No evidence that polymorphisms in CYP2C8, CYP2C9, UGT1A6, PPARδ and PPARγ act as modifiers of the protective effect of regular NSAID use on the risk of colorectal carcinoma

Objectives Regular continuous non-steroidal anti-inflammatory drug (NSAID) use has been associated with a reduction in risk of colorectal cancer. Our objective was to investigate whether or not a number of the polymorphic genes involved in the metabolism of NSAIDs, including cytochrome P450s (CYPs), act as modifiers of this protective effect. Methods As part of a multi-centre case-control study, 478 colorectal cancer patients and 733 controls (433 matched case-control pairs) answered questions on NSAID use. These individuals were then genotyped for common polymorphisms in P450 CYP2C8, P450 CYP2C9, UDP-glucuronosyl transferase (UGT)1A6 and peroxisome proliferator-activated receptor isoforms delta and gamma (PPAR delta and PPAR gamma). Results and conclusion Our study confirmed the reduction in risk of colorectal cancer with regular NSAID use (odds ratio (OR)=0.73, 95% confidence interval (Cl) (0.56, 0.95)) but showed that none of the polymorphic genes studied appeared to modify the protective effect of regular NSAID use.