Even though more than >70% of GBM patients have overexpressed RTK [164], such as EGFR and PDGFRA with active downstream pathways (e.g., PI3K/AKT/mTOR) [165], clinical trials including RTK inhibitors, such as Cetuximab, an FDA-approved anti-EGFR [166] antibody, or Imatinib (anti-PDGFRA inhibitor), have failed. Here, PIK3CA is linked to glioblastoma.