shRNA-mediated silencing of ERG attenuates the growth of human leukemia cell lines. (A) Western blot analysis of ERG expression in cell lines infected with shRNA viruses for luciferase (control) and (ERG(1) and ERG(2). Two different viruses were used for ERG silencing. (B) Typical FACS analysis of cells transduced with the shRNA viruses. Results obtained with Reh cells are presented. Cells were infected with shRNA viruses that coexpress GFP, and percentage of GFP in the bulk liquid culture was monitored over time. (C) Percentage of GFP in the bulk liquid culture of cells infected with the indicated shRNA viruses. K562, NB4, MegA2, Jurkat, JM, Nalm1, Nalm6, and Reh cells were used. The ratio of percentage of GFP for luciferase to percentage of GFP for ERG is presented along with the days elapsed after monitoring began. (D) Growth curves of the indicated cells infected with shRNA viruses for luciferase (○) and ERG [ERG(1), ●; ERG(2), ■]. (E) Growth curves of Reh and Jurkat cells infected with shRNA viruses for luciferase and ERG(1) and ERG(2). The number of viable (●) and dead (○) cells is presented during 5 days of culturing. The initial input cell number was 1 × 10⁵.