Evaluation of the Diagnostic Potential of a Plasma Exosomal miRNAs Panel for Gastric Cancer

PURPOSE: Gastric cancer (GC) is often difficult to diagnose early in the disease and remains one of the most frequently occurring malignancies. This investigation looks at the diagnostic potential of a specific plasma exosomal miRNAs panel for GC. METHODS: This study analyzed 216 individual peripheral blood samples. 2 GEO datasets were analyzed and two miRNAs were selected - plasma exosomal miR-195-5p and miR-211-5p. Quantitative reverse-transcriptase PCR (qRT–PCR) was used to assess relative expressions and receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic efficiency of miR-195-5p and miR-211-5p panel. The Kaplan-Meier method was used to assess the prognostic value of plasma exosomal miR-195-5p and miR-211-5p. RESULTS: GC patients possessed notably raised plasma levels of exosomal miR-195-5p and miR-211-5p. The area under ROC curves (AUCs) of miR-195-5p, miR-211-5p were 0.745, 0.798 in the screening phase and 0.762, 0.798 in the training stage respectively. GC was able to be diagnosed more accurately when both miRNAs were interpreted together (AUC=0.820 in the validation stage). Poorer prognosis was observed in GC patients who had plasma exosomal miR-195-5p and miR-211-5p of higher levels. In vitro experiments also confirmed that miR-195-5p and miR-211-5p is able to be transmitted between cells, and works to enhance tumor invasion, migration and proliferation while inhibiting cell apoptosis. CONCLUSION: Plasma exosomal miR-195-5p and miR-211-5p may become potential biomarkers for GC diagnosis, and may be useful in predicting tumor phenotype.