EGFR and glioblastoma: In GBM, activated EGFR promotes PI3K/Akt (phosphatidyl-inositol-Kinase/Akt), MAPK/ERK (mitogen-activated protein kinases/extracellular signal-regulated kinases), signal transducer and activator of transcription 3 (STAT3), and phospholipase C gamma signalling cascades.