甲基化敏感性高分辨率熔解曲线分析筛查大肠癌的性能评价

目的：评价通过甲基化敏感性高分辨率熔解曲线分析（MS‐HRM）检测粪便中人DNA甲基化筛查大肠癌（CRC）的性能。方法收集合格的新鲜粪便标本82例，其中CRC患者27例（CRC组）、进展期腺瘤（AA）患者25例（AA组）和结肠镜阴性的正常人30例（对照组），在LightCycler480设备上应用MS‐HRM技术检测上述粪便中vimentin基因的甲基化状态，并与粪便潜血试验（FOBT）的诊断性能相比较。结果MS‐HRM在CRC组、AA组和对照组中检测vimentin基因甲基化的阳性率分别为81．5％（22／27），80．0％（20／25）和6．7％（2／30）。FOBT在CRC组、AA组和对照组中的阳性率分别为37．0％（10／27），12．0％（3／25）和3．3％（1／30）。在病例组中，MS‐HRM和FOBT的诊断敏感性分别为80．8％（42／52）和25．0％（13／52），前者显著高于后者（P＜0．05）；在对照组中两者的诊断特异性分别为93．3％（28／30）和96．7％（29／30），两者差异无统计学意义（P＞0．05）。结论在CRC筛查中，MS‐HRM技术检测粪便中vimentin基因甲基化状态的诊断性能明显优于FOBT，具有潜在的应用价值。

Colorectal cancer screening by utilizing methylation-sensitive high-resolution melting curve analysis

Objective To assess the performance of the methylation‐sensitive high‐resolution melting curve analysis (MS‐HRM analysis) on the detection of the methylation in stool DNA for colorectal cancer screening .Methods Eighty‐two qualified stool samples were collected from 27 patients with colorectal cancer patients (CRC group) ,25 patients with advanced adenomas (AA group) ,and 30 healthy people (control group) .The methylation status of vimentin gene in all of the stool samples was detected by the MS‐HRM analysis on the LightCycler 480 platform .The fecal occult blood test (FOBT) was also used for the same samples . Results The positive rates of the MS‐HRM assay in the CRC group ,AA group ,and control group were 81 .5% (22/27) ,80 .0%(20/25) ,and 6 .7% (2/30) respectively .The positive rates of FOBT in the three groups were 37 .0% (10/27) ,12 .0% (3/25) and 3 .3% (1/30) respectively .The diagnostic sensitivity of the MS‐HRM assay for colorectal cancer and advanced adenomas (80 .8% , 42/52) was significantly higher than that of FOBT (25 .0% ,13/52)(P<0 .05) .No significant difference was found in the diagnos‐tic specificity between the MS‐HRM assay (93 .3% ,28/30) and the FOBT (96 .7% ,29/30) (P>0 .05) .Conclusion MS‐HRM performs better than FOBT and has great application potential in the detection of stool DNA methylation for colorectal cancer screening .