CD274 and cancer: Actually, five monoclonal antibodies targeting immune checkpoints have been approved by the U.S. Food and Drug Administration (FDA) for cancer treatment alone or in combination with platinum-based chemotherapy [9], although ongoing study attempts to discover new predictive biomarker of treatment response as well as new strategies to improve immunotherapy efficacy, including the combination of anti-PD-(L)1 and anti-Cytotoxic T Lymphocyte Antigen 4 (CTLA-4) agents [15, 16].