CEBPB and acute myeloid leukemia: To identify the growth regulatory ability of GSK3β in AML cells, we demonstrated that SB216763 (GSK3β inhibitor) increased the protein levels and mRNA levels of C/EBPβ (Fig. 5C), as well as C/EBPβ and CD11b were further increased following SB combination with ATRA in U937 cells (Fig. 5D).