title: Immunohistochemical expression of inducible nitric oxide synthase in DMBA-induced hamster buccal pouch carcinogenesis.
abstract: Nitric oxide (NO) plays a key role in the processes of inflammation and carcinogenesis. Three isoforms of NO synthase have been identified: endothelial nitric oxide synthase (NOS), neuronal NOS, and inducible NOS (iNOS). The purpose of this study was to investigate the characteristics of iNOS in 7, 12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis. Thirty outbred young (6-week-old) male Syrian golden hamsters were randomly divided into three groups: DMBA (0.5%) painted group (n=10); mineral oil-treated group (n=10); and non-treated group (n=10). The average number of iNOS positive foci per section in the DMBA-treated group was approximately 12.2+/-4.7. Both cytoplasmic and nuclear stainings were observed in the DMBA-treated pouch keratinocytes. No iNOS activity could be detected in the untreated or mineral oil-treated pouches. In conclusion, this study has demonstrated that iNOS is expressed in DMBA-induced hamster pouch carcinomas. This finding suggests that iNOS expression may be associated with the development of chemically induced oral carcinomas.
authors.affiliation: Oral Pathology Department, School of Dentistry, Kaohsiung Medical College, 100 Shih-Chuan 1st Road, Kaohsiung, Taiwan, ROC.
authors.forename: Y K
authors.initials: YK
authors.lastname: Chen
authors.forename: L M
authors.initials: LM
authors.lastname: Lin
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D002273:Carcinogens; D006224:Cricetinae; D007150:Immunohistochemistry; D008297:Male; D008647:Mesocricetus; D009062:Mouth Neoplasms / Q000139:chemically induced / Q000201:enzymology*; D009374:Neoplasms, Experimental; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II
chemical_list: D002273:Carcinogens; D015127:9,10-Dimethyl-1,2-benzanthracene; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II