The increasing Bax/Bcl-2 ratio also enhances the expression of cytochrome C. Cytochrome C can not only directly disrupt the mitochondrial membrane, inducing cancer cell apoptosis, but also can form apoptosomes with Caspase9 and Apaf-1, activating the expression of Caspase3 and inducing cancer cell apoptosis. This evidence concerns the gene APAF1 and cancer.