While the proportion of the NK cell population (CD45+ CD3− CD56+) was unaltered in the co-cultures of the two cancer cell lines (Figure 5B and Supplementary Figure 4B), both single and dual HER2 blockade led to a significant reduction in the CD16+ NK cell population in SKBR3 co-cultures (Figure 5B). Here, NCAM1 is linked to cancer.