Advances in Research on the circRNA-miRNA-mRNA regulatory network in lung adenocarcinoma by analysis of microarray data

Abstract

Background: The present researches indicate that circular RNAs (circRNAs) play pivotal roles in the generation and development of human cancers. However, function of circRNAs in lung adenocarcinoma is still unknown. Herein, we focused our study on the regulation mechanism of circRNAs in lung adenocarcinoma (LUAC)Methods: CircRNAs-related data can be downloaded from Gene Expression Omnibus(GEO) microarray databases. Relevant expression data of miRNAs and mRNAs were obtained from The Cancer Genome Atlas (TCGA) databases. The differentially expressed circRNAs (DEcircRNAs) were obtained by the robust rank aggregation method, and constructed a ceRNA network with circRNA-miRNA pairs and miRNA-mRNA pairs. The function and pathway enrichment of different genes were analyzed, and the protein-protein interaction (PPI) was predicted by String software, and the subnetwork management module was constructed by MCODE plugin. The differentially expressed mRNAs (DEmRNAs) were used to establish survival analysis by R software.Results: A total of 19 up-regulated circRNAs, 45 down-regulated circRNAs, 98 up-regulated miRNAs, 18 down-regulated miRNAs, 2002 up-regulated mRNAs, and 553 down-regulated mRNAs were obtained in lung adenocarcinoma. The circRNA-miRNA-mRNA network was constructed by six circRNAs (hsa_circ_0003528, hsa_circ_0004315, hsa_circ_0005699, hsa_circ_0002588, hsa_circ_0005777, hsa_circ_0027033), 19 miRNAs and 33 mRNAs. GO and KEGG pathway analysis indicated that DEmRNAs might be related to the progression of LUAC. The PPI network was constructed and four hub genes (CEP55, CHEK1, CDC25A, KIF23) were obtained from the network, and four hub genes were found to be associated with the same miRNA and circRNA, including hsa_circ_0004315/hsa-miR-195/CEP55, CHEK1, CDC25A, KIF23. Three hub genes (CEP55, CHEK1, KIF23) were significantly associated with LUAC survival and prognosis, and the overall survival rate of lung adenocarcinoma was decreased in high-expression genes compared with low-expression genes.Conclusion: Our finding indicated that circRNA-miRNA- mRNA axis paly key role in the pathogenesis of lung adenocarcinoma, and some circRNAs could be considered as a biomarker and target for the diagnosis and therapy of LUAC patients.