It is also noticeable that E5 not only inhibits leukemia cells from homing to the places where CXCL12 is secreted, but also mobilizes leukemia cells from a pre-established stromal feeder layer by disrupting the adhesion between the leukemia cells and the stromal cells, indicating it is able to drive the cells away from the protective microenvironment. This evidence concerns the gene CXCL12 and leukemia.