title: Inhibitory effect of meloxicam, a cyclooxygenase-2 inhibitor, on N-nitrosobis (2-oxopropyl) amine induced biliary carcinogenesis in Syrian hamsters.
abstract: Pancreaticobiliary maljunction (PBM) is a high risk factor in biliary tract carcinoma. The chemopreventive action of a cyclooxygenase (COX)-2 inhibitor (meloxicam) on N-nitrosobis (2-oxopropyl) amine (BOP)-induced gallbladder cancer in hamster PBM models was investigated. In 7-week-old female Syrian golden hamsters, the extrahepatic bile duct at the distal end of the common duct was ligated and cholecystoduodenostomy was performed (group I). In group II, the same surgery was performed and from week 4 after surgery, 10 mg/kg of BOP was injected subcutaneously once a week with a 1-week interval. In group III, in addition to the measures employed in group II, 5 mg/kg/day of meloxicam was administered once a day, every weekday. Pathological findings in the gallbladder in week 20 after surgery were as follows. In group I, proper epithelium (PE) was predominant and there was no cancer. In group II, PE was predominant, but there was also hyperplasia and atypical epithelium (AE) recognized in 8 of 11 cases (72.7%); the area of AE was more extensive than that in group I. Carcinoma in situ (CIS) was recognized in 4 of 11 cases (36.4%) in group II. Group III showed the same pathological findings as group I. However, compared with group II, the incidence of AE decreased to 27.3% and no cancerous lesion was observed. In week 20 after surgery, the proliferative cell nuclear antigen labeling index in group III was statistically significantly lower than in group II (P = 0.045). No statistically significant differences were noted among the groups in terms of apoptosis labeling index in week 20 after surgery. In conclusion, it was confirmed that meloxicam suppresses carcinogenesis in hamster PBM models and its mechanism may be based on the suppression of cell growth.
authors.affiliation: Third Department of Surgery, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan. akibobo@hotmail.com
authors.forename: Akihiko
authors.initials: A
authors.lastname: Tsuchida
authors.forename: Takao
authors.initials: T
authors.lastname: Itoi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Kasuya
authors.forename: Mitsufumi
authors.initials: M
authors.lastname: Endo
authors.forename: Kenji
authors.initials: K
authors.lastname: Katsumata
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Aoki
authors.forename: Minako
authors.initials: M
authors.lastname: Suzuki
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Aoki
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002273:Carcinogens / Q000633:toxicity*; D002278:Carcinoma in Situ / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control; D049109:Cell Proliferation / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D006224:Cricetinae; D051546:Cyclooxygenase 2 / Q000737:chemistry; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D004195:Disease Models, Animal; D004848:Epithelium / Q000187:drug effects / Q000473:pathology; D005260:Female; D005704:Gallbladder / Q000187:drug effects / Q000473:pathology; D005706:Gallbladder Neoplasms / Q000139:chemically induced* / Q000473:pathology / Q000517:prevention & control*; D006965:Hyperplasia / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control; D000077239:Meloxicam; D008647:Mesocricetus; D009602:Nitrosamines / Q000633:toxicity*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013843:Thiazines / Q000494:pharmacology*; D013844:Thiazoles / Q000494:pharmacology*
chemical_list: D002273:Carcinogens; D016861:Cyclooxygenase Inhibitors; D009602:Nitrosamines; D018809:Proliferating Cell Nuclear Antigen; D013843:Thiazines; D013844:Thiazoles; C013622:nitrosobis(2-oxopropyl)amine; D051546:Cyclooxygenase 2; D000077239:Meloxicam