The levels of NRF2 expression correlated with levels of area of under the curve (AUC) for paclitaxel, 5-FU (fluorouracil), tamoxifen, and fulvestrant in ER-positive/HER2-negative breast cancer cell lines (CAMA1, EFM19, HCC1428, HCC1500, KPL1, MCF7, MDAMB175VII, MDAMB415, T47D, and ZR751) (Figure 5A, r = 0.88 [p = 0.02], r = 0.86 [p < 0.01], r = 0.75 [p < 0.05], and r = 0.96 [p < 0.01], respectively). This evidence concerns the gene ESR1 and breast cancer.