Microarray expression profile and bioinformatic analyses of circular RNA in human esophageal carcinoma

Abstract

Background : Recent studies indicate that noncoding circular RNAs (circRNAs) are involved in the development of esophageal carcinoma. This study aimed to identify circRNAs that are differentially expressed in esophageal carcinoma (EC), which may provide potential biomarkers and therapeutic targets for EC and improve the understanding of its tumorigenesis mechanism. Methods : Ten samples of esophageal carcinoma tissues were sent for circRNA microarray detection. Then the data was subjected to bioimformatic analysis (including circRNA-microRNA (miRNA) coexpression network, Spearman’s correlation test and cancer-related circRNA-miRNA axis analyses). The gene expressions of key circRNAs were detected by real-time- PCR. Results: A total of 102 upregulated and 67 significantly downregulated circRNAs were identified in EC tumors compared to adjacent normal tissue by microarray analysis. One upregulated circRNA (hsa_circRNA_401955) showed the most correlation and was thus regarded as the hub gene by the Spearman correlation test. KEGG pathway enrichment analyses showed that four primary pathways (mRNA surveillance, cytoskeletn actin regulation, spliceosome and the NOD-like receptor signaling pathway) were predicted in the five connected miRNA response elements (MREs) of hub circRNA’ s. Furthermore, cancer-related circRNA-miRNA axis analyses revealed that hsa_circRNA_100375 and its four connected MREs contributed to a cancer-related pathway. The expressions of hsa_circRNA_100375 and hsa_circRNA_401955 were increased significantly in the tumor tissues according to q-PCR. Conclusion: CircRNA dysregulation was involved in the tumorigenesis of EC. The key circRNAs of hsa_circRNA_401955 and hsa_circRNA_100375 may serve as potential biomarkers and therapeutic targets for EC.