Profiling and functional analysis of exosomal circRNAs from EBV-associated gastric carcinoma CSCs

Recent studies have found that Epstein-Barr virus (EBV) encodes circular RNAs (ebv-circRNAs) that are involved in tumorigenesis process in EBV-associated gastric carcinoma (EBVaGC). Since little is known whether circRNAs can be enriched into exosomes and their functions in EBVaGC, the aim of our work was to investigate the expression pattern of circRNAs in exosomes derived from EBVaGC cancer stem cells (CSCs). Here, we found two circRNAs, ebv-circLMP2A and hsa-circRNF13 were enriched in EBVaGC CSCs derived exosomes and positively associated with EBVaGC patients with metastasis. Bioinformatics analysis predicted that miR-5683 is the most likely potential target for hsa-circRNF13, and lower miR-5683 expression was positively correlated with microvessel density and Ki67 expression in clinical samples of EBVaGC. Cytology experiments showed that EBVaGC CSCs derived exosomes significantly promoted the invasive growth of EBVaGC cells. Our findings suggest that exosomal circRNAs could be a promising diagnostic and therapeutic target for EBVaGC.