PTGS2 and carcinoma: This hypothesis is tested in a Cox-2−/− mouse tongue cancer model that mimics pharmacologic blockade of COX-2 by firstly examining transcriptome profiles of forestomach mucosa from Cox-2−/− and wild-type mice on a ZD vs. ZS diet, and secondly investigating the roles of identified markers in mouse forestomach/tongue preneoplasia and carcinomas.