Down-regulated microRNA-124 expression as predictive biomarker and its prognostic significance with clinicopathological features in breast cancer patients.

BACKGROUND

MicroRNAs (miRNAs) have been documented as playing important roles in cancer development. In this study, we investigated to clarify the clinicopathological significance and prognostic value of miR-124 in breast cancer.

METHODS

Quantitative Real-time PCR method was used to assess the expression levels of miR-124 in breast cancer patients and the association of miR-124 expression levels with the clinicopathological characteristics in breast cancer patients. Survival and Multivariate Cox proportional hazards model analysis was used to evaluate whether the miR-124 expression level and various clinicopathological characteristics were independent prognostic marker for breast cancer patients.

RESULTS

We found that the lower expression of miR-124 in breast cancer specimens compared with corresponding adjacent normal breast tissues P < 0.05. Results showed that decreased expression of miR-124 was significantly related to advanced clinical stage (stage III and IV) (P = 0.021) and positive lymph node-metastasis (P = 0.011). Patients with low expression of miR-124 had significantly shorter overall survival (70.2 %) than patients who had cancers with high miR-124 expression (29.8), (logrank test P = 0.021). Moreover, Multivariate Cox proportional hazards model analysis indicated that lowr miR-124 expression was found to be independently linked to poor survival of patients with breast cancer and other factors were not significantly associated with survival of patients.

CONCLUSION

Our data suggested that decreased expression of miR-124 has prognostic value in breast cancer and may serve as a prognostic marker for breast cancer, and also downregulation of miR-124 was inversely associated with the lymph node metastasis in breast cancer.