GSK-626616 (serum-deprived HeLa cells) reduces EGF-induced phosphorylation of PRAS40 at Thr246. GSK-626616 enhances the binding of PRAS40 to mTORC1[2]. GSK-626616 abolishes the phosphorylation of S6K1 at Thr389 in nonstimulated HeLa cells. GSK-626616 reduces the phosphorylation of S6K1 at Thr389 in EGF- and insulin-stimulated HeLa cells, showing that mTORC1 activity is impaired[2].