In the Supplementary Information two lists of genes that are differentially expressed can be found. The first list (S1) contains 25 genes and is the result of our meta—analysis approach, i.e. the genes are consistently differentially expressed in all six studies. The second list (S2) contains all the 102 genes that are differentially expressed after merging and batch effect removal. All genes in both lists can be considered as promising biomarkers for lung cancer.