CD274 and melanoma: Antibodies targeting PD-L1 (MPDL3280A, MEDI4736 and BMS-936559) have demonstrated anti-tumor activity in diverse tumor types, including renal cell carcinoma (RCC) [14], advanced melanoma [6], non-small cell lung cancer (NSCLC) [6, 14, 15], and bladder cancer [13] among others [2, 16].