Increased expression of miR-330-3p: a novel independent indicator of poor prognosis in human breast cancer.

OBJECTIVE: Previous study has reported that miR-330-3p was highly expressed in breast cancer (BC) patients. However, the effect of miR-330-3p in BC progression remains largely unclear. The purpose of this study was to investigate the clinical significance of miR-330-3p expression in BC.

PATIENTS AND METHODS: The expression of miR-330-3p was detected by quantitative Real-time PCR in BC tissues and matched normal breast tissues. The association of miR-330-3p expression with clinicopathological factors of BC patients was also analyzed by x2-test. Prognosis value of patients with BC was assessed by Kaplan-Meier method and Cox proportional hazards model, respectively.

RESULTS: Quantitative real-time PCR analysis showed that the expression level of miR-330-3p was significantly higher in BC specimens than that in corresponding noncancerous tissues (p < 0.01). The levels of miR-330-3p were positively correlated with the status of TNM stage (p = 0.011) and lymph node metastasis (p = 0.006). Kaplan-Meier analysis revealed that 5-year overall survival of BC patients with high miR-330-3p expression was shorter compared to those patients with low miR-330-3p expression (p < 0.0001). Moreover, univariate and multivariate regression analysis demonstrated that miR-330-3p was an independent prognostic factor in BC.

CONCLUSIONS: Our data suggest that miR-330-3p upregulation maybe concurrently associated with prognosis in patients with BC, suggesting that miR-330-3p may be a potential prognostic biomarker and therapeutic target for patients with BC.