It is likely that the effect on miR-21 expression relied on a decreased activity of the miR-21 promoter, as shown using CML CD34+ cells transduced with a miR-21 promoter-luciferase lentivirus and treated for 0-24h with either vehicle or 5μM imatinib (Figure 7B). This evidence concerns the gene CD34 and chronic myelogenous leukemia, BCR-ABL1 positive.