ERBB2 and breast cancer: For each specific breast cancer subtype, we observed that this signature was significantly overexpressed compared with normal tissue (Supplementary Figure S3H), and was associated with detrimental RFS in all subtypes (Figure 5A) (luminal A, HR: 1.57, CI 1.23–2.01; log rank p = 3 × 10−4; luminal B, HR:3.78, CI 1.64–8.69, log rank p = 0.00079; HER2+, HR: 3.2, CI 1.45–7.08, log rank p = 0.0024; basal, HR: 1.78, CI 1.27–2.49, log rank p = 0.00063).