Triple negative breast cancer-derived extracellular-vesicles as naturally-occuring biomarkers and therapeutic delivery systems

Abstract

Background: In Ireland, breast cancer is the most commonly diagnosed cancer among women; and of the breast cancer subtypes, triple-negative breast cancers (TNBC) are the most aggressive. TNBCs account for 15%-20% of breast cancers, yet are responsible for a disproportionate number of breast cancer deaths. With no targeted treatments for TNBC, there is unmet clinical need for more effective targeted therapeutics. The relevance of extracellular vesicles (EVs) in cancer progression, diagnosis and therapeutics has been investigated, but not in TNBC. By transferring bioactive molecules, including proteins and nucleic acids, EVs have been shown to regulate hallmarks of cancer. Here, the potential of TNBC-derived EVs to mediate activities associated with metastasis is investigated; their nucleic acid contents analysed to determine their relevance as biomarkers; miRNA expression manipulated to assess therapeutic potential; and their clinical relevance as biomarkers evaluated using EVs from serum specimens of breast cancer patients and healthy volunteers.