CASP9 and cancer: Both in vitro and in vivo studies have demonstrated that eugenol-treated cancer cells have variations in their mitochondrial membranes demonstrated by a decrease in anti-apoptotic Bcl-2 expression and translocation of pro-apoptotic Bax that led to cyt-c release into the cytosol and subsequent activation of caspases-9 and -319, 21, 24.