Screening potential biomarkers for colorectal cancer based on circular RNA chips

The aim of the present study was to screen colorectal cancer (CRC) tissue and adjacent tissue for differences in circular RNA (circRNA) expression, to analyze the related miRNAs and messenger RNAs (mRNAs), and to investigate the circRNA expression in CRC and its function. The circRNA expression profile was generated using CapitalBio microarray technology. The differentially expressed circRNAs were identified with GeneSpring 12.5 software. Subsequently, the related mRNAs of the differentially expressed circRNAs were annotated with the molecule annotation system (MAS) 3.0, and the diseases, pathways and functional enrichment analysis of these mRNAs were performed using the KEGG orthology-based annotation system (KOBAS) 3.0. In addition, the target miRNAs of differentially expressed circRNAs were screened using the miRanda algorithm. The circRNA/miRNA network was constructed for the top 8 most significant differentially expressed circRNAs with Cytoscape software 3.4.0. A total of 10,245 differentially expressed circRNAs were identified, including 6,264 upregulated ones, and 3,981 downregulated ones. The related mRNAs were enriched in 462 KEGG diseases, 411 FunDO, 669 NHGRI GWAS catalog, and 845 OMIM; and 1,334 Reactomes, 281 KEGG pathways, 117 PANTHER and 193 BioCyc; and 11,606 Gene Ontology (GO) terms. A total of 133 circRNA/miRNA pairs were involved in the circRNA/miRNA network. hsa_circ_0126897_CBC1 may be a potential biomarker for CRC, and the cell cycle was closely associated with the occurrence and development of CRC.