SGK1 and meningioma: Here we report distinct activation of the mTORC2 target SGK1, detected by phosphorylation of its substrate NDRG1 (N-myc downstream-regulated gene1) in NF2-null human meningioma cells and NF2-deficient human arachnoidal cells, which remains insensitive to the mTORC1-specific inhibitor rapamycin.