Background

Breast cancer is a common female malignancy. In recent years, the incidence of breast cancer has increased and has become much younger. Studies have shown that platelet-derived exosomes play an important role in the progression of cancer.

Objective

In this study, we investigated the effect of platelet-derived exosomes on the epithelial–mesenchymal transition (EMT), migration, and invasion of breast cancer cells. Activated and unactivated platelet-derived exosomes were extracted by ultracentrifugation. The morphology of platelet exosomes was observed and identified by transmission electron microscopy and western blotting. After MCF7 cells are treated with platelet or exosomes, the mRNA and protein levels of EMT-related genes were detected by RT-PCR and western blotting, respectively, and the migration and invasion abilities of MCF7 cells were also observed by transwell.

Results

We observed some exosomes-like structures derived from activated platelets by transmission electron microscopy. The level of transforming growth factor-β in activated platelet-derived exosomes was higher than that in unactivated platelet-derived exosomes. After activated platelet or activated platelet-derived exosomes were co-cultured with MCF7 cells, the expression of Snai1, N-cadherin, Vimentin and Fibronectin in activated platelets and breast cancer cells was significantly increased, while the expression of E-cadherin was significantly decreased. Activated platelets and activated platelet-derived exosomes significantly promoted the migration and invasiveness of MCF7 cells. These findings revealed that activated platelet or activated platelet-derived exosome enhances migration and invasion by promoting EMT in MCF cells.

Conclusion

In conclusion, platelet-derived exosomes initiate EMT and promote the migration and invasiveness of MCF7 cells.

中文翻译：

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血小板衍生的外泌体促进 MCF7 细胞的上皮间质转化

背景

乳腺癌是一种常见的女性恶性肿瘤。近年来，乳腺癌的发病率有所增加，并且变得更加年轻化。研究表明，血小板衍生的外泌体在癌症的进展中起着重要作用。

客观的

在这项研究中，我们研究了血小板衍生的外泌体对乳腺癌细胞上皮间质转化（EMT）、迁移和侵袭的影响。通过超速离心提取活化和未活化的血小板衍生的外泌体。通过透射电子显微镜和蛋白质印迹观察和鉴定血小板外泌体的形态。用血小板或外泌体处理MCF7细胞后，分别通过RT-PCR和western blotting检测EMT相关基因的mRNA和蛋白水平，transwell还观察MCF7细胞的迁移和侵袭能力。

结果

我们通过透射电子显微镜观察到一些源自活化血小板的外泌体样结构。活化的血小板衍生的外泌体中转化生长因子-β的水平高于未活化的血小板衍生的外泌体。活化血小板或活化血小板衍生的外泌体与MCF7细胞共培养后，活化血小板和乳腺癌细胞中Snai1、N-cadherin、Vimentin和Fibronectin的表达显着增加，而E-cadherin的表达显着降低. 活化的血小板和活化的血小板衍生外泌体显着促进了 MCF7 细胞的迁移和侵袭。这些发现表明，活化的血小板或活化的血小板衍生的外泌体通过促进 MCF 细胞中的 EMT 来增强迁移和侵袭。

结论

总之，血小板衍生的外泌体启动 EMT 并促进 MCF7 细胞的迁移和侵袭。