Identification of a circRNA-miRNA-mRNA network to explore the effects of circRNAs on pathogenesis and treatment of spinal cord injury

Aims: Many studies have demonstrated that circRNAs are closely associated with human diseases. Nonetheless, the potential mechanism by which circRNAs impacts spinal cord injury (SCI) is not fully understood. The aim of this study was to explore the regulatory roles of circRNAs in SCI. Main methods: The sequencing data of circRNA, miRNA and mRNA were obtained from Gene Expression Omnibus (GEO) datasets. Candidates were identified to construct a circRNA-miRNA-mRNA network based on circRNA-miRNA interactions and miRNA-mRNA interactions. Protein-protein interactions (PPI) analysis was performed to determine hub genes, and a connectivity map (CMap) analysis was applied to determine potential therapeutic targets for SCI. Key findings: A total of 1656 differentially expressed circRNAs (DEcircRNAs), 71 differentially expressed miRNAs (DEmiRNAs) and 2782 differentially expressed mRNAs (DEmRNAs) were identified. We integrated four overlapped circRNAs, six miRNAs and 101 target mRNAs into a circRNA-miRNA-mRNA network. We next identified two hub genes (DDIT4, EZR) based on the PPI network and identified five circRNA-miRNA-hub gene regulatory axes. In addition, we discovered three chemicals (tanespimycin, fulvestrant, carbamazepine) as potential treatment options for SCI. Significance: Our study suggests a regulatory role for circRNAs in the pathogenesis and treatment of SCI from the view of a competitive endogenous RNA (ceRNA) network.