When the tumor volume reached 100 mm3 (day 7), mice bearing the tumor were randomly allocated into four groups (n = 3) and assigned to receive one of the following intravenous injections: (1) sterile PBS, (2) 6 × 106 NK-92 cells, (3) 6 × 106 HER2-CAR-NK cells or (4) 6 × 106 sPD-1-CAR-NK cells. Here, ERBB2 is linked to neoplasm.