MicroRNA-432 Acts as a Prognostic Biomarker and an Inhibitor of Cell Proliferation, Migration, and Invasion in Breast Cancer.

BACKGROUND: Accumulating studies have demonstrated that microRNAs (miRNAs) are involved in the progression of various cancers. This study aimed to investigate the potential clinical and functional role of miR-432 in breast cancer.

MATERIALS AND METHODS: We evaluated the expression of miR-432 in 117 breast cancer samples and paired nontumor tissue samples, as well as 4 breast cancer cell lines using RT-qPCR analysis. Kaplan-Meier survival curve and multivariate Cox regression analysis were used to evaluate the prognostic significance of miR-432 in breast cancer patients. CCK-8 assay and Transwell assays were used to evaluate the biological function of miR-432 in the progression of breast cancer.

RESULTS: miR-432 was downregulated in breast cancer tissues and cell lines, and its exotic expression was associated with tumor size, lymph node metastasis, and TNM stage. In addition, breast cancer patients with low miR-432 expression exhibited a shorter overall survival outcome. Further experiments revealed that overexpression of miR-432 inhibited the cell proliferation, migration, and invasion of breast cancer cells, while knockdown of miR-432 promoted these cellular activities. AXL was a direct target of miR-432 in breast cancer cells.

CONCLUSION: The present study suggested that miR-432 may be a tumor suppressor in the progression of breast cancer through inhibiting cell proliferation, migration, and invasion by targeting AXL. And miR-432 might be a prognostic biomarker and therapeutic target for the treatment of breast cancer. This study provided a novel insight into breast cancer prognosis and treatment.