Extracellular Vesicles as Natural Nanocarriers in Cancer Therapy: Prospects and Translational Barriers

Extracellular vesicles (EVs) are membrane-bound particles released by cells and involved in intercellular communication. Small EV preparations are being investigated as carriers for anticancer drugs, RNA therapeutics and immune-modulating molecules because their membranes can protect cargo and interact with recipient cells. However, these features do not automatically confer tumour specificity, prolonged circulation or low immunogenicity. EV preparations vary with their cellular source, isolation method and handling, and commonly used methods may co-isolate non-vesicular particles. Preclinical studies have demonstrated proof of concept for targeted RNA delivery, including approaches directed at oncogenic KRAS in pancreatic cancer models, and early clinical studies have assessed dendritic-cell-derived EV vaccines. Yet clinical evidence remains limited, and no EV-based cancer therapeutic is established as an approved standard treatment. This article outlines the biology of EVs, their potential applications in drug delivery, immunotherapy and liquid biopsy, and the scientific and manufacturing barriers that must be addressed before routine clinical use.