Microtubule-Associated Protein Tau, α-Tubulin and βIII-Tubulin Expression in Breast Cancer

BACKGROUND The microtubule-associated protein Tau binds to both inner and outer surfaces of microtubules, leading to tubulin assembly and microtubule stabilization. The aim of this study was to evaluate the significance of Tau, α-tubulin, and βIII-tubulin expression in breast carcinoma and to assess their relationships with disease progression in the context of taxane treatment. METHODS Immunohistochemical expressions of Tau, α-tubulin, and βIII-tubulin were assessed in 183 breast cancer cases. Expression was correlated with clinicopathologic parameters, disease progression and overall survival. RESULTS Tau expression was correlated with lymph node metastasis and estrogen receptor (ER) positivity (p=.003 and p<.001, respectively). Loss of α-tubulin was significantly correlated with distant metastasis (p=.034). Loss of βIII-tubulin was correlated with lymph node metastasis and ER positivity (p=.004 and p<.001, respectively). In taxane-treated cases, Tau expression and loss of α-tubulin and βIII-tubulin expression were related to disease progression (p=.001, p=.028, and p=.030, respectively). Tau expression was associated with a worse survival rate in taxane-treated patients (p=.049). CONCLUSIONS Tau expression and loss of α-tubulin and βIII-tubulin expression were correlated with aggressive behavior in taxane-treated breast cancer. Further evaluation of Tau, α-tubulin and βIII-tubulin may be useful in predicting clinical behavior and seeking therapeutic measures in taxane-based chemotherapy for breast cancer.