Hybrid clones of rat liver and hamster ovary cells as targets for carcinogen screening.
Many short-term carcinogen-screening assays use transformed cells which require exogenous metabolizing systems to activate carcinogens. We have sought untransformed target cell-lines with a high mitotic index and the intrinsic ability to metabolize carcinogens. Hybrid cell clones were established by fusing an untransformed rat liver cell-line (with a normal diploid karyotype, epithelial morphology and carcinogen-metabolizing capacity) and a Chinese hamster ovary cell-line (with a high mitotic index, ability to grow in soft agar, a characteristic of transformed cells, and which cannot metabolize most carcinogens). A number of such clones were characterized with respect to their morphology, karyology, growth properties and the ability to metabolize 7,12-dimethylbenz[a]anthracene. Selected hybrid clones were found to respond to several types of carcinogen, using the induction of sister chromatid exchange as the criterion. A significant increase in the induction was observed in cloned hybrid cell-lines compared with the hamster ovary cell line. Moreover, the same hybrid clones can be used repeatedly without an exogeneous activating system, which makes this test system very practical.
D000818:Animals; D002273:Carcinogens / Q000378:metabolism / Q000494:pharmacology*; D002875:Chromosomes / Q000187:drug effects; D002999:Clone Cells; D004353:Drug Evaluation, Preclinical / Q000379:methods; D005260:Female; D006822:Hybrid Cells / Q000187:drug effects*; D008099:Liver / Q000166:cytology; D008297:Male; D010053:Ovary / Q000166:cytology; D051381:Rats; D012854:Sister Chromatid Exchange / Q000187:drug effects
D002273:Carcinogens