CD34 and acute lymphoblastic leukemia: Also, the integrin alpha 6 gene (ITGA6, encoding CD49f), shown in several studies to be upregulated in HSC [68, 69, 70], playing an important role in HSC homing to the BM niche [71], and associating with poor therapy response in ALL [20], was among the top 5 upregulated genes in the CD34‐positive leukemias.