PTGS2 and neoplasm: COX-2/PGE2 signaling has been described in multiple models of cancer, including oral, breast, prostate, and colorectal, with documented roles in tumor initiation, invasion, immune evasion, cell survival, metastasis, vascular remodeling, cancer stem cells, and drug resistance; for further review, see Hashemi Goradel et al.[46] and Stasinopoulos et al. [48].