Fig. 1

The workflow for identification of candidate biomarkers for early diagnosis of lung adenocarcinoma (LUAD). The workflow contains two parts: bioinformatics analysis and clinical validation. The bioinformatics analysis contains upregulated differentially expressed genes (DEGs) screening and genes encoding secreted proteins predicted by the majority decision-based method. The expressions of the identified secreted proteins are validated using the TCGA and CPTAC databases. The clinical validation was carried out using the plasma samples of 26 early-stage LUAD patients and 11 healthy donors