AKT1 and central nervous system cancer: Enzastaurin, a cyclic bisindole maleimide, is an oral serine/threonine kinase inhibitor that specifically inhibits the protein kinase C and phosphatidylinositol 3‐kinase and protein kinase B (PI3K/AKT) signalling pathways, leading to cell apoptosis, the inhibition of cell proliferation and anti‐tumour‐induced angiogenesis.45, 46 In 2006, the EU and FDA approved enzastaurin for the treatment of GBM.47 In 2010, a phase I/II clinical trial showed that enzastaurin exhibited some anti‐tumour activity against recurrent gliomas, but it cannot be used for monotherapy.48