FLT3 and leukemia: The chemotaxis rates (toward CXCL12) of HL-60 cells without FLT3-ITD mutations were 18.14 ± 0.53 (500 ng/ml AMD3100), 16.20 ± 1.08 (1 μg/ml AMD3100), 13.34 ± 0.81 (5 μg/ml AMD3100) and 11.99 ± 0.49 (10 μg/ml AMD3100), indicating a decreasing tendency of leukemia cells to undergo chemotaxis toward CXCL12 with increasing AMD3100 concentrations (P > 0.05).