To verify the progression routes of transition from DCIS to clinical subtypes of IDC, four human breast cancer cell lines (including T47D (IDC‐luminal A, HR+/HER2‐), BT‐474 (IDC‐luminal B, HR+/HER2+), and SKBR‐3 (IDC‐HER2‐enriched, HR‐/HER2+), and MDA‐MB‐231 (IDC‐TNBC, HR‐/HER2‐)[66]) were selected to better mimic the pattern of IDC subtypes identified in our proteomic data. The gene discussed is ERBB2; the disease is ductal breast carcinoma in situ.