PTGS2 and cancer: Many epidemiological studies have investigated the effects of nonspecified or combined (COX2 and traditional) NSAIDs on cancer risk (Garcia Rodriguez and Huerto-Alvarez, 2001; Sørensen et al, 2003; Jacobs et al, 2005; Hernández-Díaz and García Rodríguez, 2006; Bardia et al, 2007; Gallicchio et al, 2007).