dithiothreitol at 100 degrees, the complex gave a single band on polyacrylamide gel electrophoresis in sodium dodecyl sulfate in a position corresponding to a molecular weight of 210,000. These results indicate that the complex consists of four subunits of similar size.
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PMID:Purification of homogeneous glutamine-dependent carbamyl phosphate synthetase from ascites hepatoma cells as a complex with aspartate transcarbamylase and dihydroorotase. 17 92


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