Thaspine acetate, an alkaloid, is a topoisomerase I and II inhibitor. Thaspine acetate induces cancer cell apoptosis. Thaspine acetate induces Bak and Bax activation, mitochondrial cytochrome c release and mitochondrial membrane permeabilization. Thaspine acetate can be isoalted from the cortex of the South American tree Croton lechleri.