With the advent of therapeutic antibodies reactivating immune checkpoints, HMA treatment has also been shown to upregulate the expression of the inhibitory immune checkpoint receptors programmed death 1 (PD-1) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) in T cells, and their ligands PD-L1 and PD-L2 in tumor cells, respectively. This evidence concerns the gene CTLA4 and neoplasm.