Extracellular vesicles (EVs), including microparticles and exosomes, have emerged as potential tools for tumor targeting delivery during the past years. Recently, mass of strategies are applied to assist EVs to accumulate and penetrate into deep tumor sites. In this review, EVs from different cells with unique innate characters and engineered approaches (e.g. chemical engineering, genetical engineering and biomimetic engineering) as drug delivery systems to enhance tumor accumulation and penetration are summarized. Meanwhile, efficient biological function modulation (e.g. extracellular matrix degradation, mechanical property regulation and transcytosis) is introduced to facilitate tumor accumulation and penetration of EVs. Finally, the prospects and challenges on further clinical applications of EVs are discussed.

在过去几年中，包括微粒和外泌体在内的细胞外囊泡 (EV) 已成为肿瘤靶向递送的潜在工具。最近，应用了大量策略来帮助 EVs 积累和渗透到深部肿瘤部位。在这篇综述中，总结了来自具有独特先天特性和工程方法（例如化学工程、基因工程和仿生工程）的不同细胞的 EV 作为药物递送系统以增强肿瘤积累和渗透。同时，引入有效的生物功能调节（例如细胞外基质降解、机械性能调节和转胞吞作用）以促进EV的肿瘤积累和渗透。最后，讨论了 EV 进一步临床应用的前景和挑战。