DNA-PKcs controls phophsporylation of Akt and GSK3 β. (A) Phosphorylation of Akt and GSK3 β was depressed in HeLa cells transfected with a DNA-PKcs specific siRNA construct (HeLa-H1). (B) Phosphorylation level of Akt and GSK3 β was lower in DNA-PKcs deficient M059J cells than in DNA-PKcs efficient M0591K cells. (C) & (D) Subchronic exposure to low dose TCDD for 2 weeks (C) or 4 weeks (D) upregulated the phosphorylation level of Akt and GSK3 β along with increased expression DNA-PKcs and c-Myc. (E) Depression of TCDD-increased DNA-PKcs by DNA-PKcs specific siRNA led to decreased phosphorylation level of Akt and GSK3 β. L02/TCDD-H1 and L02/TCDD-NC cells were described in Fig. 2(D).