Because the endosteal endothelium has been shown to locate next to and sustain osteoblasts (Kusumbe et al., 2014), we expanded our analysis of the endosteal microenvironment to include a focused investigation of osteoblastic cells (CFP+ or GFP+ cells in Col2.3-CFP/GFP reporter mice, respectively) during AML growth. This evidence concerns the gene CFP and acute myeloid leukemia.