Repression of DOK7 mediated by DNMT3A promotes the proliferation and invasion of KYSE410 and TE-12 ESCC cells.

Increasing evidence shows that aberrant epigenetic regulation of tumor suppressor genes is a contributing factor to their altered expression in esophageal squamous cell carcinoma (ESCC). In the current study, we investigate the role of DOK7 in ESCC cells. We found that enforced expression of DOK7 inhibited the proliferation and invasion of ESCC cells. We also found that treatment of ESCC cells with the DNA methylation inhibitor, 5-aza-2-deoxycytidine (5-azadC), induced the demethylation of DOK7 in promoter and DOK7 expression. Moreover, silencing DNMT3A decreased methylation of DOK7 and increased DOK7 expression, followed by repressing the proliferation and invasion of ESCC cells. Collectively, our data indicated that silencing DNMT3A inhibits proliferation and invasion in ESCC cells by inducing demethylation of DOK7.