Upregulation of miR-301a correlates with poor prognosis in triple-negative breast cancer.

Identification of biomarkers is important not only for cancer diagnosis, prognosis and treatment, but also provides new insight into cancer biology. The aim of this study was to evaluate the clinical significance of miR-301a in patients with triple-negative breast cancer (TNBC). The expression level of miR-301a was examined by quantitative reverse transcription polymerase chain reaction in 118 pairs of TNBC and adjacent noncancerous tissues. The relationships between miR-301a expression and clinical features, and prognosis of patients with TNBC were analyzed. miR-301a was upregulated in cancer tissues compared with adjacent noncancerous tissues. Furthermore, the level of miR-301a was positively correlated with tumor size, depth of invasion, TNM stage and LNM. High miR-301a expression was significantly associated with larger tumor size and LNM. Multivariate analysis suggested that miR-301a expression was an independent prognostic factor for the survival of patients with TNBC, and the effect remained significant after further stratified by clinical features. In conclusion, miR-301a may be involved in the progression of TNBC and has strong potential to serve as a biomarker for the prognosis of TNBC.