SLC9A1 and precursor B-cell acute lymphoblastic leukemia: Of the six identified targets, CXCR4 mRNA was the most expressed in the 12 B-ALL cell lines available in the CCLE dataset36 (Fig. 6c), whereas CD22 was moderately expressed, and the expression of SLC9A1 (Solute Carrier family 9A1), CCR7 (C-C Motif Chemokine Receptor 7), PPP3CC and CXCR5 (C-X-C Motif Chemokine Receptor 5) was very low or undetectable in these cell lines.