RPS6KB1 and glioblastoma: In U87 and LN229 GBM lines, CID613034 markedly inhibited phosphorylation of known mTORC2 substrates such as phospho-S473-AKT, phospho-T346-NDRG1 and phospho-S657-PKCα, while having no discernible effect on the levels of phospho-T389-S6K, a mTORC1 specific phospho-site.