Prostaglandin-endoperoxide synthase 2 (PTGS2, also named as COX-2), which can increase the neoplastic process by promoting proliferation, suppressing apoptosis, and angiogenesis, is an enzyme during conversion of arachidonic acid to prostaglandins [27]. PTGS2 has high expression in every kind of tumor, which was usually induced by cancer promoters, oncogenes, and cytokines [28]. PTGS2 gene associated with the decreasing risk of stroke and MI has been demonstrated [29]. Here, PTGS2 is linked to cancer.