Differential expression and bioinformatics analysis of exosome circRNAs in pancreatic ductal adenocarcinoma

Jiayi Wang; Xing Wu; Jiahao Xu; Yangjie Liao; Minzi Deng; Xiaoyan Wang; Jingbo Li

doi:10.1016/j.tranon.2023.101686

Differential expression and bioinformatics analysis of exosome circRNAs in pancreatic ductal adenocarcinoma

Transl Oncol. 2023 Jul:33:101686. doi: 10.1016/j.tranon.2023.101686. Epub 2023 May 12.

Authors

Jiayi Wang¹, Xing Wu¹, Jiahao Xu¹, Yangjie Liao¹, Minzi Deng¹, Xiaoyan Wang¹, Jingbo Li²

Affiliations

¹ Department of Gastroenterology, The Third Xiangya Hospital, Central South University, Changsha 41000, China.
² Department of Gastroenterology, The Third Xiangya Hospital, Central South University, Changsha 41000, China. Electronic address: jingboli@csu.edu.cn.

Abstract

Background: Pancreatic ductal adenocarcinoma (PDAC) is a fatal malignant tumor with an unfavorable prognosis. Increasing evidence indicated circRNAs were associated with the pathogenesis and progression of tumors, but data on the expression of serum exosomal circRNAs in PDAC are scarce. This study attempted to explore the prognostic value and function of serum exosomes in PDAC patients.

Methods: Microarray-based circRNA expression was determined in PDAC and paired with normal serum samples, and the intersection of differentially expressed circRNAs (DECs) in serum exosomal samples and GSE79634 tissue samples was conducted. A specific CircRNA database was applied to investigate DECs binding miRNAs. Target genes were predicted using the R package multiMiR. Cox regression analyses were applied for constructing a prognostic model. The immunological characteristics analysis was carried out through the TIMER, QUANTISEQ, XCELL, EPIC, and ssGSEA algorithms.

Results: 15 DECs were finally identified, and a circRNA-miRNA-mRNA network was established. A prognostic risk model was developed to categorize patients according to the risk scores. Furthermore, the association between risk score and immune checkpoint genes including CD80, TNFSF9, CD276, CD274, LGALS9, and CD44 were significantly elevated in the high-risk group, while ICOSLG and ADORA2A were upregulated in the low-risk group.

Conclusions: Our results may provide new clues for the prognosis and treatment of PDAC.

Keywords: Bioinformatics; Circular RNA; Exosome; Pancreatic ductal adenocarcinoma.