• 1 January 1979
    • journal article
    • research article
    • Vol. 39 (3), 704-710
Abstract
The induction of DNA cross-linking in mammalian cells by various carcinogens was investigated by the method of alkaline elution. A dose-dependent increase in DNA crosslinking was seen following exposure of human fibroblasts to N-acetoxy-2-acetylaminofluorene and following exposure of mouse embryo cells to 7,12-dimethylbenz[a]-anthracene. No cross-link effect was seen following treatment with N-methyl-N''-nitro-N-nitrosoguanidine, benz[a]anthracene, benz[a]anthracene-5,6-dihydroepoxide, or metabolic inhibitors. The cross-linking appeared to be DNA-protein in nature since proteinase treatment removed the effect. DNA single-strand breaks were induced by several of these agents. In the case of N-acetoxy-2-acetylaminofluorene and N-methyl-N''-nitro-N-nitrosoguanidine, .apprx. 70-90% of these breaks were rejoined after an 18 h incubation in fresh medium, whereas repair of the cross-links induced by N-acetoxy-2-acetylaminofluorene was slight at this time.