Huang Wenqing, Li Tong, Yang Wenli, Chai Xinjuan, Chen Kefei, Wei Ling, Duan Shuwang, Li Bo, Qin Yang
1 Department of Biochemistry and Molecular Biology, School of Preclinical and Forensic Medicine, West China Medical Center , Sichuan University, Chengdu, China .
2 Department of Dermatology, West China Hospital, Sichuan University , Chengdu, China .
Genet Test Mol Biomarkers. 2015 Jun;19(6):295-302. doi: 10.1089/gtmb.2014.0292. Epub 2015 Apr 29.
To explore whether the aberrant DNA methylation status in plasma could be used as a biomarker for hepatocellular carcinoma (HCC) screening among high-risk individuals.
The promoter methylation status of ELF, RASSF1A, p16, and GSTP1 was investigated by methylation-specific polymerase chain reaction (PCR) in 34 paired HCC and nontumor liver tissue from HCC patients and 10 tissues from patients with liver cirrhosis (LC). Plasma samples from 31 HCC patients, 10 LC patients as well as 7 patients with benign hepatic conditions were also collected and characterized using the same method.
Among liver specimens, HCC tissues displayed a significantly higher methylation frequency of each gene compared with nontumor tissue (p<0.05). Moreover, the frequency was much higher in tumor tissues than in nontumor tissue, when the data from two or three genes were combined (p=0.001 and p<0.001, respectively). Among plasma samples, either the frequency of at least one methylated gene (p<0.001) or the average number of methylated genes (p<0.05) demonstrated a stepwise increase in patients with benign lesions, LC, and HCC. Furthermore, when positive results, that is, plasma methylation status of at least one gene were combined with the elevated AFP400 level (serum alpha-fetoprotein [AFP] level at a cutoff of 400 ng/mL), the diagnostic sensitivity of HCC could increase to 93.55%.
These results suggested that the methylation of tumor suppressor genes may participate in the development and progression of HCC. Additionally, it may be useful to combine the plasma DNA methylation status of a panel of gene markers and the serum AFP for HCC screening.
探讨血浆中异常的DNA甲基化状态能否作为高危个体肝细胞癌（HCC）筛查的生物标志物。
采用甲基化特异性聚合酶链反应（PCR）检测34例HCC患者的配对HCC组织和非肿瘤肝组织以及10例肝硬化（LC）患者组织中ELF、RASSF1A、p16和GSTP1的启动子甲基化状态。还收集了31例HCC患者、10例LC患者以及7例肝脏良性疾病患者的血浆样本，并用相同方法进行分析。
在肝脏标本中，与非肿瘤组织相比，HCC组织中各基因的甲基化频率显著更高（p<0.05）。此外，当合并两个或三个基因的数据时，肿瘤组织中的频率比非肿瘤组织高得多（分别为p=0.001和p<０.001）。在血浆样本中，至少一个甲基化基因的频率（p<0.001）或甲基化基因的平均数量（p<0.05）在肝脏良性病变、LC和HCC患者中呈逐步上升趋势。此外，当阳性结果（即至少一个基因的血浆甲基化状态）与AFP400水平升高（血清甲胎蛋白[AFP]水平临界值为400 ng/mL）相结合时，HCC的诊断敏感性可提高至93.55%。
这些结果表明，抑癌基因的甲基化可能参与HCC的发生和发展。此外，将一组基因标志物的血浆DNA甲基化状态与血清AFP相结合用于HCC筛查可能是有用的。
