Treatment with IL-13Rα2/TGF-β CAR-T cells resulted in increased T-cell infiltration and reduced levels of suppressive myeloid cells in the tumor-bearing brain compared to conventional IL-13Rα2 CAR-T cells, leading to improved survival in both patient-derived GBM xenografts and syngeneic murine models. This evidence concerns the gene TGFB1 and glioblastoma.