The lung tissues of mice in the blank group and CD19-CAR NK group were covered with metastatic lung nodules of different sizes, most of which were bright and cystic, consistent with the cystic characteristics of ovarian cancer metastasis, while the lung nodules in the CLDN6-CAR1 NK group were scattered and few in number (Fig. 5K and 5L). The gene discussed is CLDN6; the disease is ovarian cancer.