颌骨成釉细胞瘤中细胞凋亡相关蛋白的表达

目的研究颌骨成釉细胞瘤中细胞凋亡相关蛋白的表达。方法采用免疫组化方法观察39例经典型成釉细胞瘤中凋亡相关蛋白Fas、Fas配体（Fas Ligand，FasL）、caspase-3和bcl-2及增殖细胞标记Ki67的表达，采用TUNEL法检测11例成釉细胞瘤中的凋亡细胞。结果39例成釉细胞瘤中分别有35（89．7％）、34（87．2％）及21（61．5％）例表达Fas、FasL和caspase-3，阳性染色主要分布于上皮岛中心呈鳞状化生和颗粒变性的细胞，TUNEL法标记的凋亡细胞也集中于这些区域。bcl-2和Ki67阳性染色则主要位于上皮岛周边的基底细胞。结论Fas／FasL介导的细胞凋亡机制可能在成釉细胞瘤中肿瘤细胞的分化、变性及被清除过程中发挥作用。

Expression of apoptosis - related proteins in ameloblastomas of the jaws

Objective To investigate the expression of some apoptosis-related proteins in human ameloblastomas of the jaws,in an effort to clarify the possible roles of apoptotic cell death in the oncogenesis and cytodifferentiation of ameloblastomas. Methods The expression of Fas,Fas Ligand(FasL),caspase-3 and bcl-2 proteins,as well as cell proliferation marker Ki67,were examined immunohistochemically in 39 ameloblastomas.TUNEL method was used to detect the apoptotic cells in 11 cases. Results Fas,FasL,and caspase-3 were expressed in 35((89.7%)),34((87.2%)),and 24((61.5%)) cases of ameloblastomas,respectively.More intensive reactivity were observed in the central cells of tumor nests,especially those exhibiting squamous metaplasia or granular transformation.Apoptotic cells detected by TUNEL method also tended to situate in such areas.By contrast,bcl-2 and Ki67 were expressed mainly in the peripheral basal cells of the tumor nests. Conclusion Fas/FasL-induced cell death pathway may play a role in the cytodifferentiation and clearance of the central tumor cells in the odontogenic epithelial islands of ameloblastoma.