MicroRNA‐487b‐3p Represses Cell Functions and Epithelial‐Mesenchymal Transition and Acts as a Prognostic Predictor for Breast Cancer

ABSTRACT Our aim was to ascertain the clinical implications of microRNA‐487b‐3p (miR‐487b‐3p) in breast cancer. MiR‐487b‐3p level was measured in breast cancer tissues ( n = 102) and adjacent noncancerous tissues ( n = 102) using quantitative real‐time polymerase chain reaction (qRT‐PCR). Kaplan‐Meier method and Cox regression analysis were conducted for evaluating the clinical performance of miR‐487b‐3p. Cell counting kit‐8 (CCK‐8) and Transwell assay were utilized for cellular functions. Bioinformatics tools and luciferase reporter assay were performed for the target predication and confirmation. MiR‐487b‐3p was remarkably diminished in breast cancer tissues. Aberrant miR‐487b‐3p was tightly in relation to Ki67 ( p = 0.003), human epidermal growth factor receptor (HER2) status ( p = 0.025), tumor node metastasis (TNM) stage ( p = 0.028) and lymph node metastasis ( p = 0.002). Moreover, a better progression free survival rate was found in patients expressing high miR‐487b‐3p ( n = 51, p < 0.001) than those with low expression ( n = 51). Additionally, miR‐487b‐3p was an independent predictor for the prognosis of breast cancer ( p < 0.001; HR = 2.971; 95% CI = 1.721–5.131). Enforced miR‐487b‐3p expression obviously restrained cell activities and epithelial‐mesenchymal transition (EMT), while apposite effects were observed posttransfection with miR‐487b‐3p inhibitor ( p < 0.001). Notably, low‐density lipoprotein receptor‐related protein 6 (LRP6) was a potential target gene of miR‐487b‐3p, an adverse relevance of which was discovered ( r = −0.5811; p < 0.001). MiR‐487b‐3p was an underlying indicator for the prognosis in breast cancer. It impacted on cell activities and EMT via regulating LRP6 in breast cancer development. Clinical trial registration: Not applicable.