Tau proteins expressions in advanced breast cancer and its significance in taxane-containing neoadjuvant chemotherapy.

Tau is a microtubule-associated protein and expressed in normal breast epithelial cells and breast cancer. Tau expression in breast cancer may be important for chemotherapy optimization. This study is to investigate the expression of Tau in advanced breast cancer and its significance in taxane-containing neoadjuvant chemotherapy. Levels of Tau protein in advanced breast cancer were detected immunohistochemically. The chemotherapeutic efficacy indexes in Tau(-) group, which includes the remission rate, Miller-Payne pathological reactive grade, and pathologic complete response rate, were improved compared with that in Tau(+) group. There was difference in the efficacy indexes among ER+ subgroups but not among ER- patients. In addition, Tau expression was positively correlated (r = 0.32, P < 0.00). In multivariate analysis, when age, clinical stage, postoperative lymph node metastasis, ER, PR, HER2, Ki-67, TP53, or Tau status were included, postoperative lymph node metastasis and Tau-negative status were identified as independent predictors of pathologic complete response. In conclusion, negative Tau protein expression may be an effective predictor for taxane-containing neoadjuvant chemotherapy, especially in ER+ subgroups. Further study on the molecular mechanism and utility of Tau for individualizing adjuvant chemotherapy is warranted.