Six2 overexpression inhibited epithelial marker E‐cadherin expression via stimulating its promoter methylation. A, B, E‐cadherin mRNA (A) and protein (B) levels were detected in NSCLC cells with or without six2 overexpression plus DNA methylation inhibitor (Decitabine) treatment or not. C, Genomic DNA from HCC cells with or without six2 overexpression was collected, and E‐cadherin promoter CpG methylation status was examined using EpiTech Methyl II PCR primer assay for the E‐cadherin promoter. D, The methylated level of E‐cadherin was measured in A549, NCI‐H1299 and BEAS‐2B cells. E, The correlation between six2 and E‐cadherin expression was analysed in NSCLC tissues. Data were presented as mean ± SD; *P < 0.05, **P < 0.01 vs A549 or H1299.