Comparison of hepatocarcinogen-induced gene expression profiles in conventional primary rat hepatocytes with in vivo rat liver

At present, substantial efforts are focused on the development of in vitro assays coupled with ”omics” technologies for the identification of carcinogenic substances as an alternative to the classical 2-year rodent carcinogenicity bioassay. A prerequisite for the eventual regulatory acceptance of such assays, however, is the in vivo relevance of the observed in vitro findings. In the current study, hepatocarcinogen-induced gene expression profiles generated after exposure of conventional cultures of primary rat hepatocytes to three non-genotoxic carcinogens (methapyrilene hydrochloride, piperonyl butoxide and Wy-14643), three genotoxic carcinogens (aflatoxin B1, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and 2-nitrofluorene), and two non-carcinogens (nifedipine and clonidine) are compared with previously obtained in vivo data after oral administration for up to 14 days of the same hepatocarcinogens to rats.