The results of immunohistochemistry and semiquantitative assessment show that COX-2 expression increases as the nasopharyngeal epithelium develops from normal to dysplastic and then into NPC, indicating that COX-2 promotes the development of NPC.26, 27 This suggests that PTGS2 might be associated with NPC. Here, PTGS2 is linked to nasopharyngeal carcinoma.