肝癌患者血浆ctDNA SCNM1甲基化水平检测及与临床预后评估价值研究

Plasma ctDNA SCNM1 Methylation Level and Its Clinical Prognostic Value in Hepatocellular Carcinoma Patients

目的 探讨肝细胞癌(hepatocellular carcinoma,HCC)患者血浆游离肿瘤DNA (circulating tumour DNA,ctDNA)中钠离子通道调节蛋白1(sodium channel modifier 1,SCNM1)甲基化水平与患者预后的关系。方法 选择2018年6月~2020年12月空军军医大学第一附属医院收治的67例肝细胞癌患者作为HCC组,同期健康人群50例作为对照组,收集对比患者临床资料。微滴式数字PCR(droplet digital PCR,ddPCR)检测血浆ctDNA SCNM1甲基化水平。比较不同组别间血清甲胎蛋白(alpha fetoprotein,AFP)、丙氨酸氨基转移酶(cereal third transaminase,ALT)、天冬氨酸氨基转移酶(aspartate transaminase,AST)、ctDNA水平和SCNM1甲基化比率的差异;比较不同SCNM1甲基化水平和不同预后患者临床病理特征差异,多因素COX回归分析肝细胞癌患者的预后影响因素;受试者工作特征(ROC)曲线分析SCNM1甲基化水平对预后判断的灵敏度和特异度。结果 HCC组血浆AFP水平[351.00(14.90,1 210.00)ng/ml]、ctDNA水平[57.65(15.79,171.90)ng/ml]、SCNM1甲基化水平[13.23%(4.36%,26.61%)]均高于对照组[2.90(2.20,5.10)ng/ml,15.75(12.85,21.07)ng/ml,4.69%(3.30%,6.68%)],差异具有统计学意义(Z=-7.18,-5.00,-4.77,均P <0.05);肿瘤病灶直径> 2cm,HCC远处转移患者的SCNM1甲基化呈现高水平(χ^(2)=5.01,38.85,均P <0.05);SCNM1甲基化检测高水平组患者中位生存期短于低水平组(13.31月vs. 24.44月),差异具有统计学意义(Log rankχ^(2)=4.141,P=0.04),SCNM1甲基化高水平是患者生存的独立影响因素(95%CI:2.449~62.716,P=0.002);SCNM1甲基化预测肝细胞癌患者病情进展的AUC(95%CI)为0.716(0.583~0.848),其敏感度和特异度分别为63.0%和81.1%。SCNM1甲基化、ctDNA联合AFP对肝细胞癌进展预测的AUC(95%CI)为0.747(0.618~0.875),敏感度和特异度分别为55.6%,91.9%。结论 SCNM1甲基化高水平提示HCC患者预后不良,是患者生存的独立影响因素,SCNM1甲基化、ctDNA,联合AFP检测可作为预后判断标志物。

Objective To investigate the relationship between prognostic value and methylated expression level of circulating tumour DNA(ctDNA)sodium channel modifier 1(SCNM1)in plasma of patients with hepatocellular carcinoma(HCC).Methods A total of 67 patients with confirmed HCC admitted to the First Affiliated Hospital of AFMU from June 2018 to December 2020 were selected as the research objects.At the same time,50 healthy volunteers were selected as the control group.Their clinical and pathological data were collected and compared.The methylation level of SCNM1 was detected by droplet digital PCR(ddPCR).The differences of alpha fetoprotein(AFP),cereal third transaminase(ALT),aspartate transaminase(AST),ctDNA,SCNM1 between HCC group and control group were analyzed.Multivariate COX regression risk model was performed to analyze the risk factors of HCC patients.Receiver operating characteristic(ROC)curve was used to analyze the sensitivity and specificity of SCNM1 methylation levels methylation levels.Results AFP[351.00(14.90,1210.00)ng/ml],ctDNA[57.65(15.79,171.90)ng/ml]and the methylated SCNM1 levels[13.23%(4.36%,26.61%)]in plasma in HCC group were higher than those in control group[2.90(2.20,5.10)ng/ml,15.75(12.85,21.07)ng/ml,4.69%(3.30%,6.68%)],and the differences were statistically significant(Z=-7.18,-5.00,-4.77,all P<0.05).High level of SCNM1 methylation was found in HCC patients with tumor lesion diameter>2cm and distant metastasis(χ^(2)=5.01,38.85,all P<0.05).The median survival was shorter in the high-methlated SCNM1 group than that in the low-methylated SCNM1 group(13.31 month vs 24.44 month)with significant difference(Log rankχ^(2)=4.141,P=0.04).High SCNM1 methylation level was independent risk factor for HCC patients survival(95%CI:2.449~62.716,P=0.002).The ROC curve showed prognostic value of increased methylated SCNM1 was 0.716(95%CI:0.583~0.848),and the sensitivity and specificity were 63.0%and 81.1%,respectively.When combined with plasma SCNM1 methylation level,ctDNA and AFP,the AUC(95%CI)of HCC progression was 0.747(0.618~0.875),and the sensitivity and specificity were 55.6%and 91.9%,respectively,which has potential application value for dynamic monitoring of liver cancer patients.Conclusion The high level of methylated SCNM1 in plasma indicates the HCC poor prognosis,and serves as an independent determinant of patient survival.Methylated SCNM1,ctDNA combined with AFP detection can serve as prognostic markers.