婴幼儿血管瘤组织中bcl-2和bax与细胞凋亡的研究

Apoptosis and expression of bcl-2 and bax in infantile hemangioma

目的 研究凋亡调控基因bcl- 2和bax与婴幼儿血管瘤细胞增生、凋亡的关系,探讨其在血管瘤增生、消退中的作用机制。方法 采用免疫组化SP法检测血管瘤及血管畸形组织中增殖细胞核抗原(PCNA)及凋亡调控基因bcl -2和bax的表达;用末端脱氧核苷酸转移酶(TdT)介导的d UTP生物素缺口末端标记技术 (TUNEL)检测凋亡细胞。结果 bcl 2阳性表达率在增生期和消退期分别是82.14%和46.67%,两者之间差异存在显著性意义(P<0.01),消退期与血管畸形表达差异无显著性意义(P>0.05)。Bax在血管瘤增生期和消退期均为 100%表达,与血管畸形中的表达差异有显著性意义(P<0.01)。bcl 2和bax在血管畸形组织中均不表达。婴幼儿血管瘤增生期和消退期凋亡指数(apop tosisindex,AI)为30.52±10.25和80.22±6.82;增殖指数 (proliferativeindex,PI)分别为11.40±8.90和4.79±3.63,两者之间差异均存在显著性意义(P<0.01)。AI与bcl 2的表达呈负相关 (r=-0.318,P<0.05),AI与bax的表达无明显相关性 (r=-0.077,P>0.05),AI与bcl 2/bax比值呈负相关 (r=-0.307,P<0.05)。结论 在血管瘤增生消退中存在着逐渐活跃的凋亡现象,细胞凋亡是血管瘤的典型生物学特征,是血管瘤的自然消退的关键因素。bcl -2和bax参与了血管瘤中细胞凋亡的调节。

Objective To investigate the roles of proliferation and apoptosis in the regression of infantile hemangioma.Methods Immunohistochemical stainings for PCNA, bcl-2 and bax were conducted on formalin-fixed, paraffin-embedded tissues of hemangiomas and vascular malformations. The apoptotic cells in tissues of hemangioma and vascular malformation were detected by terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL).Results There was a significant difference of bcl-2 expression between proliferative and involuting phase of hemangioma ( 82.14% vs 46.67%). However, there was no significant difference of bcl-2 expression between involuting hemangioma and vascular malformation. The positive rate of bax was 100% in hemangioma. The ratio of Bcl-2/bax is higher in proliferative phase of hemangioma than that in involuting hemangiomas. No expression of bcl-2 and bax in vascular malformations could be noted. Apoptotic index (AI) in proliferative hemangiomas was lower than that in involuting phase hemangiomas (P< 0.01). The proliferative index (PI) in proliferative hemangiomas, on the other hand, was higher than that in involuting phase hemangioma (P< 0.01). There was a significant negative correlation between AI and the expression of bcl-2.Conclusions Increased apoptosis during pathologic process of hemangioma plays an important role in regression of the hemangioma.