MAPK/ERK信号通路在胃癌细胞来源的外来体诱导Jurkat T细胞凋亡中的作用

Role of MAPK/ERK signaling pathway in gastric cancer exosome-induced apoptosis of Jurkat T cells

目的:研究胃癌细胞来源的外来体对JurkatT细胞凋亡的影响,初步探讨MAPK/ERK通路在此过程中的作用.方法:采用离心超滤和蔗糖密度梯度超速离心的方法从胃癌SGC7901细胞的上清液中分离出胃癌细胞来源的外来体.透射电子显微镜下观察外来体形态,流式细胞仪PI染色检测细胞凋亡,Westernblot检测蛋白表达.结果:透射电子显微镜下观察胃癌SGC7901细胞来源的外来体具有特征性的盘状结构,由双层膜构成,他们的直径为30-100nm.外来体能以时间和剂量依赖性的方式诱导JurkatT细胞凋亡,在凋亡过程中伴有caspase-3,8的活化和p-ERK表达的下调.结论:胃癌细胞来源的外来体能诱导JurkatT细胞凋亡,其机制可能与抑制MAPK/ERK通路的活性有关.

AIM：To investigate the role of the mitogenactivated protein kinase （MAPK）/extracellular signal-regulated protein kinase （ERK） signaling pathway in gastric cancer exosome-induced apoptosis of Jurkat T cells.METHODS：Gastric cancer exosomes were isolated and purified by serial centrifugation and sucrose gradient ultracentrifugation.The morphology of gastric cancer exosomes was observed by electron microscopy.Cell apoptosis was determined by propidium iodide staining and ？ ow cytometry.The expression of caspase-3 and-8 and p-ERK was assayed by Western blot.RESULTS：Gastric cancer exosomes,ranging in diameter from 30 to 100 nm,had a characteristic saucer-like shape that was limited by a lipid bilayer.These exosomes induced Jurkat T cell apoptosis in a time-and dose-dependent manner.Activation of caspase-3 and-8 and downregulation of p-ERK expression were noted in exosome-induced apoptosis of Jurkat T cells.CONCLUSION：Gastric cancer exosomes induce apoptosis of Jurkat T cells possibly by inhibiting the MAPK/ERK pathway.