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

Mitochondria isolated from normal liver, experimental hepatoma, and Krebs II ascites tumor tissues in mice were examined by isopycnic centrifugation in a sucrose density gradient (25--50%). Normal liver mitochondria were shown to be characterized by two visible zones, while those of tumors were distributed homogeneously. Such a distribution pattern was also confirmed by the investigation of marker enzyme activities (glucose-6-phosphatase and cytochromoxidase). A comparison of homologous tissues (hepatoma--liver) has evidenced that hepatoma mitochondria are "lighter" even than the "light" fraction of normal ones, that seems to evidence the disturbances in the biogenesis of these organelles. The results obtained are in a good agreement with the data reported by S. A. Neifakh on alterations in the structure of tumor mitochondrial membranes.
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PMID:[Differences in the buoyant density of mitochondria from hepatoma, Krebs ascitic tumor II and normal liver]. 17 12

In acute CCL4 intoxication of rats significantly increased activities of hepatic low-Km hexokinases, glucose-6-phosphate dehydrogenase, phosphofructokinase, aldolase A and pyruvate kinase M2 with concurrently decreased activities of glucokinase, glucose-6-phosphatase, fructose-1,6-diphosphatase, aldolase B and pyruvate kinase L were observed. The resulting enzyme pattern was apparently different from that in dietary induction. Principal component analysis revealed that the degree of enzyme deviation in the injured liver was much greater than that in the regenerating liver after partial hepatectomy and was closer to that in fetal liver or hepatoma tissue.
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PMID:Undifferentiated patterns of key carbohydrate-metabolizing enzymes in injured livers. I. Acute carbon-tetrachloride intoxication of rat. 17 79

For the biochemical characterization of a new transplantable hepatoma derived from the MC-29 virus-induced liver tumor, the macromolecular content and the inducibility of glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, and aryl hydrocarbon hydroxylase were compared in chicken liver and in this hepatoma. The alteration of the nucleocytoplasmic ratio was deduced from measurements of DNA, RNA, protein, and phospholipid contents of the whole cell homogenate and cell fractions. The increased nuclear and decreased cytoplasmic content of macromolecules suggests a dominancy of the nuclei in the tumor cells. Glucose-6-phosphatase and aryl hydrocarbon hydroxylase activities were lower by 60 and 80%, respectively, in the highly proliferating hepatoma than in the liver. In contrast, glucose-6-phosphate dehydrogenase activity increased in the hepatoma. However, enzyme inducers, such as methylcholanthrene, hydrocortisone, and insulin, were able to enhance the activity of these enzymes in the liver but had no stimulating effect on the hepatoma.
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PMID:Biochemistry and enzyme induction in MC-29 virus-induced transplantable avian hepatoma. 17 98

In older patients with glucose-6-phosphatase deficiency adenomatous nodules develop within the liver parenchyma. Investigation of eight such patients, age 3 to 28 years, using radioisotopic scans, has demonstrated areas of depressed isotope uptake in the liver in all except the one preteenaged child. Three patients were further studied with hepatic angiograms and liver biopsy specimens. A diffuse nodularity, more widespread than apparent on isotopic scans, was demonstrated on angiograms. Although initial histologic study in each case showed adenomatous tissue without evidence of neoplasm, the development of hepatocellular carcinoma in one of our patients and in others from the literature suggests that the nodules may be premalignant.
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PMID:Hepatic adenomata with type 1 glycogen storage disease. 18 26

The standard lead precipitation method was used for ultracytochemical localization of glucose-6-phosphatase (G-6-Pase) in the in vivo and in vitro forms of the Chang rat hepatoma and in the normal adult rat liver. Reaction product was visualized as very fine particulate within the cisternae of the nuclear envelope and endoplasmic reticulum. Cytochemically, the amount of the G-6-Pase reaction product in both forms of the tumor cells was obviously less than that in the normal hepatocytes. Apparently, the enzyme was not completely deleted from the hepatoma cells. The results supported some biochemical data of certain other hepatomas. The successful ultracytochemical localization of G-6-Pase in cultured hepatoma cells has not been reported previously.
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PMID:Ultracytochemical localization of glucose-6-phosphatase in Chang rat hepatoma in vivo and in vitro. 19 99

A comparative study of glucose-6-phosphatase, alcaline RNase, ATPase, inosine diphosphatase and 5'-nucleotidase activities in isolated rat liver and hepatoma-27 nuclei and nuclear envelopes was performed. The tumor nuclear membranes were shown to be free from G-6-Pase activity in contrast to the liver nuclear membranes. The nuclear RNase activity was strongly inhibited in the hepatoma and could be unmasked in the presence of 3-10(-4) M pCMB. Hepatoma nuclear and nuclear envelopes ATP-ase activity was found to be moderately decreased as compared to those of the normal tissue. The values of inosine diphosphatase activity in hepatoma were similar to those in liver. The role of the nuclear envelope in nuclear-cytoplasmic interactions as well as nuclear location of G-6-Pase are discussed.
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PMID:[Various enzymes of isolated nuclear membranes and cell nuclei of the liver and hepatoma 27 of rats]. 19 29

Activities of the key enzymes of glycolysis and gluconeogenesis were studied in soluble fraction of primary hepatoma, induced by diethyl nitrosamine (DENA) in rats and mice of C3HA strain. Histological structure of the tumors studied showed that they belonged mainly to highly differentiated hepatocellular adenomas. Liver tissue of the animals which were not treated with DENA, was used as a control. The hexokinase activity was increased about 2-fold in the rat hepatomas and 3-fold--in the mice hepatomas. In primary hepatomas the glucokinase activity was unaltered or slightly decreased; the fructokinase activity was distinctly decreased (in several cases down to zero). The activity of key enzymes of gluconeogenesis--glucose-6-phosphatase and fructose-1,6-diphosphatase--was distinctly decreased, especially the activity of the former enzyme, which constituted in hepatomas about 1/6 of the activity found in liver tissue.
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PMID:[Activity of enzymes of glycolysis and gluconeogenesis in primary hepatomas induced by diethylnitrosamine]. 20 3

The activities of pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G6Pase), and glycogen synthetase (GS) were determined in the cancerous and in the apparently uninvolved (host) regions of livers from primary hepatoma patients as well as in normal adult human livers and human fetal livers. The activities of these enzymes were also assayed in a fairly fast-growing, 3'-methyl-4-dimethylaminoazobenzene-induced transplantable rat hepatoma and in hepatoma cell lines derived from both rat and human tumors. In the human hepatoma, as in the rat hepatoma, the activities of PC, PEPCK, and G6Pase were considerably reduced, compared to those in the host liver. The activities of both the a (glucose 6-phosphate-independent) and b (glucose 6-phosphate-dependent) forms of GS were also lower in human and rat hepatomas than in the respective host livers. Activities of PC, PEPCK, and G6Pase in the human hepatomas were often comparable with those of fetal livers. In rat and human hepatoma cells, the activities of PC, PEPCK, and G6Pase were similar to or lower than the activities in the respective hepatomas; the activities of GS a were also similar to those in the hepatoma, whereas the activities of GS b were somewhat higher.
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PMID:Activities of key gluconeogenic enzymes and glycogen synthase in rat and human livers, hepatomas, and hepatoma cell cultures. 20 62

In order to study the lipid dependence of glucose-6-phosphatase the lipid composition of microsomes from rat liver and hepatoma was modified using lipid exchange proteins. It was shown that the enzyme activity depends on the presence of phosphatidyl ethanolamine and phosphatidyl serine, but is unaffected by the enrichment of the microsomes with phosphatidyl choline. On the basis of the data obtained it was assumed that the aminophospholipids are required for the functioning of the protein carrier; however, they do not affect the activity of the catalytic component of the glucose-6-phosphatase system on the inner surface of the microsomal membrane.
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PMID:[Study of lipid dependence of glucose-6-phosphatase from rat liver and hepatoma using lipid exchange proteins]. 22 70


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