LSCs may also avoid eradication by modulating host immune surveillance in TME, and cytotoxic T lymphocytes (CTLs) fail to induce an appropriate immune response against CML cells through CTLs exhaustion due to the interaction of the PD-1 receptor expressed on CTLs with the inhibitory ligand PD-L1 expressed on CML cells (156). This evidence concerns the gene CD274 and chronic myelogenous leukemia, BCR-ABL1 positive.