Low expression of miR-409-3p is a prognostic marker for breast cancer.

OBJECTIVE: The present study aimed to clarify the expression pattern and prognostic role of miR-409-3p in breast cancer patients. MATERIALS AND METHODS: miR-409-3p levels in breast cancer tissues were tested by qRT-PCR. The chi-square test and Fishers exact tests were used to examine the associations between miR-409-3p expression and the clinicopathological characters. Overall survival (OS) was estimated using the Kaplan-Meier method. The univariable and the multivariable Cox regression analyses were used to evaluate independent prognostic factors. RESULTS: miR-409-3p expression in breast cancer specimens was observed to be decreased compared with matched normal breast tissues (p < 0.01). Additionally, low miR-409-3p expression in breast cancer tissues was significantly associated with the advanced TNM stage (p = 0.004), lymph node metastasis (p = 0.001), and poorer pathological differentiation (p = 0.026). The patients in the low miR-409-3p group had a shorter overall survival than those in the high miR-409-3p group (p < 0.001). Furthermore, the univariate and the multivariate analyses showed that miR-409-3p expression was an independent predictor of overall survival (p < 0.05). CONCLUSIONS: Our results revealed that miR-409-3p was related to the prognosis of patients with breast cancer and might be a promising predictor of miR-409-3p recurrence.