EGFR and glioblastoma: Integrated genomic/transcriptome and epigenomic analysis resulted in a gene expression-based molecular classification of GBM into classical, mesenchymal (MES), proneural (PN), and neural subtypes, characterized by aberrations and gene expression of the epidermal growth factor receptor (EGFR), neurofibromatosis Type 1, and platelet-derived growth factor receptor a (PDGFRa).