CDKN2A and cancer: Many efforts have been made since The Pan Cancer project of TCGA deepened on the high frequency of alterations in the receptor tyrosine kinase/PI3K/PTEN/AKT/mTOR-signaling pathway (present in 88% of GB cases), along with the p53/MDM2/p14ARF molecular pathway (87%) and the CDKN2A/CDK4/6/retinoblastoma signaling pathway (78%) [1,9,10,11,12].