2-(1,8-Naphthyridin-2-yl)phenol (2-NP) is an enhancer of STAT1 activity.{56126} It enhances IFN-y-induced STAT1-dependent signaling, but not IFN-y-induced STAT3-dependent signaling or TNF-a-induced NF-kB-dependent signaling in cell-based reporter assays when used at a concentration of 45 µM. 2-NP (45 µM) increases IFN-y-induced expression of the STAT1 target gene IRF3 and STAT1 phosphorylation in NIH3T3 cells. It increases growth inhibition of MCF-7 and 2fTGH cancer cells induced by IFN-y at the same concentration.