应用非同位素PCR-SSCP方法检测乳腺癌p53基因点突变

目的　探讨乳腺癌组织中p53基因点突变。方法应用非同位素PCR -SSCP技术检测 4 8例石蜡包埋乳癌组织中p53基因点突变。结果　 4 8例乳腺癌中 2 0例出现异常电泳 ,表明这些病例相应DNA片段中发生了点突变 ,其中 8例位于第 5- 6外显子 ,9例位于第 7外显子 ,3例位于第 8外显子。免疫组化检测突变p53蛋白的表达 2 5例为阳性 ( 52 % ) ,其中 5例SSCP未发现基因突变 ,突变可能发生在所检测的基因片点以外。结论　非同位素PCR -SSCP是一简便、快速、有效的检测基因点突变的方法 ,特别适用于大量标本基因点突变的筛选 ;p53基因点突变与突变型蛋白表达呈相关关系

DETECTION OF POINT MUTATION OF p53 GENE BY NON-ISOTOPIC PCR-SSCP IN BREAST CANCER TISSUE

Objective To investigate the point mutation of p53 gene in breast cancer tissues. Methods Non-isotopic PCR-SSCP method was used to detect point mutation of p53 gene in 48 of breast cancers. Results The abnormal shifting of the single-strand DNA (ssDNA) was identified in 20 out of 48 cases. The point mutation of 8 cases were found in exons 5-6, 7 in exon 7, 3 in exon 8. The positive nuclear staining was observed in 25 cases(52%)By immunohistochemistry, among which 5 cases didnt show point mutation in SSCP analysis. The mutations might occur in the regions which were not examined in this study. Conclusion Our results indicate that detection of point mutations of p53 gene bu PCR-SSCP method is more accurate and reliable than that by immunohistochemistry and non-isotopic PCR-SSCP is especially useful in the screening of point mtations during handling a large number of samples.