Figure 6

NDRG2 suppression of c-Myc stabilization is mediated by AKT/GSK3β pathway. (A) GSEA analysis predicts the gene enrichment in PI3K-Akt pathway in MC3 cells with or without NDRG2 expression. (B) Levels of indicated proteins in MC3 cells with or without NDRG2 expression. (C-F) We overexpressed the wild type or activating form of Akt1 (myr-Akt1) in NDRG2-overexpressing MC3 cells. (C) The indicated proteins levels were determined by western blotting. (D) Immunoprecipitation was performed to determine the interaction between c-Myc and Fbw7 in indicated MC3 cells. After the Fbw7 protein were immunoprecipitated with an anti-Fbw7 antibody, indicated proteins were detected by western blotting. (E-F) c-Myc enrichment on ASCT2 promoter (E) and the activities of wild-type and E-box-mutant ASCT2 promoter (F) were determined respectively. (G, H) c-Myc enrichment on ASCT2 promoter (G), and the activities of wild-type and E-box-mutant ASCT2 promoter (H) were determined in wild-type or NDRG2-/- MEF cells, respectively. Data are expressed as means ± SD (n = 3). (I) The proposed mechanism of NDRG2 action in regulation of Akt/c-Myc axis and ASCT2 expression. **, P <0.001.