Awad Ahmed M, Ragab Wafaa S, Degheidy Nourhan, Ooda Said Ahmed
Chemical Pathology Department, Medical Research Institute, Alexandria University, Egypt.
Experimental and Clinical Internal Medicine Department, Medical Research Institute, Alexandria University, Egypt.
Int J Genomics. 2020 Oct 2;2020:1769735. doi: 10.1155/2020/1769735. eCollection 2020.
DNA methylation is an epigenetic mechanism used by cells to control gene expression. DNA methylation is a commonly used epigenetic signaling tool that can hold genes in the "off" position. Chronic infection with hepatitis C virus (HCV) is considered a major risk for chronic liver impairment. It is the most common leading cause of HCC. The present work is aimed at studying whole genome 5'-methylcytosine levels in cirrhotic HCV-infected Egyptian patients. In the present study, 120 Egyptian adults were included. They were divided into two groups: group І (40 apparently healthy control subjects) and group ІІ (80 HCV-infected patients). Furthermore, group II was subdivided into 2 subgroups according to the presence of HCC in HCV-infected subjects. To all studied subjects, the level of 5-mC% was measured in peripheral blood. In the present study, the median of 5'-methylcytosine% in the control group (group I) was 2.5, in the HCV group (group IIa) was 2.45, and in the HCC group (group II b) was 2.25. A stepwise decrease in 5'-methylcytosine% from the control (group I) toward HCC (group IIb) was observed, taking into consideration that the stepwise global hypomethylation was not statistically significant ( = 0.811). There was a negative correlation between ALT and 5'-methylcytosine% ( = -0.029). From this study, we can conclude that global DNA 5'-methylcytosine% does not differ in HCV-infected cirrhotic patients and HCC patients when compared to normal controls. Consecutively, we had concluded that there is no impact of 5'-methylcytosine% on the development of liver cirrhosis or HCC. Moreover, the negative correlation between 5'-methylcytosine% and serum ALT level denotes a trend of decrease in 5'-methylcytosine% with more liver damage.
DNA甲基化是细胞用于控制基因表达的一种表观遗传机制。DNA甲基化是一种常用的表观遗传信号工具，可使基因处于“关闭”状态。丙型肝炎病毒（HCV）慢性感染被认为是慢性肝脏损害的主要风险因素。它是肝癌最常见的主要病因。目前的工作旨在研究肝硬化HCV感染的埃及患者的全基因组5'-甲基胞嘧啶水平。在本研究中，纳入了120名埃及成年人。他们被分为两组：第一组（40名明显健康的对照受试者）和第二组（80名HCV感染患者）。此外，根据HCV感染受试者中肝癌的存在情况，将第二组再细分为2个亚组。对所有研究对象，测量外周血中5-mC%的水平。在本研究中，对照组（第一组）中5'-甲基胞嘧啶%的中位数为2.5，HCV组（第二组a）为2.45，肝癌组（第二组b）为2.25。观察到从对照组（第一组）到肝癌组（第二组b）5'-甲基胞嘧啶%呈逐步下降趋势，考虑到逐步的全基因组低甲基化无统计学意义（P = 0.811）。谷丙转氨酶（ALT）与5'-甲基胞嘧啶%之间存在负相关（P = -0.029）。从本研究中，我们可以得出结论，与正常对照组相比，HCV感染的肝硬化患者和肝癌患者的全基因组DNA 5'-甲基胞嘧啶%没有差异。相应地，我们得出结论，5'-甲基胞嘧啶%对肝硬化或肝癌的发生没有影响。此外，5'-甲基胞嘧啶%与血清ALT水平之间的负相关表明随着肝脏损伤加重，5'-甲基胞嘧啶%有下降趋势。
