PTGS2 and cancer: Considerable efforts are being made to improve the efficacy of cetuximab against colorectal cancer through rational, mechanism-based development of combinations of cetuximab and other agents, and one combination that has been tested is dual blockade of the EGFR and cyclooxygenase-2 (COX-2) pathways [10], which play complementary roles in the pathogenesis of cancer [11, 12].