Abstract：Objective To study the 5-azacytidine’s demethylation for dickkopf-related protein 3 (DKK3) gene and its effects on SGC7901 gastric cancer cells’ proliferation and apoptosis. Methods SGC7901 gastric cancer cells were treated with 5-azacytidine, and other SGC7901 gastric cancer cells without 5-azacytidine treatment served as the controls. The changes of DKK3 gene promoter’s methylation and the differences in cell proliferation curve, cell proliferation and apoptosis were compared. Results DKK3 gene in SGC7901 gastric cancer cells showed methylation before 5-azacytidine treatment, but showed unmethylation after 5-azacytidine treatment, indicating that 5-azacytidine induced DKK3 gene promoter’s demethylation. The proportion of G0/G1 phase, proliferation index (PI) and apoptosis rate in SGC7901 gastric cancer cells after 5-azacytidine treatment were all significantly higher than those in SGC7901 gastric cancer cells before 5-azacytidine treatment (all P<0.05), whereas the S-phase and G2/M phase in SGC7901 gastric cancer cells after 5-azacytidine treatment were both significantly lower than those in SGC7901 gastric cancer cells before 5-azacytidine treatment (both P<0.05). Conclusions DKK3 may be an anti-oncogene. 5-azacytidine can demethylate DKK3 gene promoter’s methylation, which can promote SGC7901 gastric cancer cells’ apoptosis and inhibit their proliferation.
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2018, Vol. 25 
