Figure 1 illustrates the histology of patient- and xenograft-derived tumors for each of the following BC subtypes: luminal human breast cancer xenograft (HBCx-3), triple-negative (HBCx-8, HBCx-12A and HBCx-10), HER2+ (HBCx-5), and lobular (HBCx-19). The gene discussed is ERBB2; the disease is breast cancer.