Identification of Stage-associated MicroRNAs in Lung Adenocarcinoma Based on Microarray Data

Background: Lung adenocarcinoma (LUAD) is the most aggressive and most frequently seen histological variant of lung cancers, comprising nearly 45% of the overall cases of lung carcinoma and its incidence has been increased significantly worldwide in the last several decades. However, there was limited available evidence with respect to the signalling pathways and miRNAs related to the LUAD.Methods: To identify the differentially-expressed miRNAs (DE-miRNAs) in different stages of LUAD, we performed a microarray on 514 LUAD and 54 normal tissues. At the mean time, the potentially targeted genes as well as the highly-enriched signaling pathways and the relevant protein–protein interaction (PPI) network were analyzed and constructed by using a series of bioinformatic methods. Moreover, the identified DE-miRNAs in different stages of the LUAD were verified by using the TCGA dataset.Results : Overall 41 down-regulated -and 82 up-regulated DE-miRNAs were identified, of which 1,716 potential targeted genes were selected. Moreover, the enriched pathways of the above genes were screened by using the GO term and KEGG pathway analyses, including the AMPK signalling pathway, FoxO signalling pathway, MAPK signalling pathway, PI3K-Akt signalling pathway and hippo signalling pathway.Conclusions: Our study could provide additional understanding of the underlying molecular events and increase the precision of prognostic prediction.