ERBB2 and breast carcinoma: Large differences in intrinsic subtype proportions are evident across all mouse models tested in comparison with human intrinsic breast cancer subtype proportions, with METABRIC intrinsic subtype proportions at 35% luminal A, 24% luminal B, 11% HER2+, 11% claudin-low, 11% basal, and 8% normal-like.