Carcinogen-induced DNA repair in primary rat liver cell cultures; a possible screen for chemical carcinogens.

Primary rat liver cell cultures were exposed to a direct acting carcinogen, methyl methanesulfonate, and procarcinogens requiring metabolic activation, aflatoxin B1 and B2. DNA damage by these agents was evidenced by the induction of DNA repair, measured as unscheduled DNA synthesis. The sensitivity of these cultures to the potent porcarcinogen aflatoxin B1 indicates that this system may be adapted for screening suspected chemical procarcinogens, and for investigating the relationship between metabolic activation of procarcinogens, DNA damage, DNA repair, and carcinogenicity.