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)

Polysome and ribosome preparations from normal rat liver and from a series of transplantable rat hepatomas of different growth rates were compared. All the hepatomas had a significantly higher percentage of RNA in a polysome preparation than did the normal liver, and the polysome preparations from the tumors, with the exception of the Dunning hepatoma which has a high lipid content, gave a greater yield of RNA and protein per gram of wet tissue than the liver did. Heavier polysomes were considerably less prevalent in the tumors than in the liver, and the tumors contained a larger proportion of monomer and dimer ribosomes than the liver did. Evidence is presented that the increased monomer and dimer ribosome population of the hepatomas studied is not an artifact of preparation, but represents the true intracellular distribution. Ribosomes from normal liver and Morris 5123-D hepatoma were readily dissociated by 20 min' treatment with 1.0 mM EDTA, but ribosomes from the Dunning, Novikoff ascites, and McCoy MDAB hepatomas were little affected by such treatment. With higher concentrations of EDTA, the ribosomes from the Novikoff ascites and McCoy MDAB hepatomas broke down and did not form specific subunits as did ribosomes from liver and the Morris 5123-D hepatoma but rather gave rise to a variety of small degradation products. This behavior is ascribed to a higher RNase content of the Novikoff and McCoy MDAB hepatomas. Dunning hepatoma ribosomes were resistant to 4 mM EDTA.
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PMID:Studies on the function of intracellular ribonucleases. IV. Some observations on the properties of ribosomes and polysomes from rat liver and hepatomas. 428 63

The activity of tyrosine aminotransferase (TAT) decreased biphasically in livers of rats fed 3'-methyl-4-dimethylaminoazobenzene (3'-MDAB). TAT activity decreased to an extremely low level at later stages of hepatocarcinogenesis. The activity of TAT is negatively correlated with alpha-fetoprotein (AFP) levels. The level of TAT enzyme activity in precancerous liver and hepatoma is a reflection of the amount of TAT mRNA. Dexamethasone increased the TAT enzyme activity and TAT mRNA concentration in rat livers during chemical carcinogenesis.
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PMID:Changes in hepatic levels of tyrosine aminotransferase messenger RNA during chemical hepatocarcinogenesis. 620 Feb 5