ABCB1 and breast carcinoma: Quercetin has been reported to kill many types of cancer cells, including human breast cancer MCF-7 cells (114), NSCLC A549 cells (115), ovarian cancer cells (116), etc. Quercetin is able to block the function and expression of ABCB1 and ABCC1, ABCC2 (112, 117, 118).