Decreased exosome-delivered miR-486-5p is responsible for the peritoneal metastasis of gastric cancer cells by promoting EMT progress

Xian-Ming Lin; Zhi-Jiang Wang; Yu-Xiao Lin; Hao Chen

doi:10.1186/s12957-021-02381-5

Decreased exosome-delivered miR-486-5p is responsible for the peritoneal metastasis of gastric cancer cells by promoting EMT progress

World J Surg Oncol. 2021 Oct 23;19(1):312. doi: 10.1186/s12957-021-02381-5.

Authors

Xian-Ming Lin¹, Zhi-Jiang Wang², Yu-Xiao Lin^{3

4}, Hao Chen⁵

Affiliations

¹ Department of General Surgery, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, People's Republic of China. zrlxm@zju.edu.cn.
² Department of General Surgery, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, People's Republic of China.
³ Next Generation Sequencing, DIAN Diagnostics Group Co., Ltd., Hangzhou, 310030, Zhejiang, People's Republic of China.
⁴ Next Generation Sequencing, Hangzhou Dian Huayin Biotechnology Co., Ltd., Hangzhou, 310030, Zhejiang, People's Republic of China.
⁵ Safety Evaluation Center, Zhejiang Academy of Medical Sciences, Hangzhou, 310007, Zhejiang, People's Republic of China.

Abstract

Background: The present study aims to investigate the preliminary mechanism underlying the peritoneal metastasis of gastric cancer cells.

Methods: Exosomes from GC9811 cells (Con-Exo) and from GC9811-P cells (PM-Exo) were extracted by ultracentrifugation, which were identified with transmission electron microscopy (TEM) and nanoparticle trafficking analysis, as well as the expression of CD9, CD63, and CD81 detected by Western blot assay. α-SMA expression was determined by immunofluorescence assay and Western blot assay. The levels of Snail1, E-cadherin, and Actin-related protein 3 (ACTR3) were evaluated by Western blot assay. MiRNA array was performed on exosomes to screen the differentially expressed miRNAs. The expressions of miRNAs, SMAD2, CDK4, and ACTR3 were determined by QRT-PCR. The delivery of miR-486-5p was confirmed by laser confocal detection.

Results: Firstly, TEM, nanoparticle trafficking analysis, and Western blot assays were used to confirm the successful extraction of Con-Exo and PM-Exo. The incubation of Con-Exo and PM-Exo could decrease E-cadherin expression and increase of α-SMA respectively in HMrSV5 cells, with the increased proportion of fusiform cells. More significant changes were observed in PM-Exo-treated HMrSV5 cells. Secondary, compared to Con-Exo, miR-486-5p and miR-132-3p were found downregulated, and miR-132-5p was found upregulated in PM-Exo. The transfection of miR-486-5p and miR-132-3p was observed to suppress EMT, and the transfection of miR-132-3p was observed to induce EMT. Laser confocal detection confirmed the delivery of miR-486-5p from gastric cancer cells to HMrSV5 cells through exosomes. Lastly, the expression of Mothers against decapentaplegic homolog 2 (SMAD2), cyclin-dependent kinase 4 (CDK4), and ACTR3 was found to be downregulated via miR-486-5p.

Conclusion: Decreased delivery of miR-486-5p via exosomes might be responsible for the peritoneal metastasis of gastric cancer cells by promoting epithelial-mesenchymal transition progress.

Keywords: Epithelial-mesenchymal transition; Exosome; Gastric cancer; miR-486-5p.

MeSH terms

Exosomes*
Humans
MicroRNAs* / genetics
Peritoneal Neoplasms*
Prognosis
Stomach Neoplasms* / genetics

Substances

MIRN486 microRNA, human
MicroRNAs