NOS2 and neoplasm: However, the suppression of carcinogenesis has also been linked to inhibition of pro-inflammatory mediators such as nuclear factor kappa B (NF-κB) and Stat325, to the induction of tumor suppressor pathways regulated by the prostaglandin degrading enzyme 15-hydroxyprostaglandin dehydrogenase (15-PGDH) and by TGF-β26, and through potent transcriptional repression of inducible nitric oxide synthase (iNOS)27.