KRAS and central nervous system cancer: Then, because single c-Myc and Cdc20 genes are not sufficient to induce glioma in both CDKN2A+/+ and CDKN2A−/− Ntv-a mice, we explored the role of c-Myc and Cdc20 in glioma development in a RCAS/Ntv-a mouse model using the combination of kRas and Akt3.