Kobliakov V, Kulikova L, Samoilov D, Lang M A
Institute of Carcinogenesis of Cancer Research Center, Moscow, Russia.
Mol Carcinog. 1993;7(4):276-80. doi: 10.1002/mc.2940070411.
A high level of Cyp2a-5 was found in spontaneous and transplanted mouse hepatomas compared with normal liver. Increased expression of Cyp2a-5 was associated with an increase in coumarin 7-hydroxylation, a marker activity of Cyp2a-5, and the corresponding mRNA, suggesting that regulation of Cyp2a-5 in hepatomas is pretranslational. In contrast, the total P450 content and arylhydrocarbon hydroxylase and amidopyrene demethylase activities decreased. Pyrazole, a strong inducer of Cyp2a-5 in normal mouse livers, also increases this isozyme in hepatomas. A parallel increase in the corresponding mRNA suggests that pyrazole, like the formation of hepatomas, affects the regulation of Cyp2a-5 pretranslationally.
