Exosome, a membranous vesicle with biological activity, not only transmits active substances between cells but also transfers information between cells to participate in cell communication. Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells acquire migratory and invasive properties to become mesenchymal stem cells. EMT is essential for the development of a spectrum of diseases. Studies have shown that exosomes have dual effects on EMT to, on the one hand, promote EMT and tumor cell invasion and metastasis and accelerate angiogenesis and tumor growth; on the other hand, exosomes can suppress tumor cell invasion, inhibit fibrosis of the heart, liver and kidney, and improve myocardial infarction by inhibiting EMT. Exosomes modulate EMT-related signaling pathways by carrying EMT-related proteins or miRNA to exert their bi-directional regulatory effects.
外泌体是一种具有生物活性的膜性囊泡，既可在细胞间传递活性物质，还可通过调控细胞间的信息传递参与细胞活动。上皮-间质转化（EMT）是上皮细胞获得间充质细胞特性的过程，在众多疾病中发挥了重要作用。研究表明，外泌体在EMT的发生发展过程中具有双向作用。一方面，外泌体可促进细胞发生EMT，赋予肿瘤细胞侵袭和转移能力，促进血管新生和加快肿瘤生长；另一方面，外泌体亦可抑制EMT，发挥减弱肿瘤细胞侵袭能力，抑制心、肝、肾纤维化，改善心肌梗死等作用。外泌体可能是通过携带EMT相关蛋白或miRNA，调控EMT相关信号通路发挥双向调节作用。
Keywords: epithelial-mesenchymal transition; exosomes; fibrosis; tumor.