Since we observed that breast cancer samples derived from patients treated with 5-flurouracil and cyclophosphamide showed upregulation of ABCC1 and ABCC3, we further went ahead to check the expression of ABCC1 and ABCC3 upon 5-fluorouracil (3 μM) treatment in breast cancer cell lines. The gene discussed is ABCC3; the disease is breast carcinoma.