PTGS2 and glioma: Moreover, the production of a significant amount of ROS induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) can activate the MAPK pathway and cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) pathways, subsequently enhancing the in vitro migration and invasion capability of glioma cells (24).