喉鳞癌p53基因第7外显子的测序分析  

Detection of mutations in exon 7 of p53 from fresh tumor samples by single-strand conformation polymorphism and direct DNA sequencing

作　　者：张晓晴[1] 傅艳军[2] 刘四喜[2] 梁传余[2] 

机构地区：[1]成都华西医科大学第四附属医院耳鼻咽喉科,610041 [2]华西医科大学第一附属医院耳鼻咽喉科

出　　处：《中华耳鼻咽喉科杂志》2001年第2期142-145,T010,共5页Chinese Journal of Otorhinolaryngology

基　　金：国家自然科学基金! ( 3 95 0 0 160 );美国中华医学基金!会 (CMB)专项基金共同资助项目

摘　　要：目的　探讨p5 3基因与喉鳞状细胞癌的关系。方法　应用聚合酶链反应 单链构像多态性分析 (polymerasechainreaction single strandconformationpolymorphism ,PCR SSCP)银染系统和PCR产物直接测序技术 ,检测喉鳞状细胞癌新鲜或冰冻组织中抑癌基因p5 3第 7外显子的突变情况。结果　 6 0例喉鳞状细胞癌组织中使用SSCP检测发现 2 5例显示电泳迁移率的改变。对 2 5例SSCP阳性样本随机抽出 8例进行PCR产物直接测序 ,8例第 7外显子均在 2 5 0密码子上第 1、3位碱基缺失一个C。同时 ,2例在 2 48密码子上第 1位碱基缺失一个C ,从而导致移码突变 ;3例在 2 6 1密码子上第 1、3位碱基发生A→G的转换和T→G的颠换 ,导致错义突变。 1例在 2 49密码子上缺失一个G ,1例存在2 5 4密码子上第 1位碱基A→T的颠换 ,1例 2 6 2密码子上GGT→TCA。结论　提示p5 3基因第 7外显子的 2 48、2 5 0和 2 6 1位密码子可能在中国人喉鳞状细胞癌中突变率较高。Objective To detect mutations of exon 7 of p53 gene in laryngeal squamous cell carcinoma (LSCC) and analyze the relationship between the mutation and LSCC. Methods Fresh tumor samples from 60 LSCC patients were examined using polymerase chain reaction single strand conformation polymorphism (PCR SSCP) and direct DNA sequencing. Results An extra band in SSCP was shown in 25 out of 60 samples. Exon 7 of p53 were detected by direct DNA sequencing in 8 samples taken at random from 25 cases. In 8 cases, 1 base pair deletion CCC→CC in 250 codon which may result in frame shift mutation was shown. Simultaneously, in 3 cases, transversion AGT→GGG in 261 codon which may bring out missense mutation was found. In 2 cases, 1 base pair deletion CGG→GG in 248 codon was detected. In another case, 1 base pair deletion AGG→AG in 249 codon was detected. Transversion ATC→TTC in 254 codon was found in one of the cases.Transversion GGT→TCA in 262 codon was found in another case. Conclusion The codon 248、 250、261 may be “hot spots” in LSCC. Mutations and deletions in exon 7 of p53 gene occurred frequently in LSCC.

关 键 词：鳞状细胞癌 P53基因 DNA突变分析 基因缺失 单链构象多态 聚合酶链反应 

分 类 号：R739.65[医药卫生—肿瘤]