Figure 7.
(A) Immunoblot analysis of MCF-7 (PIK3CA-mutant, low p-AKT) and T47D cells (PIK3CA-mutant, high p-AKT) stably expressing shRNAs against GFP (control) or PDK1. Antibodies recognizing phospho-AKT (T308), AKT1, phospho-SGK3 (T320), SGK3, phospho-PKC ζ (T410), PKC ζ, phospho-RSK (S227), RSK2, phospho-p70 S6 kinase (T229), p70 S6 kinase, and actin were used. (B) Immunoblot analysis of SGK3 phosphorylation at Thr320 (p-SGK3(T320)) in the absence or presence of LY294002 is shown for MCF-7 and HCT-15 cells (PIK3CA-mutant, low p-AKT). (C) Immunoblot analysis of SGK3 phosphorylation (p-SGK3(T320)) across a panel of PI3K pathway “wild-type”, PTEN-null or PIK3CA-mutant cancer cell lines. Non-transformed lines (MCF-10A and MCF-12A) are included as negative controls (NS: non-specific band).