CD274 and T-cell non-Hodgkin lymphoma: The inhibitory receptor programed cell death protein 1 (PD-1) and its ligand, programmed death-ligand 1 (PD-L1), are widely expressed by malignant T-cell lymphomas and surrounding nonmalignant T cells (81, 82), though PD-1 may function as a haploinsufficient tumor suppressor, and therefore checkpoint inhibitors have the potential to accelerate existing T-cell lymphomas (83).