The Binding of Polycyclic Aromatic Hydrocarbons to the DNA, RNA, and Proteins of Transformable Cells in Culture1

The binding of several labeled carcinogenic hydrocarbons to macromolecular constituents of various cells involved in systems for chemical carcinogenesis in vitro was studied. The hydrocarbons were firmly bound to the DNA, RNA, and proteins of cultured embryonic cells from C3H mice and hamsters and of various cells derived from C3H mouse prostates. The extent of binding in the embryonic cells was very similar to that previously found with mouse skin in vivo. Chemically and spontaneously transformed cells bound 5 to 10 times less hydrocarbon than did the parental nontransformed prostate cells, although less malignant variants obtained from highly malignant clones bound the hydrocarbons to two-thirds the extent of the nontransformed cells. In a series of 5 hydrocarbons, benzo[a]pyrene was bound to proteins to the highest extent, and 7,12-dimethylbenz[a] anthracene was