Let-7a-5p, miR-100-5p, miR-101-3p, and miR-199a-3p Hyperexpression as Potential Predictive Biomarkers in Early Breast Cancer Patients

Background: The aim of this study is to identify miRNAs able to predict the outcomes in breast cancer patients after neoadjuvant chemotherapy (NAC). Patients and methods: We retrospec-tively analyzed 24 patients receiving NAC and not reaching pathologic complete response (pCR). miRNAs were analyzed using an Illumina Next‐Generation‐Sequencing (NGS) system. Results: Event‐free survival (EFS) and overall survival (OS) were significantly higher in patients with up-regulation of let‐7a‐5p (EFS p = 0.006; OS p = 0.0001), mirR‐100‐5p (EFS s p = 0.01; OS p = 0.03), miR‐ 101‐3p (EFS p = 0.05; OS p = 0.01), and miR‐199a‐3p (EFS p = 0.02; OS p = 0.01) in post‐NAC samples, independently from breast cancer subtypes. At multivariate analysis, only let‐7a‐5p was significantly associated with EFS (p = 0.009) and OS (p = 0.0008). Conclusion: Up‐regulation of the above miRNAs could represent biomarkers in breast cancer.