OLIG2 and central nervous system cancer: nf1a+/−/nf1b−/− mutants in the p53zdf1/zdf1 background developed brain tumors in 33 weeks, with characteristic markers (sox10/Olig2/Gfap) of diffuse high-grade gliomas and hyperactivation of ERK and mTOR pathways, similar to mouse models and human gliomas.