Kaurene diterpene induces apoptosis in human leukemia cells partly through a caspase-8-dependent pathway - Kondoh,M.; Suzuki,I.; Sato,M.; Nagashima,F.; Simizu,S.; Harada,M.; Fujii,M.; Osada,H.; Asakawa,Y.; Watanabe,Y. (J Pharmacol Exp Ther, 2004)