To validate the predictive value of MAP2K1/2 mutations for the efficacy of anti-CTLA4 therapy in melanoma, data analysis was also performed using a pooled cohort, which was a combination of three metastatic melanoma cohorts treated with ipilimumab (Miao, Samstein, and Snyder) (Table S1). Here, MAP2K1 is linked to metastatic melanoma.