Identification of a circRNA-mediated immune-related ceRNA network and circRNAs as diagnostic biomarkers in acute ischemic stroke.

Abstract

Background: Research has demonstrated that circular RNAs (circRNAs) play important roles in acute ischemic stroke (AIS). However, the functions of circRNA-mediated competitive endogenous RNA (ceRNA) in AIS-related immunological inflammation are not well understood. In our study, we aimed to construct a circRNA-mediated immune-related ceRNA network and identify diagnostic circRNAs for AIS.

Methods: R software was used to analyze the microarray data obtained from the GEO database. The bioinformatics database was then used to develop the circRNA-mediated ceRNA network. A topological property study of the ceRNA network was performed to identify new circRNAs. Subsequently, we validated the potential circRNAs in both mice middle cerebral artery occlusion (MCAO) model and clinical samples obtained from our center with quantitative real-time polymerase chain reaction (qRT-PCR).

Results: An AIS immune-related ceRNA (AISIRC) network was constructed, comprising immune-related genes (IRGs), circRNAs, and miRNAs. A subnetwork was then extracted from the AISIRC network and we identified seven circRNAs associated with immune response. The qRT-PCR assays were conducted to validate the circRNAs candidate using blood samples from MCAO mice. The results demonstrated that circulating circOXCT1 and circSLC8A1 were significantly up-regulated in AIS patients. Receiver-operating characteristic (ROC) curve analyses and logistic regression demonstrated the perfect predictive and discriminative features of these two circRNAs biomarkers in AIS. Longitudinal analysis of circRNA expression after AIS indicated the promising potential of circSLC8A1 for monitoring AIS progression and dynamics.

Conclusion: We successfully constructed circRNA-mediated immune-related ceRNA network and identified two circulating circRNAs (circOXCT1 and circSLC8A1), which showed high diagnostic sensitivity for AIS.