摘要
应用聚合酶链反应─—单链构象多态性（ＰＣＲ－ＳＳＣＰ）和免疫组化方法，研究了１８例大肠腺癌组织ｐ５３基因的突变和表达。另对７６例大肠腺癌及１１２例大肠息肉石蜡存档组织ｐ５３的表达进行了检测。大肠癌ｐ５３基因突变率为４４％（８／１８），突变发生在第５～６外显子中，８８％（７／８）的突变病例ｐ５３表达阳性。ｐ５３表达与大肠癌临床病理因素及预后无关，但在早期及高分化腺癌中表达较强。增生性息肉及轻度不典型增生腺瘤ｐ５３表达阴性，腺瘤癌变中表达最高（Ｐ＜０．００１）。绒毛状腺瘤ｐ５３表达高（Ｐ＜０．０５）。大肠腺瘤、腺瘤癌变和腺癌的ｐ５３表达率分别为４％（３／７１）、８８％（２３／２６）和５１％（３９／７６）。结果表明，ｐ５３基因突变的作用发生在良性腺瘤转变为癌的阶段。检测ｐ５３能预测腺瘤的癌变倾向，有助于早期发现大肠癌。
Abstract Using a polymerase chain
reaction-single strand conformation polymorphism(PCR-SSCP)approach we
analyzed 18 human colorectal adenocarcinomas for mutations in exons
5,6,7,8 ofp53 gene.At the same time,p53 gene product expression was
studied immunohistochemically inthese 18 cases in frozen sections.The
expression of p53 protein was also immunohistochemicallystudied in
formalin-fixed paraffin embedded specimens of 76 colorectal
adenocarcinomas and 112colorectal polyps.Eight out of 18
cases(44%)tested showed a variant band indicative of a muta-tion in
exons 5～6 of p53 gene.Seven out of 8 cases(88%)with p53 gene
mutations were posi-tively stained for p53.There was no significant
correlation between p53 expression and clinico-pathological
manifestations and prognosis.But the strongest staining was
encountered in thosecases with well differentiated and early stages
of adenocarcinomas,while weaker staining was en-countered in poorly
differentiated and mucoid adenocarcinomas.p53 expression was not
observedin proliferative polyps and adenomas with low grade
dysplasia.The frequency of p53 expressionreached 88%(P<0.001)when
adenoma showed malignant change.Among three types of adeno-mas,p53
expression was most frequent in villous type(P<0.05).The frequency of
p53 expres-sion in adenoma,adenoma with malignant change and
adenocarcinoma was 4%,88%and 51%respectively.These indicate that
genetic changes of p53 gene play an important role in the
trans-formation from benign adenoma to adenocarcinoma.p53
immnunohistochemistry can be used as asurrogate marker for p53 gene
mutation for early discovery of colorectal adenocarcinomas.
出处
《中华肿瘤杂志》
CAS
CSCD
北大核心
1995年第5期332-335,I007,T001,共6页
Chinese Journal of Oncology
基金
国家"八.五"攻关基金
