Breast cancer (BC), a heterogeneous group of diseases, is the most frequent type and the leading cause of cancer-related death among women worldwide. Tumor heterogeneity directly affects cancer progression and treatment, as can be evidenced by the diversity of the prognosis and treatment responses of the patients across the distinct intrinsic molecular subtypes. Triple-negative breast cancer (TNBC), which accounts for approximately 10-20 % of all diagnosed BC cases, is an aggressive BC subtype with a challenging prognosis. Current treatment options include systemic chemotherapy and/or target therapies based on PARP and PD-L1 inhibitors for eligible patients. MicroRNAs (miRNAs) have emerged as important regulatory non-coding RNAs (ncRNAs) in TNBC tumorigenesis. These molecules are present both at intracellular level, and as released into biofluids packaged into extracellular vesicles (EVs). Emerging evidence shows that EVs-associated miRNAs (EVs-miRNAs), transferred from parental cells to recipient cells, are key mediators of cell-to-cell communication. Considering their stability and abundance in several biofluids, these molecules may represent the epigenomic composition of their tumors of origin and contribute to mediate tumorigenesis similar to their intracellular counterparts. Researchers at the Pelé Pequeno Príncipe Research Institute provide the current knowledge on EVs-miRNAs in the TNBC subtype, focusing on their role in the regulation of mRNA targets involved in the tumor phenotypes and their clinical relevance as promising biomarkers in liquid biopsies.
Extracellular vesicles-associated miRNAs in triple-negative breast cancer
Berti FCB, Tofolo MV, Souza EN, Marchi R, Okano LM, Ruthes M, Rosolen D, Malheiros D, Fonseca AS, Cavalli LR. (2023) Extracellular vesicles-associated miRNAs in triple-negative breast cancer: From tumor biology to clinical relevance. Life Sci [Epub ahead of print]. [article]