This constitutive expression was in line with that observed in tumor lines (Uyttenhove et al., 2003) and was subsequently found to be triggered by an autocrine loop of prostaglandin E2 secretion produced by COX2 (Cyclooxygenase 2) expressed as a result of oncogenic signaling (Hennequart et al., 2017). Here, PTGS2 is linked to neoplasm.