Low levels of tau expression were associated with a greater response to treatment when patients with breast cancer received combinatorial treatment with paclitaxel, 5-fluorouracil, doxorubicin, and cyclophosphamide (P/FAC) [60], and high tau expression showed a significant association with poor response to paclitaxel and trastuzumab chemotherapy in patients with HER2-positive advanced breast cancer [64]. This evidence concerns the gene ERBB2 and breast cancer.