Signature of miRNA expression in triple-negative breast cancer patients undergoing neoadjuvant therapy

Abstract

Breast cancer is the most common malignancy and the leading cause of cancer-related deaths among women. Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that accounts for 10-15% of all cases. Due to the loss of three certain receptors in TNBC cells, treatment options are limited, and the disease is associated with a poor prognosis. MicroRNAs (miRNAs) are small non-coding RNA molecules whose dysregulation can alter the expression of specific genes, affecting cancer pathogenesis. This study aims to provide insights into the role of selected miRNAs in TNBC progression. Bioinformatic case study analysis of the cancer genome atlas (TCGA) datasets revealed 195 differentially expressed miRNAs targeting 57 genes linked to the platinum drug resistance pathway. Analysis of patient survival data showed 13 of those to be directly related to patient survival rate. Subsequently, we selected four different miRNAs for quantitative reverse transcription PCR verification in whole blood and formalin-fixed paraffin-embedded (FFPE) tissue specimens from patients with TNBC undergoing neoadjuvant chemotherapy. Finally, statistical analysis was performed to compare miRNA expression levels across the different specimens.