口腔癌前病变细胞凋亡状况及Bcl-2、Bax表达的研究

Study of Apoptosis and Bcl-2, Bax in Oral Precancerous Lesions.

目的 :通过对口腔白斑、扁平苔藓病变发展及癌变过程中细胞凋亡状况和凋亡相关蛋白表达水平的研究 ,探讨口腔白斑、扁平苔藓的癌变机理及病变机制。方法 :采用原位末端转移酶标记法及免疫组化法 ,观察分析 10例正常口腔黏膜上皮 ,18例扁平苔藓 ,2 3例白斑 ,2 2例口腔鳞癌上皮组织中细胞凋亡状况及凋亡相关蛋白Bcl- 2、Bax的表达水平。结果 :上皮 (轻 ,中 ,重 )不典型增生 ,鳞癌及糜烂型扁平苔藓的凋亡指数均高于正常 (P <0 .0 1)。Bcl- 2在白斑、扁平苔藓上皮细胞层无异常表达 ,但在扁平苔藓固有层淋巴细胞浸润处过度表达 ,在鳞癌组织中显高表达 (P <0 .0 1)。Bax在上皮单纯增生、轻、中度不典型增生和鳞癌及糜烂型扁平苔藓组织中显过度表达 (P <0 .0 5 )。结论 :白斑、扁平苔藓的病变发展及癌变过程中 ,上皮细胞凋亡状况发生了改变 ,Bax参与了白斑癌变的早期事件。扁平苔藓的发病机制与Bcl- 2。

Objective: To investigate the pathogenesis and carcinogenesis of oral leukoplakia (LK) and oral lichen planus (OLP). Methods: The apoptosis and the expression of Bcl-2 and Bax were obsevered in 10 cases of normal oral mucosa,18 cases of OLP, 23 cases of LK and 22 cases of oral squamous cell carcinoma (SCC) by TdT-mediated-dUTP nick end labeling (TUNEL) and immunohistochemical evaluation. Result: The number of epithelial apoptosis in (mild, moderate, severe) dysplasia, SCC, and erosive LP was significantly more than in normal oral mucosa(P<0.01). In the epithelial cell layer of normal mucosa, LK and OLP, the positive Bcl-2 expression was similar with normal oral mucosa. But, in the part of the lymphocytic infiltration of OLP, overexpression of Bcl-2 was observed. In the SCC, the expression of Bcl-2 was singnificantly higher than in normal oral mucosa(P<0.01). In the tissue of simple hyperplasia, mild dysplasia, moderate dysplasia, SCC and erosive OLP the expression of Bax were singnificantly higher than in normal oral mucosa(P< 0.05). Conclusions: Bax is realeated with early event of LK carcinogenesis and Bcl-2 and Bax play an important role in pathogenesis of OLP.