AKT1 and melanoma: To confirm that melanoma cells used in our system are sensitive to PI3K/Akt/mTOR inhibition, we treated melanoma cells with specific inhibitors of AKT (MK-2206, a highly selective Akt1/2/3 inhibitor), PI3K (ZSTK474, a class I PI3K isoforms inhibitor) and mTOR (KU-0063794, a specific dual-mTOR inhibitor of mTORC1 and mTORC2).