Fig. 4: HNSCC-associated caspase-8 mutants display differential capacities to mediate TRAIL-induced cell death.

HeLa-CASP8 KO cells engineered for DOX-inducible expression of WT caspase-8, MT caspase-8 proteins, or LacZ were pre-treated in quadruplicate with DOX (1 μg/mL), followed by treatment with DOX plus varying concentrations of TRAIL for an additional 48 h before the performance of crystal violet (upper panel) or MTT (lower panel) assays. Columns represent the means from quadruplicate wells; error bars represent the SEM. One-way ANOVA was used to compare multiple groups. Experiments were performed three times with similar results.