CXCL12 and acute myeloid leukemia: It is shown that human AML stem cells (LSCs) expressed CXCR4, a counter-receptor for CXCL12 that is a potent chemoattractant for HSCs secreted from BM stromal cells, and the blockade of CXCR4–CXCL12 axis abrogated the homing of LSCs and propagation of leukemic cells in a xenotransplantation murine model (79).