乳腺增生病p53基因第5外显子突变及其蛋白表达

目的：探讨p53基因在乳腺癌发生早期的作用。方法：用免疫组化方法检测36例乳腺单纯性增生、31例不典型增生、14例原位癌和16例浸润癌中p53蛋白的表达，用PCR－SSCP检测了上述组织中p53基因第5外显子突变。结果：p53蛋白在单纯性增生、不典型增生、导管内癌、浸润癌中的表达率分别为0、22.6%(7/31)、42.8%(6/14)、50％（8／16），PCR－SSCP在各组中均未检测到该基因第5外显子突变。结论：乳腺癌发生早期阶段有p53基因的参与，但与第5外显子突变无明显关系。

Mutations of exon 5 of p53 gene and expression of p53 protein in human breast hyperplasia

Purpose To investigate the role of p53 gene in carcinogenesis of the early stages of human breast lesions. Methods 36 cases of epithelial hyperplasia of usual type, 31 cases of atypical hyperplasia, 14 cases of breast intraductal carcinoma and 16 cases of breast invasive carcinoma were employed to detect expression of p53 protein immunohistochemically, and to detect mutations of exon 5 of p53 gene by PCR-SSCP assay. Result Expression of p53 protein were found in 22.6%(7/31) of breast atypical hyperplasia, 42.8%(6/14) of intraductal carcinoma and 50%(8/16) of invasive carcinoma. p53 protein expression was not observed in hyperplasia of usual type. All tested samples of breast cancer and hyperplsia showed no mutations of p53 gene at exon 5. Conclusion Overexpression of p53 protein is involved in early stages of breast carcinogenesis, which is not associated with mutations of exon 5 of p53 gene.