MIR-518a-5p Targets ZEB2 to Suppress the Migration and Invasion of Breast-cancer Cells.

Context: Although great progress has occurred in breast cancer (BC) treatment, including chemotherapy, chemoradiotherapy, and surgical resection, the rate of patients' survival is still unsatisfactory. Multiple genes and factors have proven to contribute to BC's occurrence. Thus, it's urgent to explore the molecular mechanisms in the development and progression of BC and find possible targets for therapy.

Objective: The study intended to assess the mechanisms of miR-518a-5p's effect on BC by targeting the zinc finger E-box-binding homeobox 2 (ZEB2) gene.

Design: The research team designed a laboratory study and retrospective analysis.

Setting: The study took place in the Department of Breast Surgery at the Xingtai People's Hospital in Xingtai, Hebei, China.

Outcome Measures: The study measured the miR-518a-5p expression in BC tissues and normal tissues using a real-time quantitative reverse transcription (qRT)-polymerase chain reaction (PCR) test. The research team purchased the BC cells MDA-MB-231 and MCF-7 and measured the effects of the miR-518a-5p on BC cell activity as well as epithelial-mesenchymal transition (EMT) ability, using cell scratch tests and Transwell assays. The team assessed the ZEB2 protein expression and verified the targeting relationship using a Dual-Luciferase Reporter assay.

Results: The miR-518a-5p expressed was low in the BC tissues and cell lines compared with adjacent normal tissues (P < .05). Overexpressing the miR-518a-5p inhibited BC-cell migration and invasion (P < .05). Moreover, the ZEB2 was the target gene for the miR-518a-5p. The Luciferase assay verified that the miR-518a-5p directly targeted the ZEB2 in BC cells (P < .05). The Transwell invasion assay, western blot analysis, and wound healing assay also showed that the miR-518a-5p inhibited BC cells by targeting ZEB2 (P < .05).

Conclusions: The miR-518a-5p suppressed BC migration, invasion, and process of EMT by regulating ZEB2. In the future, this method may be a new option for BC diagnosis and treatment. An in-depth understanding of the role of the miR-518a-5p in BC can help clinicians to understand the pathogenic mechanism of breast cancer more accurately.