Role of NF-κB in acid-induced DNMT1 expression. A: SN50, a cell permeable inhibitor of NF-κB significantly decreased acid-induced DNMT1 mRNA expression. B: in BAR-T cells, knockdown of NF-κB1 p50 with p50 siRNA significantly decreased acid-induced DNMT1 mRNA expression. C: in CP-A cells, knockdown of NF-κB1 p50 with p50 siRNA significantly decreased acid-induced DNMT1 mRNA expression. D: in FLO EA cells, knockdown of NF-κB1 p50 with p50 siRNA significantly decreased acid-induced DNMT1 mRNA expression. E: acid-induced increase in DNMT1 promoter activity was significantly decreased by knockdown of NF-κB1 p50 with p50 siRNA in BAR-T cells. F: in BAR-T cells, overexpression of NF-κB p50 significantly increased DNMT1 promoter activity (n = 3). ANOVA: *P < 0.001, compared with control or control siRNA group; **P < 0.05, ***P < 0.001, compared with control + acid group or control siRNA + acid group. ▲P < 0.05 by t-test.