The ligands for PD-1, programmed cell death ligand 1 (PD-L1) and programmed cell death ligand 2‚ as well as the ligands for CTLA-4, B7-1 (CD80), and B7-2 (CD86), are upregulated in both solid tumors and hematological malignancies. This evidence concerns the gene CD80 and hematologic disorder.