食管癌变过程中p53表达及其与细胞凋亡水平的关系

Expression of p53 and Cell Apoptosis during Carcinogenesis in Esophageal Carcinoma

[目的]探讨食管癌变过程中食管鳞状上皮p53表达情况及其与凋亡水平的关系。[方法]824例食管黏膜活检组织(包括正常黏膜、异型增生和鳞癌),行DNA末端标记(TUNEL法)检测及p53免疫组化检查。[结果]①轻—中度不典型增生组p53表达阳性率高于正常及炎症组和良性增生组(P=0.003),低于重度不典型增生/鳞癌组(P=0.036);良性增生组与轻—中度不典型增生组间无明显差异(P=0.192);②正常及炎症组和良性增生组随年龄增长p53表达呈上升趋势(P<0.01);轻中—度不典型增生组及重度不典型增生组各年龄组间差异不明显;③随着p53表达的增加,上皮颗粒层细胞凋亡指数(AI)逐步下降(χ2=87.266,P=0.000),基底层AI呈轻度增加趋势(χ2=34.253,P=0.000)。[结论]食管癌变过程中伴有p53基因的突变和颗粒层细胞凋亡水平的下降,且两者关系密切。

[Purpose] To investigate expression of p53 and cell apoptosis during carcinogenesis in esophageal carcinoma. [Method] The expression of p53 and the changes of apoptosis in tissue samples from 824 cases of esophageal mucosal biopsy （including normal mucosal epithelium, dysplasia and squamous cell carcinoma） were detected by immunohistochemistry and TUNEL method. [Results] ①The positive rate of p53 in mild-moderate dysplasia group was higher than that in normal and benign hyperplasia group（P=0.003）, and lower than that in severe dysplasia/carcinoma group（P=0.036）. There was no significant difference between normal group and benign hyperplasia group （P=0.192）. ②In normal and benign hyperplasia group, the positive rate of p53 tended to increase with the age growth（P0.01）. In mild-moderate dysplasia group and severe dysplasia/carcinoma group no significant difference was found between different age groups. ③As the expression of p53 increasing, the apoptosis index （AI） decreased significanty in esophageal epithelial granular cells（χ2=87.266,P=0.000）, and showed a slight increasing trend in the basal layer（χ2=34.253,P=0.000）. [Conclusion] The process of esophageal carcinogenesis associates with p53 gene mutation and apoptosis levels decreases in the granular layer.