The role of XIAP and Smac in the development of pediatric hemangioma

Abstract

Objective To investigate the role of X-linked inhibitor of apoptosis protein (XIAP)and second mitochondria- derived activator of caspase (Smac) in hemagioma regression. Methods Thirty-one hemangioma specimens were categorized according to Mulliken's classification and the expression of proliferating cell nuclear antigen (PCNA). The expression of XIAP and Smac were assayed with immunohistochemistry method. Results There were 18 proliferating phase specimens and 13 involuting phase specimens. In the proliferating phase specimens, the IOD(integral optical density) of XIAP and Smac expressions were 2421.03 ± 792.91 and 472.05 ± 182.16 respectively. In the involuting phase specimens,the IOD of XIAP and Smac expressed were 443.24 ± 105.15 and 2074.10 ± 320.41 respectively. In the proliferating phase specimens, the IOD of Smac expression was significantly lower than the IOD in the proliferating phase specimens (P＜0.01 ). In the proliferating phase specimens, the IOD of XIAP expression was significantly higher than the IOD in the involuting phase specimens (P＜0.01). XIAP negatively correlates with Smac (r= -0.753,P＜0.01 ). Conclusions The interaction of XIAP and Smac may resulted in hemangioma regression. Key words: Hemangioma; X-linked inhibitor of apoptosis protein; Second mitochondria- derived activator of caspase