FLT3 and acute myeloid leukemia: conducted a phase I clinical trial utilizing granulocyte colony stimulating factor (G-CSF which regulates the expression of CXCL12 in the bone marrow), the CXCR4 inhibitor plerixafor and the FLT3 inhibitor sorafenib in relapsed/refractory FLT3-ITD AML patients (NCT00943943).