title: Involvement of metallothionein (MT) as a biological protective factor against carcinogenesis induced by benzo[a]pyrene (B[a]P).
abstract: The purpose of this study was to examine whether intracellular metallothionein (MT) protects against benzo[a]pyrene (B[a]P)-induced forestomach and lung carcinogenesis. Ten-week-old male MT-I/II null mice and wild-type mice were orally administered B[a]P at a dose of 100 or 250 mg/kg twice a week for 4 weeks. B[a]P-induced mortality was higher in the MT-I/II null mice than in the wild-type mice. The incidence of tumors in the forestomach and lung was 78.6% and 7.1% in the wild-type mice treated with 100 mg/kg B[a]P, respectively. In the MT-I/II null mice treated with B[a]P, tumor incidence in the forestomach and lung was 100% and 33.3%, respectively. The tumor area in the forestomach and lung in the MT-I/II null mice treated with B[a]P was greater than that of wild-type mice. These results suggest that MT acts as a biological protective factor against carcinogenesis induced by B[a]P.
authors.affiliation: Laboratory of Hygienic Chemistry and Molecular Toxicology, Gifu Pharmaceutical University, Gifu, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Takaishi
authors.forename: Akinori
authors.initials: A
authors.lastname: Shimada
authors.forename: Junko S
authors.initials: JS
authors.lastname: Suzuki
authors.forename: Masahiko
authors.initials: M
authors.lastname: Satoh
authors.forename: Hisamitsu
authors.initials: H
authors.lastname: Nagase
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity*; D005260:Female; D008297:Male; D008668:Metallothionein / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000139:chemically induced* / Q000517:prevention & control
chemical_list: D001564:Benzo(a)pyrene; D008668:Metallothionein