Figure 6

Akt-mediated GSK-3 β inactivation also involves in ABT-263-induced stabilization of Mcl-1 protein. (A) HCC cells were treated with 5 μM ABT-263 for 18 h, then p-Akt (Ser473), p-GSK3β (Ser9) and total GSK3β (t-GSK3β) were detected by Western blot, taking α-tubulin as a loading control. (B) After pretreated with 150nM PI3K/mTOR dual inhibitor NVP-BEZ235 for 2 h, the HCC cells were treated with 5 μM ABT-263 for 18 h. Then p-GSK3β (Ser9) and t-GSK3β, Mcl-1, PARP and cleaved PARP were analyzed by Western blot. (C) After pretreated with 10 μM ERK1/2 inhibitor U0126 for 2 h, the HCC cells were treated with 5 μM ABT-263 for 18 h. Then p-GSK3β (Ser9) and t-GSK3β were detected by Western blot. (D) After pretreated with 150nM NVP-BEZ235 for 2 h, the HCC cells were treated with 5 μM ABT-263 for another 24 h. Then the total cell death was analyzed by trypan blue exclusion assay. Data were expressed as mean ± SD from three independent experiments. (**: P < 0.01, ***: P < 0.0001).