IL13RA2 and glioblastoma: Interleukin‐13 receptor alpha 2 (IL13Rα2), epidermal growth factor receptor variant III, human epidermal growth factor receptor 2 (HER2) and erythropoietin‐producing hepatocellular carcinoma A2 (EphA2) are some examples of GBM‐specific antigens that have been employed in CAR design.104