Rotenone, an anticarcinogen, inhibits cellular proliferation but not peroxisome proliferation in mouse liver.

In previous National Toxicology Program (NTP) studies, rotenone reduced the background incidence of hepatocellular carcinoma in male B6C3F1 mice. In the present studies, rotenone reduced the basal hepatic labeling index of male B6C3F1 mice in a dose-dependent fashion and inhibited hepatocellular proliferation, but not peroxisome proliferation, induced by the peroxisome proliferator Wy-14,643. These results indicate that reduction of hepatic tumors by rotenone may have been due to decreased liver cell replication, that peroxisome proliferation can be induced in the absence of hepatocellular proliferation and suggest rotenone as a potential tool in studies of relationships of cell proliferation, peroxisomal proliferation and hepatocarcinogenesis.