小细胞外囊泡（外泌体）是肿瘤微环境的重要组成部分。它们是来自几乎所有细胞类型的小膜结合囊泡，在细胞间通讯中发挥重要作用。外泌体传输从亲本细胞获得的生物分子，例如蛋白质、脂质和核酸，并参与癌症的发展。 MicroRNA（miRNA）是外泌体中最丰富的内容物，被选择性地包装到外泌体中以发挥其生物学功能。最近的研究表明，外泌体递送的 miRNA 在肝细胞癌 (HCC) 的肿瘤发生、进展和耐药性中发挥着至关重要的作用。此外，外泌体在HCC患者的诊断、治疗和预后方面具有巨大的工业前景。该综述总结了 HCC 中不同细胞来源的外泌体 miRNA 的组成和功能，并强调了肿瘤微环境中基质细胞和免疫细胞的外泌体 miRNA 与 HCC 进展之间的关联。最后，我们描述了间充质干细胞来源的外泌体 miRNA 在治疗 HCC 中的潜在应用。©作者 2023。百世登出版集团有限公司出版。保留所有权利。

Small extracellular vesicles (exosomes) are important components of the tumor microenvironment. They are small membrane-bound vesicles derived from almost all cell types and play an important role in intercellular communication. Exosomes transmit biological molecules obtained from parent cells, such as proteins, lipids, and nucleic acids, and are involved in cancer development. MicroRNAs (miRNAs), the most abundant contents in exosomes, are selectively packaged into exosomes to carry out their biological functions. Recent studies have revealed that exosome-delivered miRNAs play crucial roles in the tumorigenesis, progression, and drug resistance of hepatocellular carcinoma (HCC). In addition, exosomes have great industrial prospects in the diagnosis, treatment, and prognosis of patients with HCC. This review summarized the composition and function of exosomal miRNAs of different cell origins in HCC and highlighted the association between exosomal miRNAs from stromal cells and immune cells in the tumor microenvironment and the progression of HCC. Finally, we described the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of HCC.©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.