CXCL9 and melanoma: In gene expression studies, baseline IFN-γ and CXCL9 were significantly higher in study patients who had a partial or complete response (PR/CR) to treatment versus those with progressive disease, and IFN-γ, IDO1, and CXCL9 were significantly higher in study patients with melanoma who had a PR/CR to treatment versus those with progressive disease.