Fig. 5

TFF1 enhances the function of GKN2. a-b Analyses of apoptosis with or without TFF1 after H₂O₂ (300 uM, 6 h) treatment. c Detection of TFF1 expression after TFF1 was knockdown in GC cell lines. GC cells were transfected with siRNA (100 nM) and 24 h after transfection TFF1 expression was evaluated. d Comparison of the proliferation of GC cell lines with or without TFF1 knockdown. Cells were pre-treated with H₂O₂ (300 uM) for 6 h. GKN2 overexpressing MGC cells (IC50 528.4 ± 29.5 μM) were significantly more sensitive to H₂O₂ compared to GKN2 overexpressing MGC cells with silence of TFF1 (IC50: si1 620.9 ± 33.6, P < 0.05; si2 618.4 ± 30.2, P < 0.05). In SGC cells, GKN2 overexpressing cells (IC50 539.2 ± 31.6 μM) were significantly more sensitive to H₂O₂ compared to GKN2 overexpressing cells with silence of TFF1 (IC50: si1 609.2 ± 23.3, P < 0.05; si2 614.1 ± 27.3, P < 0.05). e The stability assays of Hsc70 after overexpression of TFF1 in control and GKN2-overexpressing GC cell lines. The cells were treated with 10 μM cycloheximide for 12 h then treated with H₂O₂ (300uM, 6 h). f The expression and ubiquitination of Hsc70 after overexpression of TFF1 in control and GKN2-overexpressing GC cell lines. Cells were treated with H₂O₂ (300 uM) for 6 h. Data represent similar results from three independent experiments. (**p < 0.01, ***p < 0.001)