In a clinical study of melanoma, NSCLC, colorectal cancer, renal-cell cancer, or castration-resistant prostate cancer, pretreatment tumor cell-surface expression of PD-L1 (as determined with immunohistochemistry [IHC]) was correlated with the response to PD-1 blockade, wherein 36% of patients with PD-L1-positive tumors experienced an objective response, while no (0%) patients with PD-L1-negative tumors responded to the treatment [1]. The gene discussed is CD274; the disease is melanoma.