PTGS2 and colorectal carcinoma: Cyclooxygenase-2 (COX-2) and its major metabolite prostaglandin E2 (PGE2) have also undergone extensive investigation as potential targets of tumor-related angiogenesis, invasion, metastasis, and impairment of apoptosis in a variety of malignancies, including NSCLC and CRC neoplasms.