High expression of cytochrome P450 2a-5 (coumarin 7-hydroxylase) in mouse hepatomas
- 1 January 1993
- journal article
- research article
- Published by Wiley in Molecular Carcinogenesis
- Vol. 7 (4) , 276-280
- https://doi.org/10.1002/mc.2940070411
Abstract
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.Keywords
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