【摘要】 目的：探讨胸腺癌中p53蛋白过表达对癌细胞增殖和凋亡的影响。方法：收集手术切除的胸腺标本20例。用抗p53蛋白(DAKODO7)和抗增殖细胞核抗原(PCNA,DAKOclonePC10)的单抗,采用LsAB免疫组化法染色。以平均每100个癌细胞中p53阳性细胞数为p53表达率，阳性p53蛋白细胞数超过20％者称为p53蛋白过表达，以平均每100个癌细胞中PCNA阳性细胞数为增殖指数(proliferationindex,PI)。采用BoehringerMannheim公司的原位细胞死亡试剂盒检测凋亡细胞，癌细胞的凋亡指数(apoptosisindex，AI)定为平均每个高倍视野中的凋亡细胞数。结果：20例胸腺癌中的19例可见p53阳性癌细胞，p53蛋白表达率为95％(19/20),过表达率达35％(7/20)。p53蛋白表达率与AI之间有负相关性(P<0.05)。7例有p53蛋白过表达的平均AI为0.5/HPF，明显低于13例无p53蛋白过表达的平均AI(4.5/HPF),P<0.05。结论：95％的胸腺癌中有p53蛋白表达，35％有p53蛋白过表达，说明p53的基因变异可能参与了某些胸腺癌的癌变过程。过表达的p53蛋白在胸腺癌中已丧失了野生型p53蛋白抑制细胞增殖和诱导受损细胞凋亡的作用，从而促进了胸腺癌的生长进展。更多还原

【Abstract】 Objective： To investigate the effects of p53 overexpression on neoplastic cell proliferation and apoptosis in 20 cases thymic carcinomas. Methods： Twenty surgical samples of thymic carcinoma were collected for this study. Immunohistochemical staining was performed by using LsAB method with anti p53 monoclonal antibody (DAKO DO 7) and prolife rating cell nuclear antigen (PCNA, DAKO clone PC10) antibody as primary antibodies. The p53 expression rate was indicated by number of p53 positive cells per 100 carcinoma cells. More than 20％ of p53 positive cells found in tissue section was considered as p53 overexpression. Proliferation index (PI) was indicated as average number of PCNA positive cells in 100 carcinoma cells. Boehringer mannheim in situ cell death detection kit was used for observation of apoptotic neoplastic cells,and apoptotic index(AI) was defined as apoptotic cells averagely found in a high power view microscopically. Results： p53 positive cells were found in 19 out of 20 cases thymic carcinomas, the expression rate reached 95％ and the overexpression rate was 35％ (7/20) . There was a negative correlation between p53 expression rate and AI. The mean AI (0.5/HPF) of 7 cases thymic carcinomas with p53 overexpression was lower than that (4.5/HPF) of 13 cases thymic carcinomas without p53 overexpression, P< 0.05. Conclusion： The p53 alteration might involve in carcinogenesis of some thymic carcinoma. The overexpressed p53 protein had lost its wild type functions as proliferation inhibitor and apoptosis inducer, and hence could promote the growth of thymic carcinomas.更多还原