VAV1 and acute promyelocytic leukemia: Our data allow to conclude that PU.1 may regulate the expression of miR‐29b in both APL and non‐APL cells and to establish that the contribution of the 2 miRNA precursors is cell‐related and almost completely dependent on Vav1 that plays peculiar roles in APL‐ and non‐APL–derived cell lines.