To understand whether 40A3Bz dnTGFβRII CAR-Ts would show antitumor activity in a lower, more heterogeneous STEAP2-expressing 22RV1–TGF-β model, xenograft tumor–bearing mice were dosed with 3 × 106, 7 × 106, or 12 × 106 CAR-Ts per mouse. The gene discussed is TGFB1; the disease is neoplasm.