AKT1 and gastrointestinal stromal tumor: Evaluations of the three FDA- and EMA-approved drugs for the treatment of GIST, imatinib, sunitinib and regorafenib, demonstrated that each drug inhibited oncogenic KIT and downstream AKT phosphorylation in a dose-dependent manner in GIST cells containing only KIT primary exon 11 mutations (GIST-T1, GIST430 and GIST882) without KIT secondary mutations (Fig. 1a).