Study On Expression Of TRAIL, DR4, DR5 And The Correlation With Apoptosis In Skin Hemangioma

Background and objectiveHemangioma is the most common benign tumor of infancy. This vascular lesion has a specific natural history and is characterized by an early and rapid proliferation, which is followed, in most cases, by a phase of slow involution which usually lasts for several years, during which the tumor stabilizes and then spontaneous regresses. The mechanism of pathologic evolution of hemangioma is largely unknown, and the treatment remains unsatisfactory. In recent years more attention has been paid to the mechanism of its spontaneous involution, and the elucidation for it might result in more effective future therapeutic strategies. More and more studies demonstrate that apoptosis is associated with the regression of hemangioma and a few relevant cytokines may play roles. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a novel member of the TNF superfamily, is a signal molecule capable of inducing apoptotic cell death in a variety of cell types. The receptor system for TRAIL is complex, and so far 5 receptors have been identified, including two death receptors (DR) DR4 and DR5, two decoy receptors (DcR) DcR1 and DcR2, and, a soluble receptor called osteoprotegerin (OPG). Its death receptors can mediate apoptosis with the membrane form of TRAIL or with soluble TRAIL (sTRAIL). TRAIL induces apoptotic cell death only in tumorigenic or transformed cells but not in normal cells. Given TRAIL'S potent antitumor activity and safety shown in vitro and in vivo experiments, interest has focused on this ligand as a potential cancer therapeutic.