Comparison of threein vitroassays for carcinogen#x2010;induced DNA damage

摘要

DNA damage induced by five ultimate carcinogens and five procarcinogens was evaluated by three methods: (1) DNA strand breaks in Crandall feline kidney (CRFK) cells measured by alkaline sucrose gradient centrifugation; (2) unscheduled DNA synthesis (UDS) in CRFK, Syrian hamster embryo (SHF), and rat hepatocyte cultures measured by liquid scintillation counting; and (3) UDS in CRFK, SHE, and rat hepatocyte cultures measured by autoradiography. DNA strand breaks were observed with three procarcinogens and four ultimate carcinogens. Only two procarcinogens and two ultimate carcinogens could be identified by liquid scintillation counting. A positive autoradiographic response for UDS was observed in CRFK cells with four of five ultimate carcinogens and one procarcinogen. SHE cells showed a positive autoradiographic response for UDS with all ultimate carcinogens and three procarcinogens. The autoradiographic system with primary rat hepatocyte cultures was the only one in which a positive response for DNA damage was elicited for all 10 carcinogens.