吸入性烟尘与大鼠肺组织p53蛋白表达和基因突变的关系

The Relation between Smoking and Gene Mutation and Protein Expression of p53 in Rat Lung Tissue

目的分析吸烟对p53在肺组织中表达的影响,研究吸烟与p53基因突变的关系,探讨吸烟导致肺癌的发生发展,为临床上吸烟对肺造成损伤的判定及吸烟者肺癌的早期诊断提供理论依据。方法建立大鼠烟雾吸入模型,常规石蜡切片HE染色,光镜观察肺泡结构等变化情况;免疫组织化学SP法检测吸烟各个设定时期p53蛋白的表达情况;从超低温冷冻肺组织标本中抽提DNA,以PCR-SSCP法检测p53第5～8外显子在吸烟各阶段的突变情况。所得数据采用SAS软件作统计学处理分析,比较各组间差异程度。结果吸烟可以导致大鼠肺泡腔不规则扩大,肺泡壁变薄或断裂,呼吸性细支气管呈囊状扩张,肺泡相互融合成肺大泡,伴有中性粒细胞、淋巴细胞及巨噬细胞等炎性细胞浸润。p53蛋白表达阳性率随吸烟时间的延长而升高（P〈0.05）,p53基因突变率也随吸烟时间的延长而增加（P〈0.05）,并呈逐渐上升趋势。结论在吸烟所致肺癌的发生发展中p53基因的突变是早期事件,为通过筛选吸烟者痰液中脱落细胞中的p53基因突变进行肺癌的早期诊断提供了理论依据。

Objective To analyze the influence that p53 expressed in lung tissue, to research the relation between smoking and p53 gene mutation ,and to investigate the development of smoking-related lung cancer, These can provide us with theorial evidence judging lung lesion and early diagnosis smoking-related lung carcinomas clinically. Methods The model of rat smoking was build up. HE dyeing was used to observe the transform of alveoli ＇s＇ structure, lmmunohistochemistry was used to detect the expression of p53 in every cigarette-used setting period. DNA of refrigerant lung tissue was extracted and used to analyze the gene mutation of p53 exons 5 - 8 by PCR-SSCP. SAS was used to deal with the data that we got. Results The smoking groups＇ alveolar spac, e had different degree dilation, and alveolar wall became capsular to expand, and alveolar were mixed together to form pneumatoeele.There were inflammatory cells infiltrate, such as neutrophil, lymphocyte and maerophage in alveolar septum. The positive ratio of p53 protein expression was inereased with prolonging smoking time （ P 〈 0.05 ） , The mutation of p53 was increased with smoking time（ P 〈 0.05 ） . Conclusion p53 gene mutation was early event in the carcinogenesis and development of rat lung eareinoma induced by smoking. These provided us with theorial evidence early diagnosising smoking-related lung carcinomas through screening p53 gene mutation of east-off in smoker＇s sputamentum.