中文摘要：

目的 探讨血清游离DNA甲基化水平检测对胶质瘤的意义.方法 采用亚硫酸氢盐测序（BSP）法检测65例胶质瘤患者血清、组织和30例正常血清Alu甲基化水平并进行分析.结果 患者血清中Alu平均甲基化水平为47.30％[（35.40±54.25）％],正常血清是57.90％[（55.25±61.45）％,P＜0.01]；肿瘤组织Alu平均甲基化水平为40.30％[（36.80±54.20）％],与血清中一致（r=0.882）；另外,高级别组的甲基化水平都低于低级别组（P＜0.01）；Alu甲基化水平越高预示更高的生存率（P＜0.01）；受试者工作特征（ROC）曲线下面积（AUC）为0.861（0.789 ～ 0.933,P＜0.01）.结论 血清游离DNA中Alu低甲基化的检测有助于胶质瘤的诊断及预后判断.

英文摘要：

Objective To investige the roles of measuring hypomethylation of serum Alu elements （Alu） in glima.Methods Tumor tissues and matched serum specimens from 65 glioma patients and serum samples from 30 healthy controls were examined for Alu hypomethylation by bisulfite sequencing.Results The median serum Alu methylation level was 47.30％ in patients [interquartile range （IQR）,（35.40 ± 54.25） ％] and 57.90％ in the controls [IQR,（55.25 ± 61.45） ％].The median Alu methylation level in tumor samples was 40.30％ [IQR,（36.80 ± 54.20） ％],which showed the correlation of Alu hypomethylation between tumor and serum samples （r =0.882） in the study group.The methylation level was higher in the low-grade glioma group than in the high-grade group in tumor and serum samples.A correlation between high methylation level and longer survival time was detected in tumor and serum samples.Receiver operating characteristic （ROC） curve analysis revealed that the area-under-the-curve （AUC） for diagnosis was 0.861 （95％ confidence interval：0.789 ± 0.933）,suggesting that Alu hypomethylation in serum may be of diagnostic value.Conclusion Our results indicate that the detection of Alu hypomethylation in serum may be clinically useful for the diagnosis and prognosis of glioma.