Identification of hub genes associated with prognosis of lung cancer via integrated bioinformatics and in vitro approach.

Lung cancer is a severe health problem that affects more men than women around the world. The goal of this study was to identify the biomarker hub genes for lung cancer in order to ascertain the biological pathway and protein- protein interaction networks. The microarray datasets GSE80796, GSE68571, GSE118370 and GSE43458 were retrieved from the GEO database and were analysed using GEO2R. STRING, Cytoscape, and cytoHubba were used to construct the PPI network and hub genes. GEPIA was used to obtain the overall survival and expression level in LUAD/LUSC and normal tissue. The MTT assay was used to examine antiproliferative activity. PI staining was used to determine the cell cycle arrest. qPCR was used to analyse gene expressions. The datasets revealed a total of 401 common DEGs, with 258 up-regulated genes and 143 down-regulated genes. Further, in-vitro study of gallic acid cytotoxic effect in human lung cancer cell line A549 indicated that gallic acid dramatically suppressed cell growth in A549 cells. Gallic acid also, significantly promoted programmed cell death by halting cells in the G0/G1 phase of the cell cycle. Taken together, our study indicated that gallic acid is a promising natural STAT1 inhibitor as it hindered lung cancer progression by inducing cell cycle arrest and apoptosis which can be employed to increase the therapeutic efficacy of existing lung cancer treatments and to improve overall patient survival.Communicated by Ramaswamy H. Sarma.