We observed that more cell death was induced in bulk and CD34+CD38− (Figure 2) than CD34+ proliferating and quiescent CML cells (Figure 4) under the same conditions, probably because the latter had been cultured with MSCs for 5-12 d before therapy to distinguish proliferating and quiescent cells. The gene discussed is CD38; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.