PTGS2 and breast cancer: Frequently, overexpression of cyclooxygenase-2 (COX-2) had been found in several types of tumor, including breast cancer (Regulski et al., 2015) and glioblastoma (Onguru et al., 2008), and implicated in inflammation and tumorigenesis, indicating that inhibition of COX-2 may exhibit a potential anticancer effect.