CXCR4 and acute myeloid leukemia: BL8040 is a new-generation CXCR4 inhibitor able to induce the mobilization of AML cells from the protective niche into the circulation and to promote AML differentiation and apoptosis through down-regulation of B-cell lymphoma 2 (BCL-2), myeloid cell leukemia 1 (MCL-1) and cyclin D1 as well as the AKT/ERK signaling pathway [109].