A recent pre-clinical study directly compared efficacy of a second generation IL-13Rα2 CAR transduced into patient-derived CD8+ or CD4+ T-cells and found CD4+ CAR T-cells demonstrated enhanced tumor killing and persistence compared with CD8+ and a mixed CD4+/CD8+ population in a xenograft model of GBM (159). This evidence concerns the gene IL13RA2 and glioblastoma.