KLRK1 and neoplasm: CAR transduced natural killers (NK) cells (e.g., DLL3 CAR NK-92 cells), which complements CAR-T cell therapy have attracted attention toward tumor efficacy as configured with the NKG2D transmembrane structural domain and the co-stimulatory molecule 2B4-CD3 structural domain which might potentially enhance the cytotoxicity of NK cells, a preliminary anti-tumor activity in preclinical models with favorable tumor infiltration68, and the efficacy of CAR-NK in relapsed/refractory SCLC is being evaluated in a currently.