PDGFRA and glioblastoma: Furthermore, dog GBM models are possibly more representative of human GBM, with TP53, EGFR, PDGFRα, and IGFBP2 GBM markers being overexpressed in dog GBM, (Higgins et al., 2010), as well as cancer stem cell (CSC) and associated CD133 being present in dog GBM (Stoica et al., 2009).