PTGS2 and neoplasm: Since the transcriptions of ARG1, IDO2, inducible nitric oxide synthetase (NOS2), Ptgs2, Ptger4, and NOX1 are all regulated by the coactivators CEBPA/B, which also function in this capacity with PPARδ, this suggests a mechanism whereby PPARδ may control adaptive immunity metabolically within the tumor microenvironment.