Using Gene Expression Profiling Interactive Analysis (GEPIA)27, an interactive web server for analysing RNA sequencing expression data of tumours and normal samples from The Cancer Genome Atlas (TCGA) and The Genotype-Tissue Expression (GTEx) database (https://gtexportal.org/home/), we found that a broad range of cancer tissues, including lung adenocarcinoma and lung squamous cell carcinoma, express higher levels of ALKBH4 mRNA than each corresponding normal tissue (Supplementary Fig. S3A). This evidence concerns the gene ALKBH4 and squamous cell lung carcinoma.