The Antioxidant Alpha-Lipoic Acid Inhibits Proliferation and Invasion of Human Gastric Cancer Cells via Suppression of STAT3-Mediated MUC4 Gene Expression

Figure 3

Alpha-lipoic acid inhibits TNF-α-induced MUC4 in gastric cancer cell lines. (a) AGS, BGC-823, and MKN-28 cells pretreated with the indicated concentrations of ALA for 24 h were treated with 20 ng/mL TNF-α for 4 h. After TNF-α treatment, RT-PCR was performed to analyze the MUC4 mRNA. (b) AGS, BGC-823, and MKN-28 cells pretreated with 0, 0.5, 1, or 2 mM ALA for 24 h in RPMI with 10% FBS were treated with or without 20 ng/mL TNF-α. And then, western blotting was performed to analyze the expression of MUC4 at protein levels. (c) The pGL3-MUC4 promoter construct-transfected AGS cells were pretreated with the indicated concentrations of ALA for 24 h, then incubated with 20 ng/mL TNF-α for 4 h and luciferase activity was determined using a luminometer. Data represent from 3 independent experiments. compared to only TNF-α treatment group.

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