Exosomes Serve as Nanoparticles to Deliver Anti-miR-214 to Reverse Chemoresistance to Cisplatin in Gastric Cancer.

Chemoresistance is one of the causes of adverse effects in gastric cancer, including a poor response to cisplatin (DDP). Exosomes loaded with microRNA (miRNA), mRNA, and other non-coding RNAs could regulate drug resistance. Exo-anti-214 was extracted and verified. A Cell Counting Kit-8 (CCK-8) cell viability assay, flow cytometry, and transwell and immunofluorescence assays were performed to determine whether exo-anti-214 could sensitize cells to DDP in vitro. A combination of intravenously injected exo-anti-214 and intraperitoneal DDP was utilized in vivo. Additionally, potential targets of miR-214 were screened by mass spectrometry (MS) and confirmed via western blotting (WB). The levels of miR-214 in the human immortalized gastric epithelial cell line ges-1 and the human gastric adenocarcinoma cell lines SGC7901 and SGC7901/DDP gradually increased. Exo-anti-214 could fuse with cells and regulate potential targets, reducing cell viability, suppressing migration, and promoting apoptosis in vitro. Caudally injected exo-anti-214 was applied to reverse chemoresistance and repress tumor growth in vivo due to the downregulation of miR-214 and overexpression of possible target proteins in tumors. Exo-anti-214 could reverse the resistance to DDP in gastric cancer, which might serve as a potential alternative for the treatment of cisplatin-refractory gastric cancer in the future.