Setbp1 knockdown inhibits the proliferation of Setbp1-immortalized myeloid progenitors. (A) Left panel, mean and SD of colony formation potential of BM70 cells in the presence of SCF and IL-3 at 48 hours after infection with a Setbp1-specific shRNA (Setbp1-sh) and control shRNA (NC-sh); right panel, representative Western blot analysis of Setbp1 and actin protein in the same infected cells at 72 hours after infection. Relative Setbp1 protein levels after normalization to actin levels in the same sample are indicated. (B) Mean and SD of colony formation potential in the presence of SCF and IL-3 (left panel) and Western blotting analyses (right panel) of S3 cells at 48 and 72 hours, respectively, after infection with GFP-specific shRNA (GFP-sh) and control shRNA (NC-sh). (C) Cell cycle distribution of S3 cells infected with GFP-specific and control shRNA determined by PI-staining at 96 hours after infection. The mean and SD of each phase is shown (*P < .05).