Effect of the inhibition of caspase-
-8 and -9 expression on the activation of caspase
-9 in (A) SK-BR-
3 and (B) MCF-7 cells after paclitaxel and SB
1216 application. Specific caspase-3 siRNA, caspase-7 siRNA, caspase-8 siRNA and caspase-9 siRNA were used. Control cells were incubated without taxane and siRNA. After 36 h of incubation with the tested taxane (100 nM for SK-BR-3 cells and 300 nM for MCF-7 cells) and relevant specific siRNA, levels of cleaved caspases were determined using western blot analysis and relevant antibodies (see “Materials and methods”). Actin levels were used to confirm equal protein loading. The data shown were obtained in one representative experiment of two independent experiments.