鼻咽癌,宫颈癌和肺癌中p53基因突变和表达的对比研究

目的对比研究ｐ５３在鼻咽癌、宫颈癌、肺癌中的表达及其与ｐ５３基因突变的关系，为进一步研究ｐ５３在癌变过程中的作用奠定基础。方法应用免疫组化结合ＰＣＲ－ＳＳＣＰ银染技术检测２４例鼻咽癌、９例宫颈癌、１０例肺癌中ｐ５３基因的表达与突变。结果２３／２４例鼻咽癌、６／９例宫颈癌、９／１０例肺癌有ｐ５３的过表达，在两种发病与ＤＮＡ致瘤病毒有关的鼻咽癌、宫颈癌中未能检测到ｐ５３基因突变；而发病与化学致癌物有关的肺癌中有５／１０例检测到有ｐ５３基因突变，其中１例发生在外显子８，４例发生在外显子５。这５例均有ｐ５３的过表达。结论（１）鼻咽癌、宫颈癌、肺癌中存在着ｐ５３蛋白的过表达。（２）肺癌中ｐ５３的过表达大部分与ｐ５３基因突变有关，而鼻咽癌与宫颈癌中ｐ５３过表达与ｐ５３基因突变关系不大，其与致瘤性ＤＮＡ病毒的作用是否有关有待进一步研究。

Mutation and expression of p53 gene in nasopharyngeal carcinoma, cervical carcinoma and lung cancer

Objective To investigate the mutation and expression of p53 tumor suppressor gene in nasopharyngeal carcinoma (NPC), cervical carcinoma and lung cancer. Methods 24 NPCs, 9 cervical carcinomas and 10 lung cancers were examined by immunohistochemical and PCR SSCP techniques. Results 23/24 (90.1%) NPCs, 6/9 (66.7%) cervical carcinomas and 9/10 (90.0%) lung cancers showed p53 overexpression. No NPC or cervical carcinoma had p53 mutations in exons 5 8 of the gene, whereas mutations were found in 5 lung cancers, one in exon 8 and four in exon 5. All five cases showed p53 overexpression. Conclusions Overexpression of p53 exists in NPC, cervical carcinoma and lung cancer. It is related to gene mutation in lung cancer, but not in NPC or cervical carcinoma. The DNA tumor viruses may be involved in the overexpression of p53 in NPC and cervical carcinoma.