Abstract
BackgroundThe present study aims to investigate the preliminary mechanism underlying the peritoneal metastasis of gastric cancer cells.MethodsExosomes 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.ResultsFirstly, 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.ConclusionDecreased delivery of miR-486-5p via exosomes might be responsible for the peritoneal metastasis of gastric cancer cells by promoting epithelial-mesenchymal transition progress.
Highlights
Gastric cancer is commonest malignant tumor of the stomach with relatively high mortality rates globally [1]
Epithelial-mesenchymal transition (EMT) processing in the HMrSV5 cells was promoted more significantly by Exosomes from GC9811-P cells (PM-Exo) than Exosomes from GC9811 cells (Con-Exo) To evaluate the impact of Con-Exo and PM-Exo on the EMT processing in human peritoneal mesothelial cells, the morphology of treated HMrSV5 cells and the expression of EMT-related proteins were evaluated
We found that the morphology of HMrSV5 cells treated with Con-Exo and PM-Exo was changed to fusiform obviously, indicating that EMT was initiated
Summary
Gastric cancer is commonest malignant tumor of the stomach with relatively high mortality rates globally [1]. Peritoneal membrane is reported to be the commonest site of metastasis and recurrence in patients with gastric cancer [4]. The median survival rate of non-metastasic gastric cancer patients is 14 months, while the median survival rate of patients with peritoneal metastasis is around 4 months [5]. It is of great scientific and clinical significance to explore the pathological mechanism of peritoneal metastasis of gastric cancer for the diagnosis and treatment of advanced gastric cancer. The present study aims to investigate the preliminary mechanism underlying the peritoneal metastasis of gastric cancer cells
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
