CDKN2C and medulloblastoma: In addition, enforced expression of N-Myc in cerebellar granule neuron precursors (CGNPs) collaborates with the loss of Trp53 and Cdkn2c (p18Ink4c) [86], as well as the loss of Ptch1 [87] to accelerate SHH medulloblastoma development in mice.