Biomarkers associated with metastasis and prognosis of lung adenocarcinoma based on microarray data

We attempted to discover the biomarker associated with metastasis and prognosis of lung adenocarcinoma. The mRNA/lncRNA expression profiles (GSE101836) were downloaded from the publicly available database, which included three highly metastatic and three weakly metastatic samples. The differentially expressed genes and lncRNAs were analyzed and survival analysis were performed based on the TCGA database. The prognosis-associated PPI network and mRNA-lncRNA coexpression network were constructed followed by the function and pathway enrichment analysis. The expression levels of key genes were validated in other datasets. Difference in gender was analyzed. Total 256 differentially expressed genes and 2 lncRNAs were found to be closely related with prognosis. PPI network was constructed with 222 nodes and 1464 edges. Two modules were divided from PPI network. Genes in module A were significantly enriched in cell cycle checkpoint, chromosome segregation, and mitotic cell cycle checkpoint. The module B was closely related with pyridine nucleotide metabolic process, nicotinamide nucleotide metabolic process and carbon metabolism. Coexpression network revealed lncRNA H19 and lncRNA SNHG12 were significant nodes. SNHG12 was closely related with GO:0006260~DNA replication, GO:0055114~oxidation-reduction process and hsa00010: Glycolysis/Gluconeogenesis. H19 was enriched in GO:0006555~methionine metabolic process, and GO:0046655~folic acid metabolic process. The expression levels of TTK and CCNB1 were confirmed in other datasets. The expression of TTK and CCNB1 was significantly higher in the male group than in the female group. TTK, CCNB1 and lncRNA SNHG12 may be the biomarker associated with metastasis and prognosis of lung adenocarcinoma.