We suggest that this discrepancy is due to the specific features of the different cell types analyzed: we analyzed in vitro selected chemoresistant, possibly non-leukemic CD34+ cells from CR AML patients, whereas Eisele et al. and Valdez et al. studied myeloid blasts from AML patients [46] or mononuclear cells from AML patients [31], respectively. Here, CD34 is linked to acute myeloid leukemia.