The analysis of DNA methylation at the level of CpG island promoter regions allowed to identify three groups of lung adenocarcinomas according to the level of methylation: (i) a CIMP-H (high) group characterized by the hypomethylation of several genes (CDKN2A, GATA2, GATA4, GATA5, HOXA9, HOXD13, SOX17, WIF1), overexpression of WNT pathway genes and MYC overexpression; (ii) CIMP-I (intermediate); (iii) CIMP-L (low). Here, CDKN2A is linked to lung adenocarcinoma.