SOX2 and central nervous system cancer: Immunoblot analysis of transcription factors involved in the development of gliomas (OLIG2, MYC, SOX2 and PAX6)51, 52, 53 showed a specific decrease in expression in PTEN-deficient cells (GSC11, GSC23, HK281) compared with PTEN-WT cells (GBM6, TS675, GBM39, TS543) (Supplementary Fig. 12b,c), suggesting that DAXX disruption in PTEN-null/GBM-PDXs affects the expression of transcription factors implicated in gliomagenesis.