Recent studies have found that JNK activity is involved in the regulation of cell proliferation and apoptosis (Davis, 2000; Lin, 2003), and the inhibition of the JNK pathway with SP600125 is well known to result in cell cycle arrest, endoreduplication, and apoptosis in various cancer cells (Hideshima et al., 2003; Du et al., 2004; Mingo-Sion et al., 2004). The gene discussed is MAPK8; the disease is cancer.