Effects of methoxychlor on skin tumor development.
Organochlorine pesticides increase the incidence of liver cancer through a multistage process involving tumor promotion. Mirex, an organochlorine pesticide has been shown to be a tumor promoter in mouse skin. In the present study, the effects of methoxychlor, a commonly used organochlorine pesticide, on the development of papillomas in 7,12-dimethylbenz[a]anthracene (DMBA)-initiated mouse skin and induction of mouse epidermal ornithine decarboxylase (ODC) activity were investigated and compared with 12-O-tetradecanoylphorbol-13-acetate (TPA), a well-known tumor promoter. Methoxychlor neither caused tumor development nor induced epidermal ODC activity. However, TPA resulted in 100% tumor incidence and 8.8 tumors per mouse after 20 weeks of promotion, and induced epidermal ODC activity.
Dwivedi
C
C
College of Pharmacy, South Dakota State University, Brookings 57007.
Tabbert
J
J
D015127:9,10-Dimethyl-1,2-benzanthracene / Q000008:administration & dosage / Q000633:toxicity; D000818:Animals; D004195:Disease Models, Animal; D004790:Enzyme Induction / Q000187:drug effects; D004817:Epidermis / Q000187:drug effects / Q000201:enzymology; D005260:Female; D008731:Methoxychlor / Q000008:administration & dosage / Q000633:toxicity*; D051379:Mice; D009955:Ornithine Decarboxylase / Q000096:biosynthesis; D010212:Papilloma / Q000139:chemically induced*; D012878:Skin Neoplasms / Q000139:chemically induced*; D013755:Tetradecanoylphorbol Acetate / Q000008:administration & dosage / Q000633:toxicity
D015127:9,10-Dimethyl-1,2-benzanthracene; D009955:Ornithine Decarboxylase; D013755:Tetradecanoylphorbol Acetate; D008731:Methoxychlor