Our experiments revealed that both second and third generation HER2-specific CAR NK cells efficiently recognized and killed the CD44− N87 xenografts (Figure 5b, NT vs. all other treatments: *** p < 0.001), and there was no significant difference in tumor suppression between the CAR NK cells and the trastuzumab-redirected NK cells (Figure 5b, NT + TRAST vs. all HER2-CAR NK: n.s.). Here, ERBB2 is linked to neoplasm.