ERBB2 and breast cancer: To assess the generalizability of our computational framework and experimental observations, we generated and tested three additional breast cancer cell lines from diverse molecular backgrounds30: 21MT1 (Basal subtype, HER2+), HCC1143 (Basal subtype, HER2-) and MDAMB157 (Claudin-low subtype, HER2-) (Supplementary Figs. 5–7).