Snail is crucial for TNFα-induced EMT.

<p>(A) pcDNA-Snail (Snail) or control vector pcDNA-3.1 (Vector) were expressed in HCT116 cells for 48 h. Cell morphological changes associated with EMT are shown in the phase contrast image. Expression of E-cadherin and N-cadherin were analyzed by immunofluorescence staining. Nuclei were visualized with DAPI staining. Scale bars: 20 µm. (B) The expression of E-cadherin, N-cadherin and Snail from HCT116 cells transfected with pcDNA-Snail or control vector were examined by western blotting. β-actin servers as the loading control. (C) HCT116 cells transfected with Snail specific si-RNA (si-Snail) or negative control si-RNA (si-NC) were stimulated with or without TNFα (20 ng/ml) for 48 h, and the morphologic changes were observed with a phase-contrast microscopy. (D) HCT116 cells transfected with si-Snail or si-NC were stimulated with or without TNFα (20 ng/ml) for 4 days, and the expression of E-cadherin and Snail were detected by western blotting. β-actin servers as the loading control.