Objective:To investigate the correlation between E-cadherin and miR-148a,and explore the underlying mechanism of miR-148a regulating E-cadherin expression in gastric cancer. Methods:The mRNA levels of E-cadherin and miR-148a were detected by qRT-PCR,and protein expression of E-cadherin was assayed by Western blot;A correlation between E-cadherin mRNA levels and that of miR-148a in gastric cancer was investigated by Pearson correlation analyses;The relationship between aberrant methylation and E-cadherin expression was evaluated by treatment of gastric cancer cells with demethylation drug;The regulatory mechanism of miR-148a modulating E-cadherin was analyzed by transfection of gastric cancer cells with miR-148a mimics or DNA methyltransferase 1 (DNMT1) siRNA. Results:The mRNA and protein levels of E-cadherin were significantly downregulated in gastric cancer tissues compared with corresponding normal tissues,and were positively correlated with miR-148a expression. After treatment of MGC-803 and SGC-7901 cells with 5-aza-dC, a significant increase in E-cadherin mRNA and protein levels was observed. Moreover,overexpression of miR-148a,which had been verified to modulate DNMT1 expression, could reactivate the expression of E-cadherin. Knockdown of DNMT1 by DNMT1 siRNA could also increase the mRNA and protein levels of E-cadherin. Conclusion:The enforced expression of miR-148a may contribute to the reactivation of E-cadherin by suppression of DNMT1.