Exosomes Derived from Irradiated Esophageal Carcinoma-Infiltrating T Cells Promote Metastasis by Inducing the Epithelial-Mesenchymal Transition in Esophageal Cancer Cells.

Exosomes are nanovesicles derived from tumor and normal cells that are detectable in human biological fluids, such as plasma, and cell culture supernatants. The function of exosome secretion from "normal" cells is unclear. Although numerous studies have investigated exosomes derived from hematopoietic cells, little is known regarding exosomes fromT cells, even though these cells play significant roles in innate and acquired immunity. A CCK-8 assay was used to examine the ability of exosomes to inhibit TE13 cell proliferation. In vitro invasion and wound healing assays were conducted to explore the effects of exosomes on TE13 cell migration and invasion. A Western blottinganalys is was performed to investigate the effects of exosomes on the expression of the EMT-related moleculesβ-catenin, NF-κB and snail. This study aimed to investigate the effects of exosomes from irradiated T cells on the human esophageal squamous cell carcinoma (ESCC) cell line TE13 and revealed that exosomes inhibit the proliferation but promote the metastasis of TE13 cells in a dose-and time-dependent manner. Furthermore, exosomes significantly increased the expression of β-catenin, NF-κB and snail in TE13 cells. The results of this study suggest an important role for T cell-derived exosomes in the progression of esophageal carcinoma: T cell-derived exosomes promote esophageal cancer metastasis, likely by promoting the EMT through the upregulation of β-catenin and the NF-κB/snail pathway. Moreover, this study supports the use of exosomes as a nearly perfect example of biomimetic nanovesicles that could be utilized in future therapeutic strategies against various diseases, including cancer.