These cell culture systems facilitated the analyses of the contribution of EGFR/EGFRvIII to a stem-like phenotype, the discovery of an EGFR/EGFRvIII-dependent cellular hierarchy within the stem-like compartment of GBM, and the development of targeted therapy approaches for EGFR/EGFRvIII-positive GS-cells. This evidence concerns the gene EGFR and glioblastoma.