Analysis of differentially expressed circular RNAs for the identification of a coexpression RNA network and signature in colorectal cancer.

Circular RNAs (circRNAs) play an important regulatory role in tumorigenesis. The aim of the present study was to analyze the circRNA expression network and elucidate its potential implications in colorectal cancer (CRC). The circRNA expression profile was analyzed in CRC tissues by RNA sequencing, and the functions of differentially expressed genes were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The circRNA network was predicted with bioinformatics. On the basis of the results, we identified 23 differentially expressed circRNAs in CRC; GO and KEGG analyses demonstrated that the changes in circRNAs were mainly associated with regulation of biological and metabolic processes through binding to other molecules. In addition, based on the predicted coexpression network, we identified a hub circRNA, hsa_circ_0009022. Subsequently, the results of sequencing were confirmed by reverse transcription-quantitative polymerase chain reaction, and hsa_circ_0000826 was found to be downregulated in CRC. Taken together, these findings indicate a set of differentially expressed circRNAs that may serve as a candidate diagnostic biomarker and a promising therapeutic target in CRC.