Enzyme patterns in human hepatocellular carcinoma.
Characteristic enzyme alterations have been demonstrated during the stages of experimental hepatocarcinogenesis in rats. The activity of gamma-glutamyl transpeptidase (GGTPase) in hyperplastic and neoplastic hepatocytes is usually increased, whereas that of canalicular adenosine triphosphatase (ATPase) and of glucose-6-phosphatase (G6Pase) is more variable. The activities of these marker enzymes were studied by histochemical techniques in 10 human hepatocellular carcinomas (HCCs), 1 liver cell adenoma, and 1 cholangiocarcinoma of liver. In 9 cases, the nontumorous liver was also examined. All HCCs, but not the liver cell adenoma, displayed enzyme patterns that differed from normal. GGTPase activity was markedly increased in 8 HCCs, whereas the activities of G6Pase and ATPase were lost in 6 and 8 HCCs, respectively. These enzyme alterations occurred as 5 of 7 possible combinations, resulting in significant heterogeneity of enzyme phenotypes, similar to that in experimental hepatocarcinogenesis.
D002759:Adenoma, Bile Duct / Q000201:enzymology*; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000201:enzymology*; D005260:Female; D005952:Glucose-6-Phosphatase / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms / Q000201:enzymology*; D008297:Male; D008875:Middle Aged
D005952:Glucose-6-Phosphatase; D000251:Adenosine Triphosphatases