Figure 5.

Suppression of CYLD expression by LEF1 is abolished upon selenite treatment. (a) A schematic representation of the LEF1-binding sites in the CYLD promoter. (b) Selenite treatment abolished LEF1 binding to the CYLD promoter. HCT116 and SW480 CRC cells were treated with selenite for 24 h and then subjected to ChIP analysis. (c and d) HCT116 and SW480 cells were transfected with siRNA-targeting LEF1 or scrambled control siRNA. At 48 h post-transfection, the cells were treated with 10 μM selenite for an additional 24 h and then subjected to FACS and western blot analysis. (e) Overall LEF1 protein levels and distribution remained constant after selenite treatment. Nuclear and cytoplasmic proteins were fractioned from selenite-treated HCT116 and SW480 cells and subjected to western blot analysis using antibodies against LEF1. B23 and β-actin were detected to demonstrate the purity of each fraction