The endogenous Egfr gene was also upregulated (mean log2 fold change = 3.71) in both brain and spinal tumors, suggesting both mutant EGFR and wild-type Egfr expression are advantageous to tumor growth (Fig. 2d), consistent with previous reports suggesting collaboration between the two as observed in human GBMs [38]. This evidence concerns the gene EGFR and neoplasm.