Figure 5

PI3K and ERK activation impairs caspase activation. A) HT29 cells were pre-treated for 30 minutes with DMSO (0.1%) or LY 249002 (20 μM) before being incubated with rhE-selectin/Fc (5 μg/ml for 24 hours). The proteins were extracted and were separated by SDS-PAGE and transferred onto a nitrocellulose membrane. Caspase-8 cleavage/activation was analysed by western blotting using specific anti-caspase-8 antibody. B) HT29 cells were pre-treated with MEK inhibitor PD059098 (50 μM for 60 min) with or without PI3K inhibitor LY294002 (20 μM for 30 min) or DMSO as vehicle (0.1% for 60 min) and treated or not with rhE-selectin/Fc (5 ng/ml for 24 hours). The proteins were extracted and were separated by SDS-PAGE and transferred onto a nitrocellulose membrane. Caspase-3 activation was analysed by western blotting using a specific anti-active-caspase-3 antibody and a specific antibody against vinculin as loading control.