MicroRNA-10b expression in node-negative breast cancer-correlation with metastasis and angiogenesis.

Metastasis accounts for the majority of cases of mortality in patients with axillary lymph node-negative (ANN) breast cancer. Angiogenesis is an essential component of the metastatic pathway. Studies regarding microRNA (miR)-10b expression in patients with ANN breast cancer and the function of angiogenesis in breast cancer remain scarce. The present study was performed in order to determine the biological significance of miR-10b, and investigate the association between miR-10b and microvessel density (MVD) measured in ANN breast cancer. miR-10b expression and immunohistochemical analysis for MVD were assessed in 195 patients with ANN of invasive ductal carcinoma, including 65 cases with distant metastasis 'poor group', and 130 cases without any recurrence 'good group'. miR-10b expression was higher in the 'poor group' (73.8%) compared with that in the 'good group' (51.5%; P=0.003). Multivariate logistic regression demonstrated that miR-10b retained independent prognostic significance for distant metastasis along with MVD and vascular invasion. Among 195 patients, miR-10b expression was significantly associated with tumor grade, tumor size and molecular subtypes (P<0.05). In addition, miR-10b expression was positively associated with the MVD count (r=0.370; P<0.001), tumor grade (r=0.168; P=0.019) and tumor size (r=0.175; P=0.014). The results of the current study suggest that miR-10b is a useful marker for predicting metastasis and angiogenesis in ANN breast cancer.