PIK3CA and glioblastoma: Key members of the gene network,including vascular endothelial growth factor A (VEGFA),epidermal growth factor (EGF), and the catalytic subunitA of phosphatidylinositol-4,5-bisphosphate-3-kinase(PIK3CA), have been identified as important genetic markersof glioblastoma involved in angiogenesis.