自噬基因Beclin1在口腔黏膜癌变过程中的表达及其意义

Expression and significance of autophagy-related genes Beclin1 in carcinogenesis of human oral mucosa

目的已有研究表明细胞自噬水平的变化与肿瘤的发生、发展有关。本研究探讨自噬相关蛋白Beclin1在口腔黏膜癌变过程中的表达情况,分析其与口腔鳞癌发生、发展的相关性及意义。方法采用免疫组化法检测38例人口腔鳞状细胞癌和38例癌前病变及19例正常口腔黏膜标本Beclin1的表达。结果口腔鳞癌组中有8例Beclin1表达阳性(21%),与正常黏膜组(84%)、上皮单纯增生组(78%)、上皮异常增生组(71%)及原位癌组(73%)差异有显著性(P<0.01);19例正常口腔黏膜表达有16例为阳性,与上皮单纯增生组、上皮异常增生组及原位癌组差异无显著性(P>0.05),原位癌组阳性率较上皮异常增生组虽有升高但差异亦无显著性。结论 Beclin1在口腔黏膜癌变的过程中表达下调,在原位癌阶段自噬能力有所增加,癌变完成后自噬能力显著降低;自噬活性的下调可能与口腔鳞癌的发生、发展相关。

Objective Many studies have indicated that the change of autophagy might be related with the growth and development of tumor. This study was to investigate the expression and significance of autophagy-related gene Beclinl in carcinogenesis of human oral mucosa tissues,and explore their correlations to the carcinogenesis and development of oral squamous cell carcinoma（OSCC）. Methods Immunohistochemistry was used to detect the expression of Beclin1 proteins in 38 OSCC tissues,38 premalignant lesions and 19 normal oral normal mucosa tissues.Results The positive rates of Beclin1 was significantly lower in oral squamous cell carcinoma（21%）than in oral normal mucosa（84%）,oral hyperplasia mucosa（78%）,oral dysplasia mucosa（71%）and carcinomas in situation（CIS）（73%）（P〈0.01）. There were16 cases of positive expression in oral normal mucosa（16/19）,it was no significant difference between the groups of the oral hyperplasia mucosa,the oral dysplasia mucosa and the carcinomas in situation（CIS）（P〉0.05）. The positive rate was slightly elevated in the group of the carcinomas in situation,but the difference between the positive rates of the oral dysplasia mucosa and CIS was not significant. Conclusion Expressions of Beclin1 are down-regulated in carcinogenesis of human oral mucosa,but the ability of autophagy increased in the stage of the carcinomas in situation（CIS）,and the ability was significantly decreased after the completion of the oral squamous cell carcinoma. The results indicated that the decrease of autophagic capacity may relate to tumorigenesis and the development of OSCC.