PTEN and acute leukemia: Here, we demonstrated that, 1) IGFBP2 is highly expressed by certain types of acute leukemia cells, 2) IGFBP2 is a cell-autonomous factor that promotes the development of acute leukemia, 3) IGFBP2 supports both survival and migration of leukemia cells, and 4) the stimulating effect of IGFBP2 on acute leukemia cells depends on PTEN signaling.