In conclusion, these data indicated that in contrast to parental NK-92MI or CD19-CAR NK cells, both CLDN6-CAR NK cells exhibited robust cytotoxicity and cytokine production as well as NK cell activation after they encountered target CLDN6-positive tumor cells in vitro, which suggests that CLDN6-CAR NK cells can elicit strong immune responses and antitumor activity against ovarian cancer cells with CLDN6 expression. The gene discussed is CLDN6; the disease is ovarian cancer.