CD274 and cancer: Immune checkpoint molecules such as PD-1 of the coinhibitory signaling pathways are evolved to control the magnitude and duration of T cell responses to limit tissue damage and maintain self-tolerance under physiological and pathological conditions.11 However, tumor cells can hijack these inhibitory pathways to escape host immune surveillance such as by overexpressing the PD-1 ligand PD-L1.11,12 This provides the rationale for clinical application of immune checkpoint inhibitors in cancer immunotherapy.