While leukemia did not affect the number of mesenchymal stem/stromal cells (MSCs) [40], PDGFRα+Sca-1+ (PαS) mesenchymal cells [41], CXCL-12 abundant reticular cells [42] and vimentin+ fibroblasts [43], we observed significantly lower numbers of endothelial and osteoblastic cells (Fig. 2a, b; Supplementary Figure 3). This evidence concerns the gene CXCL12 and leukemia.