CASP9 and neoplasm: To further analyze whether the intrinsic pathway (i.e., caspase-9) was involved in the proapoptotic action of BGT226 in HCC cells, we examined the effect of the pan-caspase inhibitor Z-VAD-fmk, whose activity has already been analyzed in different tumor cell lines [31, 32], administered alone and in combination with BGT226 for 24 h in Mahlavu and SNU449 cells.