miR-1911-3p Regulates Malignant Biological Behaviors and Glycolytic Activity of Triple-Negative Breast Cancer via FBLN5.

Background and Objectives: Based on previous reports demonstrating the clinical potential of miR-1911-3p in breast cancer, its function and mechanisms in the development of TNBC were investigated, aiming to identify a novel biomarker. Materials and Methods: Paired tissues were sampled from 128 TNBC patients, and miR-1911-3p levels were compared between tumor and normal tissues. The clinical significance of miR-1911-3p was evaluated from the perspective of disease severity and patients' prognosis. In vitro, the regulatory effects of miR-1911-3p on the malignant biological behaviors were assessed based on cell growth, motility, and glycolytic activity in MDA-MB-231 and HCC1806 cells. The mechanism evaluation was performed focusing on FBLN5 through luciferase reporter assay and related reversal experiments by co-regulating miR-1911-3p and FBLN5. Results: Significant upregulation of miR-1911-3p was observed in tumor tissues of TNBC patients (fold change of 1.35), which was associated with advanced TNM stage, higher Ki67 levels, and occurrence of lymph node metastasis. miR-1911-3p (HR = 3.036) was identified as an independent prognostic factor predicting 5-year recurrence-free survival (log‑rank Conclusion: miR-1911-3p was identified as an independent prognostic biomarker for TNBC. Different from previously reporter miRNAs, miR-1911-3p regulated glycolytic activity-dependent cell growth and motility by targeting FBLN5, indicating its potential in serving as therapeutic target for TNBC.