title: Chemopreventative effect of an inducible nitric oxide synthase inhibitor, ONO-1714, on inflammation-associated biliary carcinogenesis in hamsters.
abstract: The present study was designed to investigate whether an inducible nitric oxide synthase (iNOS)-specific inhibitor, ONO-1714 [(1S, 5S, 6R, 7R)-7-chloro-3-imino-5-methyl-2-azabicyclo[4.1.0] heptane], could prevent inflammation-associated biliary carcinogenesis in bilioenterostomized hamsters. Syrian golden hamsters underwent choledochojejunostomy and then received subcutaneous injections of the chemical carcinogen N-nitrosobis(2-oxopropyl)amine every 2 weeks at a dose of 10 mg/kg body wt, starting 4 weeks after surgery and continuing for 18 weeks. The hamsters were divided into two groups according to their oral intake of either a standard pelleted diet containing ONO-1714 at 100 p.p.m. for 18 weeks (ONO group, n = 15) or an ordinary diet alone (control group, n = 15). The animals were killed 22 weeks after surgery, and the development of biliary tumors was examined histologically. The presence and degree of cholangitis, cell kinetic status of the biliary epithelium and iNOS expression were evaluated. Intrahepatic biliary adenomas developed in all control animals, whereas they developed in only seven (47%) hamsters treated with ONO-1714 (P < 0.05). Intrahepatic biliary carcinomas were present in 13 (87%) hamsters in the control group and in only 6 (40%) hamsters in the ONO groups (P < 0.05). Histological and immunohistochemical examinations demonstrated a significant decrease in the degree of cholangitis, biliary epithelial cell kinetics and the expression of iNOS in the biliary epithelium in the ONO group in comparison with the control (P < 0.05). These results indicate that ONO-1714 represses N-nitrosobis(2-oxopropyl)amine-induced biliary carcinogenesis in bilioenterostomized hamsters and inhibits iNOS expression in the biliary epithelium. ONO-1714 may therefore be a promising agent for the prevention of biliary carcinoma in various inflammation-associated biliary disorders.
authors.affiliation: Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto, Nagasaki, Japan. tamishima-gi@umin.ac.jp
authors.forename: Takehiro
authors.initials: T
authors.lastname: Mishima
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Tajima
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Kuroki
authors.forename: Taiichiro
authors.initials: T
authors.lastname: Kosaka
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Adachi
authors.forename: Amane
authors.initials: A
authors.lastname: Kitasato
authors.forename: Noritsugu
authors.initials: N
authors.lastname: Tsuneoka
authors.forename: Tomoo
authors.initials: T
authors.lastname: Kitajima
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanematsu
mesh_terms: D000578:Amidines / Q000494:pharmacology*; D000713:Anastomosis, Roux-en-Y; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001652:Bile Ducts / Q000187:drug effects / Q000473:pathology; D002273:Carcinogens / Q000494:pharmacology; D002763:Cholecystectomy / Q000379:methods; D006224:Cricetinae; D005260:Female; D005706:Gallbladder Neoplasms / Q000517:prevention & control*; D006574:Heterocyclic Compounds, 2-Ring / Q000494:pharmacology; D007249:Inflammation / Q000150:complications / Q000503:physiopathology*; D007582:Jejunostomy; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008647:Mesocricetus
chemical_list: C407360:7-chloro-3-imino-5-methyl-2-azabicyclo(4.1.0)heptane; D000578:Amidines; D000893:Anti-Inflammatory Agents; D002273:Carcinogens; D006574:Heterocyclic Compounds, 2-Ring