For example, 80% of GBM cases harbor either an activating mutation or a copy number increase of the epidermal growth factor receptor (EGFR).37 Despite this, clinical trials using small molecules that inhibit EGFR have failed to achieve improved outcomes for GBM patients.2 Although drug resistance is a major issue in chemotherapy, another limitation of targeted therapies is likely due to the redundancy of signaling pathways38 where inhibition of single factors or pathways has limited effect owing to compensation by other pathways. This evidence concerns the gene EGFR and glioblastoma.