CDKN2A and glioblastoma: Mutations of p53, p16INK4a deletion, EGFR amplification, and PTEN mutations show inverse associations with each other, except for a positive correlation between p16INK4a deletion and EGFR amplification.2,115,116 Once a thorough road map for GBM oncogenomics is designed, it should aid in the development of more rational and more effective targeted therapies.