CYP2C9 and colorectal cancer: Because CYP2C8 and CYP2C9 show partial overlapping in substrate specificity, particularly related to some NSAIDs such as ibuprofen, celecoxib, diclofenac, or tenoxicam (Tang, 2003; Garcia-Martin et al., 2004; Martinez et al., 2005; Daly et al., 2007; Daily and Aquilante, 2009), it could be speculated that the presence of defect CYP2C8 variant alleles may influence the risk of developing colorectal cancer.