CD274 and acute myeloid leukemia: Recently, it was observed that bone marrow-infiltrating CD8+ T cells from acute myeloid leukemia (AML) patients demonstrated downregulated expression of immune checkpoint (IC) receptors including PD-1 which could contribute to upregulation of immune checkpoint ligands such as PD-L1 due to poor PD-1/PD-L1 interaction (117).