鼻咽刷洗物MSH2基因甲基化在鼻咽癌早期诊断及预后判断中的作用

摘要

Objective To assess the role of methylation of MSH2 gene in DNA prepared from nasopharyngeal brushing samples for early diagnosis and prognosis of nasopharyngeal carcinoma. Methods The methylation - specific PCR was used to detect methylation level of MSH2 gene in DNA prepared from carcinoma tissues and nasopharyngeal brushing samples from 54 cases of nasopharyngeal carcinoma patients and 18 cases of chronic nasopharyngitic patients and 20 cases of healthy volunteer. Results The methylation expression rates of MSH2 gene in DNA prepared from carcinoma tissues and nasopharyngeal brushing samples from 54 cases of nasopharyngeal carcinoma patients were 75. 9% (41/54) and 70. 4% (38/54) .while there were no methylation in 18 cases of chronic nasopharyngitic patients and 20 cases of healthy volunteer. Methylation of MSH2 gene in DNA prepared from Carcinoma tissues and nasopharyngeal brushing samples had close correlation. It had no close correlation between methylation of MSH2 gene and clinical data of nasopharyngeal carcinoma patients. Conclusion Methylation of MSH2 gene in DNA prepared from nasopharyngeal brushing samples has high specificity in distinguishing cancers from normal tissues and has important clinical significance for early diagnosis of nasopharyngeal carcinoma, but it may not be used as an parameter in evaluating the clinical prognosis of nasopharyngeal carcinoma.%目的 探讨鼻咽刷洗物检测MSH2基因甲基化在鼻咽癌早期诊断及预后判断中作用.方法 运用甲基化特异性PCR检测54例鼻咽癌患者、18例慢性鼻咽炎患者和20例健康志愿者配对鼻咽部组织及鼻咽刷洗物中MSH2基因启动子区甲基化情况.结果 鼻咽癌患者鼻咽部癌组织MSH2基因甲基化频率75.9％ (41/54),鼻咽刷洗物70.4％ (38/54);而在慢性鼻咽炎患者和健康志愿者鼻咽部组织及鼻咽刷洗物中均未检测到MSH2基因启动子甲基化.鼻咽癌组织与鼻咽刷洗物中MSH2基因甲基化密切相关(r=0.87),MSH2基因甲基化与患者临床病理特征无明显相关关系.结论 鼻咽刷洗物检测MSH2基因甲基化具有肿瘤特异性,对早期诊断鼻咽癌有一定的临床应用价值,但目前尚不能作为判断鼻咽癌临床预后预测指标.