MicroRNA Extracellular Vesicle Stowaways in Cell-Cell Communication and Organ Crosstalk.

Extracellular vesicles (EVs) function as mediators of cell-cell communication1 and organ crosstalk,2 but a complete understanding of the mechanistic roles this critical communication process plays in cardiovascular and associated diseases is lacking. In normal conditions, EV crosstalk is important for proper cell and organ function, but in diseased conditions EV cargos can be altered in a way that promotes disease pathology. Multiple cargos have been observed in EVs, including RNAs, such as microRNA, DNA, proteins, and lipids, which can be encased within EVs or associated with EV membranes. Given this critical function, identifying the communication roles of EVs in normal physiology and diseasedriving mechanisms holds great therapeutic promise. In this issue of Arteriosclerosis, Thrombosis, and Vascular Biology, Chang et al3 propose EV transport as a major pathway in which miR-92a is transported from endothelial cells to macrophages that, in turn, contributes to the development of atherosclerosis. This study identifies a key mechanism of how miR-92a cell-cell communication occurs in atherosclerotic vasculature and raises the potential of EV-associated miR-92a as a disease biomarker and therapeutic target.