In the experiments summarized in Supplementary Table S3, we assessed the cytotoxic potencies of HMA and LLC1 toward Met-1 (triple-negative), NDL (HER2-positive), and 4T1 (triple-negative) murine breast cancer cells, as well as UCDK9MM3 (melanoma), UCDK9OSA29 (osteosarcoma), and D17 (osteosarcoma) canine tumor cell lines. Here, ERBB2 is linked to breast cancer.