EIF2AK3 and neoplasm: Since BEZ235 and ZSTK474 were able to induce similar inhibition of pAKT and pERK in combination with selumetinib, the enhanced inhibition of pS6 with BEZ235 and selumetinib is likely to help explain why this combination was more effective than ZSTK474 and selumetinib at preventing tumor growth in the NZM20 xenograft model.