Fig. 4.

FXR positively regulates SNAI2 transcription. (a) Top: FXR inhibition reverses DCA-induced upregulation of SNAI2 and CDX2 in GES-1 cells. Bottom: Quantification of Western blot results normalized to β-actin. (b) GES-1 cells were transfected with FXR expression vector and siSNAI2 simultaneously. Top: Downregulation of SNAI2 blocks CDX2 enhancement by FXR overexpression. Bottom: Quantification of Western blot results. (c) AGS cells were transfected with SNAI2 expression vector and siFXR. Top: Upregulation of SNAI2 reverses the inhibition of CDX2 by FXR-specific siRNA. Bottom: Quantification of Western blot analysis results. (d) Serially truncated SNAI2 promoter constructs were cloned into pGL3-luciferase reporter plasmids and transfected into GES-1 cells. Four hours after transfection, the cells were treated with DCA for 24 h after which relative luciferase activities were determined. (e) qRT-PCR analysis of ChIP products validating binding of FXR to the SNAI2 promoter. **p < 0.01. N.S., not significant