中国人食管癌 p16 基因突变分析

为了解ｐ１６基因与中国人食管癌遗传易感性的关系，应用ＰＣＲ－ＳＳＣＰ银染法和ＤＮＡ序列测定法对４０例食管癌及相应手术切端正常组织ＤＮＡ标本ｐ１６基因进行研究，结果在４０例食管癌标本ＤＮＡ中共发现ＤＮＡ变异１４例，其中９例存在有ｐ１６基因的错义突变和剪接位点突变，５例分别在密码子４１和１４０存在与白种人已发现的相同的正常多态现象，而相应的正常手术切端组织标本中未发现有错义突变和剪接位点突变。提示：（１）中国人食管癌中存在较高频率的ｐ１６基因突变，并以错义突变为主；（２）高发区和普通人群食管癌标本中ｐ１６基因突变频率未见差异；（３）正常对照手术切端组织未发现相应体细胞突变。表明ｐ１６基因突变在中国人食管癌发展过程中属较晚期的改变。

MUTATION ANALYSIS OF p16 GENE IN ESOPHAGEAL CARCINOMAL IN CHINA

To understand the relationship between p16(MTS1) gene and the susceptibility of esophageal cancer, 40 primary squamous cell carcinomas of esophagous and their paired normal esophageal tissues at the resection ends were detected using PCR SSCP silver stain method and DNA sequencing. 14 mutations were found altogether in these 40 samples. 9 of 40 tumors had missense or splicing site mutations. 5 tumors had polymorphisms at condon 140 and condon 41 respectively. In the matched normal esophageal tissues, no mutation was found. These indicated:(1) high frequency mutations of p16 gene, especially missense mutations, exist in esophageal cancer tissues in Chinese; (2) no difference has been found in the mutation frequencies between high incidence area and normal populations; (3) no somatic mutations have been found in the resection end tissues. The results suggest that p16 gene mutations may play a role at the later stage of tumorigenesis in esophageal cancer in China.