Transformation of hamster embryo cells by neutral sterols and bile acids.

Toxicity and cell transformation of Syrian hamster embryo cells in culture by certain neutral sterols and bile acids show interesting trends related to their structures: cholesterol-alpha-epoxide and cholestan-3 beta, 5 alpha, 6 beta-triol were more toxic and induced transformation to these cells, whereas their metabolic precursor, cholesterol, was inactive. The secondary bile acids, lithocholic and deoxycholic acids, were more toxic than their primary bile acid precursors, cholic and chenodeoxycholic acids and transformed the cells. These data suggest that mammalian cell transformation is a useful short-term assay to measure the potential toxicity and carcinogenicity of steroid derivatives.