CDH1 and cancer: In contrast, normal lung epithelial BEAS‐2B cells expressing a low level of six2 and a high level of E‐cadherin had correspondingly a low level of E‐cadherin promoter methylation, and these effects were consistent with the previous work showing that the decrease of E‐cadherin expression is resulted by DNA methylation in human cancers.16 Importantly, we found that six2 expression was negatively correlated with E‐cadherin expression in NSCLC tissues, and six2 promoted E‐cadherin methylation.