CASP9 and central nervous system cancer: To evaluate the mechanism of apoptosis induced by co-infection with Adv-p53, Adv-APAF1 and Adv-Casp9 in glioma cells, we examined the expression of apoptosis-related genes including Bax, p21/WAF1, Bcl-XL, caspase-3, PARP and Fas.