Although the best characterized biological activity of TRAIL, also known as Apo2 ligand, is represented by a potent induction of apoptosis in a variety of cancer cell types [2], the wide expression of TRAIL and TRAIL receptors in many normal tissues suggests that the physiological role of TRAIL is more complex than merely activating the apoptotic pathway in cancer cells. The gene discussed is TNFSF10; the disease is cancer.