ß1 Integrin as a Prognostic and Predictive Marker in Triple-Negative Breast Cancer.

ABSTRACT

Triple negative breast cancer (TNBC) displays higher risk of recurrence and distant metastasis. Due to absence of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2), TNBC lacks clinically established targeted therapies. Therefore, understanding of the mechanism underlying the aggressive behaviors of TNBC is required for the design of individualized strategies and the elongation of overall survival duration. Here, we supported a positive correlation between ß1 integrin and malignant behaviors such as cell migration, invasion, and drug resistance. We found that silencing of ß1 integrin inhibited cell migration, invasion, and increased the sensitivity to anti-cancer drug. In contrast, activation of ß1 integrin increased cell migration, invasion, and decreased the sensitivity to anti-cancer drug. Furthermore, we found that silencing of ß1 integrin abolished Focal adhesion kinese (FAK) mediated cell survival. Overexpression of FAK could restore cisplatin-induced apoptosis in ß1 integrin-depleted cells. Consistent to in vitro data, ß1 integrin expression was also positively correlated with FAK (p = 0.031) in clinical tissue. More importantly, ß1 integrin expression was significantly correlated with patient outcome. In summary, our study indicated that ß1 integrin could regulate TNBC cells migration, invasion, drug sensitivity, and be a potential prognostic biomarker in TNBC patient survival.