Earlier and recent studies have showed that a high ratio of Bax to Bcl-2, activation of caspase family, including caspase-3, caspase-8 and caspase-9, as well as the loss of mitochondrial transmenbrane potiential are observed in monensin-induced apoptosis of several human cancer cell lines [10,13–18]. The gene discussed is CASP9; the disease is cancer.