Hu et al. Journal of Experimental & Clinical Cancer Research 2010, 29:154 http://www.jeccr.com/content/29/1/154 Page 6 of 8 Figure 4 Inhibition of GSK-3b induces apoptosis in ALL but not control cells. (A) ALL cells were treated for 48 h with DMSO or SB216763 at indicated concentrations. Cells were assayed for apoptosis using Annexin V-PE/7-AAD staining by flow cytometry. (B) We found that inhibition of GSK-3b in ALL cells consistently resulted in a dose-dependent increase in the number of apoptotic cells. (C) ALL cells were treated for 48 h with NaCl or LiCl at indicated concentrations, then assayed for apoptosis using Annexin-V-PE/7-AAD staining as determined by flow cytometry. (D) Each GSK-3b inhibitor was added to control BMMC at the initiation of the culture at a variety of concentrations as indicated on the graph. LiCl and SB216763 had no significant effect on cell apoptosis in normal BMMC. Columns, mean; bars, SD. *P < 0.05, **P < 0.01 vs. control. All assays were performed in triplicate.