Purpose
Lung adenocarcinoma (LUAD) is one of the main types of lung cancer, the low rates for early diagnosis and a bad prognosis for advanced stage lead to a higher mortality rate. Therefore, it is of great significance to identify the related genes that promote its development.
Patients and methods
512 LUADs from The Cancer Genome Atlas were used to performed differentially expressed gene (DEG) analysis and short-term time-series expression miner to identify the LUAD-development characteristic gene sets. Survival analysis was applied to identified LUAD-unfavorable gene set and LUAD-favorable gene set. Gene set variation analysis (GSVA) was performed to score individual samples against the two gene sets. ROC curve analysis, univariate and multivariate cox regression analysis were used to evaluate the diagnostic and prognostic value of the two GSVA score systems. Two independent data sets from GEO were used for verifying the results. Functional enrichment analysis was used to explore the potential biological functions of LUAD-unfavorable gene set.
Results
With the development of LUAD, 185 DEGs were gradually up-graduated, including 84 genes associated with survival and classed as LUAD-unfavorable gene set; 237 DEGs were gradually down-graduated, including 39 genes associated with survival and classed as LUAD-favorable gene set. ROC curve analysis and univariate/multivariate Cox proportional hazards analyses indicated both of LUAD-unfavorable GSVA score and LUAD-favorable GSVA score were biomarkers for diagnosing LUAD and independent biomarkers for predicting prognosis. The LUAD-unfavorable genes were involved in multiple cancer-related pathways, such as p53 signaling pathway and cell cycle.
Conclusion
We identified and validated two LUAD-development characteristic gene sets that not only have diagnostic value but also prognostic value. It may provide new insight for further research on LUAD.