ERBB2 and malignant colon neoplasm: Next, we selected multiple target cell lines for testing cytotoxicity: the lymphoblast K562 cell line ectopically expressing high or low HER2 (Fig. 3c), the ovarian cancer cell line SKOV3 expressing high HER2 and the colon cancer cell line HT29 expressing low HER2 (Fig. 3d).