Inhibitory effect of inducible nitric oxide synthase inhibitors on DMBA-induced hamster buccal-pouch squamous-cell carcinogenesis.
We investigated the effects of two NOS inhibitors (AG and l-NAME) on DMBA-induced hamster buccal-pouch carcinogenesis. Six hundred Syrian golden hamsters were split into two divisions (I and II); divisions split into three groups (experimental groups A and B, control group C); and each group into subgroups of 20 (A1-A6, B1-B6 and C1-C3). The pouches of animals in groups A1-A3 were painted first with AG of differing concentrations (10, 20, and 30 micromol/ml) and then 30 min later with DMBA (0.5%), thrice weekly for 9 weeks. Subgroups A4-A6 only received AG treatment. Groups B1 to B6 were similarly treated with l-NAME. Animals in division II were treated in the same manner for 13 weeks. Post-mortem analysis revealed that both inhibitors can suppress the development of epithelial dysplasias and squamous-cell carcinomas. An associated increase in the numbers of epithelial hyperplasias was paralleled by a decrease in iNOS protein expression. This animal model can be employed to evaluate the potential use of iNOS inhibitors as novel therapeutic tools for oral squamous-cell carcinogenesis.
Chen
Yuk-Kwan
YK
Oral Pathology Department, School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan.
Huse
Shue-Sang
SS
Lin
Li-Min
LM
D015127:9,10-Dimethyl-1,2-benzanthracene / Q000494:pharmacology*; D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced / Q000201:enzymology* / Q000473:pathology / Q000517:prevention & control*; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D006224:Cricetinae; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006146:Guanidines / Q000494:pharmacology*; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology*; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000378:metabolism
D004791:Enzyme Inhibitors; D006146:Guanidines; D015127:9,10-Dimethyl-1,2-benzanthracene; D052247:Nitric Oxide Synthase Type II; C004479:pimagedine; D019331:NG-Nitroarginine Methyl Ester