Taking into account these observations and the uncertainty regarding whether EGFR amplification and protein overexpression, which are common in GBM, are individually sufficient as definitive causes of cancer development, we hypothesized that aberrant expression or inactivation of MIG6—an EGFR‐negative feedback inhibitor encoded by ERRFI1—may potentially serve as an additional genomic alteration leading to tumorigenesis, particularly within the genetic conditions characterized by such EGFR alterations. The gene discussed is ERRFI1; the disease is glioblastoma.