Extracellular vesicles in lung microenvironment and pathogenesis

• Extracellular vesicles (EVs) maintain lung physiological homeostasis.
• Various triggers can modify EV components and enhance EV secretion in the airway.
• EVs play important roles in inflammatory airway disease and in lung cancer pathogenesis.
• Mesenchymal stem cell-derived EVs may have therapeutic potential in lung damage.

Increasing attention is being paid to the role of extracellular vesicles (EVs) in various lung diseases. EVs are released by a variety of cells, including respiratory cells and immune cells, and they encapsulate various molecules, such as proteins and microRNAs, as modulators of intercellular communication. Cancer cell-derived EVs play crucial roles in promoting tumor progression and modifying their microenvironment. By contrast, noncancerous cell-derived EVs demonstrate protective functions against injury, such as tissue recovery and repair, to maintain physiological homeostasis. Airway cells in contact with harmful substances may alter their EV composition and modify the balanced reciprocal interactions with surrounding mesenchymal cells. We summarize the novel findings of EV function in various lung diseases, primarily chronic obstructive pulmonary disease (COPD) and lung cancer.