Claudin 1 mediates tumor necrosis factor alpha-induced cell migration in human gastric cancer cells

Figure 5 Tumor necrosis factor α induces claudin 1 expression in gastric cancer cells. A: Western blotting revealed that the basal expression level of claudin 1 was increased in a time-dependent manner at 24 and 48 h, which was further increased by tumor necrosis factor α (TNF-α) (20 ng/mL) stimulation in MKN28 cells; B: Western blotting revealed that the expression level of claudin 1 was increased by TNF-α (20 ng/mL) stimulation in several gastric cancer cell lines, including NUGC4, MKN45 and Kato-III; C: At 24 h after treating the cells with TNF-α, expression of claudin 1 protein was increased mainly in cytoplasm. MKN28 cells were immunostained with an anti-claudin 1 antibody and counterstained F-actin and nuclei with rhodamine phalloidin and DAPI, respectively.