Comprehensive Analysis of circRNA-miRNA-mRNA in Oral Squamous Cell Carcinoma

The aim of the present study was to explore expression profiles of circular RNAs (circRNAs) and potential molecular mechanisms in oral squamous cell carcinoma (OSCC).In this study, high-throughput microarray was used to detect the expression profiles of circRNAs in OSCC. Reverse transcription quantitative PCR (RT-qPCR) was used to quantify the expression of dysregulated circRNAs in microarray. The validated microRNAs sponged by circRNAs and targeted mRNA were collected from literatures and miRTarBase database. and Gene Ontologypathways were analyzed on DAVID platform. Furthermore, network of circRNA-miRNA-mRNA and protein-protein interaction were constructed by Cytoscape 6.0 software.The results revealed that 1540 circRNAs were differentially expressed in 4 paired OSCC tissues and adjacent tissues significantly. Among them, 6 abundant circRNAs which have been reported in literatures were identified through RT-qPCR. According to the hypothesis of competing endogenous RNAs, 14 miRNAs sponged by the validated circRNAs and 62 downstream target protein coding genes were identified. Upon Gene Ontologyanalysis, 62 target genes were found to play roles in positively regulation of cell migration, cell division, angiogenesis and response to hypoxia. For Kyoto Encyclopedia of Genes and Genomes pathways, target genes were found to be involved in oncogenic signaling pathways (hsa05200), PI3K-Akt signaling pathway (hsa04151), focal adhesion (hsa04510), microRNAs in cancer (hsa05206), ECM-receptor interaction (hsa04512). These results suggested that circRNAs may participate in the tumorigenesis and development of OSCC via sponging miRNAs.This study indicated that circRNA may play vital role in tumorigenesis and metastasis in OSCC.