Additionally, B-ALL cells, but not normal CD34+ precursor cells, expressed CXCR3 and CXCR7, the receptors for CXCL10, CXCL11, and CXCL12, suggesting their advantage for selective niche colonization (Figures 7D, E and Supplementary Figure S7A). This evidence concerns the gene CXCL12 and acute lymphoblastic leukemia.