ERBB2 and breast cancer: In addition to modulating ADCC, anti-HER2 antibodies may also interact with adaptive immune responses.73 In a murine model, the activity of anti-HER-2 was dependent on cytotoxic T-cells and interferon secretion, and was improved in combination with anti-PD-1.74 One additional consideration for HER2-positive breast cancer is the antigenic potential of the HER2 protein.