title: Effects of nobiletin on PhIP-induced prostate and colon carcinogenesis in F344 rats.
abstract: The current study was designed to investigate the effects of nobiletin (5,6,7,8,3',4'-hexamethoxy flavone) on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced prostate and colon carcinogenesis. PhIP was administered to 6-wk-old F344 male rats intragastrically (100 mg/kg) twice a wk for 10 wk. The animals were given 0.05% nobiletin or the basal diet for 50 wk. At the end of the experiment, serum testosterone, estrogen, and leptin did not differ between the 2 groups. The body weights of nobiletin-treated rats were significantly higher than controls (P<0.05), and feeding of nobiletin significantly reduced the relative prostate (P<0.05) and testes (P<0.05) weights as well as the Ki67 labeling index in the normal epithelium in the ventral prostate (P<0.01). The incidence and multiplicity of adenocarcinomas in nobiletin-treated ventral prostate were 50% and 36%, respectively, of controls, but the differences were not statistically significant. However, nobiletin did significantly reduce the total number of colonic aberrant crypt foci (ACF) compared to the control value (P<0.05). Nobiletin, therefore, may have potential for chemoprevention of early changes associated with carcinogenesis in both the prostate and colon.
authors.affiliation: Department of Experimental Pathology and Tumor Biology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Ming Xi
authors.initials: MX
authors.lastname: Tang
authors.forename: Kumiko
authors.initials: K
authors.lastname: Ogawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Asamoto
authors.forename: Teera
authors.initials: T
authors.lastname: Chewonarin
authors.forename: Shugo
authors.initials: S
authors.lastname: Suzuki
authors.forename: Takuji
authors.initials: T
authors.lastname: Tanaka
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Shirai
mesh_terms: D058739:Aberrant Crypt Foci; D000230:Adenocarcinoma / Q000139:chemically induced; D000818:Animals; D002273:Carcinogens / Q000633:toxicity; D018890:Chemoprevention; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000188:drug therapy*; D047309:Flavones / Q000494:pharmacology*; D007093:Imidazoles / Q000633:toxicity*; D008297:Male; D009929:Organ Size; D011467:Prostate / Q000473:pathology; D011471:Prostatic Neoplasms / Q000139:chemically induced / Q000188:drug therapy*; D051381:Rats; D011916:Rats, Inbred F344; D013737:Testis / Q000473:pathology
chemical_list: D002273:Carcinogens; D047309:Flavones; D007093:Imidazoles; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine; C008661:nobiletin