EGFR and glioblastoma: To test if inhibiting steady-state levels of endogenous EGFR alters TERT expression, we treated four GBM cell lines and four GBM patient-derived lines (Fouse et al., 2014; Sarkaria et al., 2006) with three distinct EGFR inhibitors or with two distinct short hairpin RNAs (shRNAs) targeting EGFR.