To figure out whether co-expression of IL-7 enhanced the anti-apoptosis ability of CAR T cells, NKG2D-CAR and NKG2DIL7-CAR T cells were cocultured with PC-3 tumor cells without IL-2 for 7 days and the apoptosis cells was detected by Annexin-V/7AAD staining. This evidence concerns the gene KLRK1 and neoplasm.