On the other hand CXCR4, CLDN4, MMP9, OPN, TP53, CDKN2A, MUC16 and CD44v6 were upregulated (≥2 fold differently expressed) and CXCL12, CK7, CDH1, CTNNB1, HIF1A, VEGFA and TGFBR2 were downregulated (< 2 differently expressed) in lung cancer with liver metastasis as compared to primary tumor and Normal lung tissue. This evidence concerns the gene CLDN4 and lung cancer.