EGFR and glioblastoma: The molecular diversity of these GSCs reflects high intertumoral heterogeneity of GBM: for instance, western blotting (WB) revealed distinct expression profiles of receptor tyrosine kinases–EGFR in SD1, EGFR and MET in SD2, and PDGFRα in SD3 and SD4, and RNA-sequencing (RNA-seq) analysis indicated three different transcriptional subtypes28 (Supplementary Fig. 1a, b).