AAV3-mediated expression of the pyruvate dehydrogenase E1 alpha subunit gene can also result in the apoptosis of liver cancer cells [15]. Tumor necrosis factor (TNF) related apoptosis-inducing ligand (TRAIL) receptor 2 (also called death receptor 5, DR5) is usually expressed in tumor cell lines but not in normal cells. Investigators have demonstrated that an AAV-based anti-DR5 mouse-human chimeric antibody can markedly inhibit tumor growth in vitro and in vivo [88].