title: Effects of catechol on the induction of tumors in mouse skin by 7,8-dihydroxy-7,8-dihydrobenzo[a]pyrenes.
abstract: Catechol (1,2-dihydroxybenzene) is a major phenolic compound present in the co-carcinogenic fraction of cigarette tar. It has been shown to be a potent co-carcinogen with benzo[a]pyrene (BaP) in mouse skin. In this study we have examined the co-carcinogenic and co-initiating activities of catechol with racemic and enantiomeric 7,8-dihydroxy-7,8-dihydrobenzo[a]pyrenes (BaP-7,8-diols) in mouse skin. Similar to enhancement of BaP carcinogenesis, repeated concurrent applications of catechol and (+/-)-BaP-7,8-diol to mouse skin strongly enhanced (+/-)-BaP-7,8-diol tumor multiplicity and tumor incidence, and decreased latency. Co-application of catechol with the racemic or either of the enantiomers of BaP-7,8-diol in a two-stage initiation--promotion protocol increased the tumor initiating activity of racemic BaP-7,8-diol, similar to that of BaP, by approximately 50%, but had no statistically significant effect on the tumor initiating activity of the (+)- or (-)-enantiomers in mouse skin. Thus, catechol is as potent a co-carcinogen with (+/-)-BaP-7,8-diol as it is with BaP. However, as tested here catechol is a weak co-initiator when applied with (+/-)-BaP-7,8-diol or BaP.
authors.affiliation: American Health Foundation, Naylor Dana Institute, Valhalla, NY 10595.
authors.forename: A A
authors.initials: AA
authors.lastname: Melikian
authors.forename: K G
authors.initials: KG
authors.lastname: Jordan
authors.forename: J
authors.initials: J
authors.lastname: Braley
authors.forename: J
authors.initials: J
authors.lastname: Rigotty
authors.forename: C L
authors.initials: CL
authors.lastname: Meschter
authors.forename: S S
authors.initials: SS
authors.lastname: Hecht
authors.forename: D
authors.initials: D
authors.lastname: Hoffmann
mesh_terms: D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide / Q000633:toxicity*; D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity; D002396:Catechols / Q000494:pharmacology*; D004101:Dihydroxydihydrobenzopyrenes / Q000633:toxicity*; D005260:Female; D051379:Mice; D008815:Mice, Inbred Strains; D012016:Reference Values; D012878:Skin Neoplasms / Q000139:chemically induced* / Q000473:pathology
chemical_list: D002396:Catechols; D004101:Dihydroxydihydrobenzopyrenes; D001564:Benzo(a)pyrene; D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide; C034221:catechol