CDKN2A and glioblastoma: In these regions, the CNVs of some genes were observed in most patients, including many genes that have been confirmed to be important in the occurrence and development of GBM, such as EGFR, CDKN2A/CDKN2B, and MTAP (Lopez-Gines et al., 2010; Feng et al., 2012; Xu et al., 2017).