Figure 5.

Slug/SNAI2 binds directly to the OPN promoter and enhances its transcriptional activity. (A) Luciferase activity in HT-29 control cells (black) and in Slug-transfected HT-29 cells (gray) of the proximal (−213/+87) and the distal (−1206/+87) OPN promoter. The fold induction was calculated after normalization with empty vector. Cells were co-transfected with RSV-β-galactosidase to normalize the luciferase activity. The graphs represent the mean of 3 independent experiments. Bars, SEM. Data were considered significant if p was less than 0.05 as determined by the two-tailed Student’s t-test. Symbols: ** p < 0.01, NS, not significant. (B) The proximal promoter region of OPN by BLAST, indicating the putative Slug binding sites (e-box) and the primers (red arrows) that were used. (C) Chromatin immunoprecipitation (ChIP) analysis with a Slug-directed antibody in parental, control, and Slug-transfected cells.