title: Lack of involvement of 6-hydroxymethylation in benzo[a]pyrene skin tumor initiation in mice.
abstract: The skin tumor-initiating activities of benzo[a]pyrene (BP), 6-hydroxymethylbenzo[a]pyrene (6-OH-CH2-BP), and 6-methylbenzo[a]pyrene (6-CH3-BP), as well as the effects of 7,8-benzoflavone (7,8-BF), quercetin, and 1-benzylimidazole on their activity, were determined in outbred female CD-1 mice by use of a two stage system of tumorigenesis. The skin tumor-initiating activity of 6-OH-CH2-BP and 6-CH3-BP was 12.5 and 20%, respectively, of the activity of BP, 7,8-BF had little effect on the skin tumor-initiating activity of 6-OH-CH2-BP and 6-CH3-BP. However, a dose-dependent inhibition of BP tumorigenesis by 7,8-BF was noted. Quercetin and 1-benzylimidazole also inhibited BP skin tumor-initiating activity. These findings indicated that direct hydroxymethylation of BP is not an important pathway in the activation of BP in mouse skin tumor initiation.
mesh_terms: D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology; D001580:Benzopyrenes / Q000037:antagonists & inhibitors / Q000378:metabolism*; D001711:Biotransformation; D005260:Female; D005419:Flavonoids / Q000494:pharmacology; D006900:Hydroxylation; D008745:Methylation; D051379:Mice; D009374:Neoplasms, Experimental / Q000139:chemically induced; D010212:Papilloma / Q000139:chemically induced* / Q000378:metabolism; D011794:Quercetin / Q000494:pharmacology; D012878:Skin Neoplasms / Q000139:chemically induced* / Q000378:metabolism
chemical_list: D001562:Benzimidazoles; D001580:Benzopyrenes; D005419:Flavonoids; D011794:Quercetin