CUL5 and neoplasm: Consistently, the CUL5 KO CAR-T cells not only showed significantly higher acute tumor cell killing ability of NALM6 B cells in culture than the NC cells (Fig. 6f) but also maintained the higher killing ability and viability after repeated stimulation (Supplementary Fig. 7e), demonstrating improved stemness potential, cytotoxic activity, and viability of CD8 + T cells upon CUL5 KO.