RNA-Seq profiling of circular RNAs and potential function of hsa_circ_0002360 in human lung adenocarcinom.

CircRNAs have been identified play a key role in various different types of cancer. However, their role in lung adenocarcinoma remains unclear. In this study, we explored the specific circular transcriptome and characterized the circRNA expression profiles of five paired lung adenocarcinoma (LAC) tissues relative to adjacent normal tissues from LAC patients using next-generation sequencing (NGS). To illuminate circRNAs function, their gene targets were initially predicted before using, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses to further analyse the associated significant cell signalling pathways and functions. The potential interactions between circRNA-miRNA-mRNA were also investigated. Additionally, qRT-PCR assay, Western blot and Immunohistochemistry were performed to validate the differential expression of circRNA, microRNA and mRNA in the LAC group in comparison to the control group. Two-hundred-eighty-five dysregulated circular transcripts were found in LAC tissues, among which 102 and 183 were either up or down regulated, respectively. Our biological analysis suggested that the host genes of differentially expressed circRNAs targeted to cancer-related processes and mechanisms. The interaction maps of the circRNA-miRNA-target gene were constructed using Cytoscope. In further study, hsa_circ_0002360 was found to be the most significantly overexpressed circRNA in LAC tissues by interacting with miRNA and its corresponding mRNA. Our results showed that hsa_circ_0002360 was aberrantly and abundantly expressed and implicated in the development of LAC, suggesting a valuable therapeutic target for LAC treatment.