The result presented that KLF2 expression is significantly down-regulated in multiple solid cancers (Fig. 1A), such as breast invasive carcinoma (BRCA), colon adenocarcinoma (COAD), kidney renal papillary cell carcinoma (KIRP), lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), rectum adenocarcinoma (READ) and so on. The gene discussed is KLF2; the disease is lung adenocarcinoma.