MET and glioblastoma: Conversely, BRAF alterations are rarely found in adult gliomas (92, 93), although activation of the MAPK is seen in 70% of GBM through amplifications or fusions in EGFR/PDGFRA/MET/FGRF1/2/3 genes or mutations in MAPK pathway members particularly NF1, reported in 15% of GBM (45).