Prospective Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Feb 18, 2016; 8(5): 301-306
Published online Feb 18, 2016. doi: 10.4254/wjh.v8.i5.301
Blood DNA methylation markers in prospectively identified hepatocellular carcinoma cases and controls from Taiwan
Hui-Chen Wu, Jing Shen, Hwai-I Yang, Wei-Yann Tsai, Chien-Jen Chen, Regina M Santella
Hui-Chen Wu, Jing Shen, Regina M Santella, Department of Environmental Health Sciences, Mailman School of Public Health of Columbia University, New York, NY 10032, United States
Hwai-I Yang, Chien-Jen Chen, Genomics Research Center, Academia Sinica, Taipei 11529, Taiwan
Hwai-I Yang, Graduate Institute of Clinical Medical Science, China Medical University, Taichung 40402, Taiwan
Hwai-I Yang, Molecular and Genomic Epidemiology Center, China Medical University Hospital, Taichung 40402, Taiwan
Wei-Yann Tsai, Departments of Biostatistics, Mailman School of Public Health of Columbia University, New York, NY 10032, United States
Wei-Yann Tsai, Department of Statistics, National Chen Kung University, Tainan 70101, Taiwan
Chien-Jen Chen, Graduate Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei 10617, Taiwan
Regina M Santella, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032, United States
Author contributions: Wu HC analyzed the data and drafted the manuscript; Shen J generated the 450k array data and helped to select the genes to evaluate; Yang HI coordinated the followup of the cohort; Tsai WY reviewed the data analysis; Chen CJ designed the cohort and supervises all projects using samples; Santella RM designed the study; all authors reviewed the manuscript.
Supported by National Institutes of Health grants, RO1ES005116 (Santella RM) and P30ES009089 (Santella RM).
Institutional review board statement: The study was reviewed and approved by the Columbia University Medical Center Institutional Review Board.
Informed consent statement: All study participants provided informed written consent prior to study enrollment.
Conflict-of-interest statement: There are no conflicts for all authors.
Data sharing statement: Detailed data is available from the corresponding author.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Hui-Chen Wu, Department of Environmental Health Sciences, Mailman School of Public Health of Columbia University, 650 West 168th St, New York, NY 10032, United States. hw2057@columbia.edu
Telephone: +1-212-3058158 Fax: +1-212-3053857
Received: March 14, 2015
Peer-review started: March 16, 2015
First decision: April 10, 2015
Revised: January 8, 2016
Accepted: January 21, 2016
Article in press: January 22, 2016
Published online: February 18, 2016
Processing time: 338 Days and 1.1 Hours
Abstract

AIM: To determine if gene-specific DNA methylation in prospectively collected blood samples is associated with later development of hepatocellular carcinoma (HCC).

METHODS: Comparing genome-wide DNA methylation profiles using Illumina Human methylation 450K arrays, we previously identified a list of loci that were differentially methylated between tumor and adjacent nontumor tissues. To examine if dysregulation of DNA methylation patterns observed in tumor tissues can be detected in white blood cell (WBC) DNA, we conducted a prospective case-control study nested within a community-based cancer screening cohort in Taiwan with 16 years of follow up. We measured methylation levels in ninety-six loci that were aberrant in DNA methylation in HCC tumor tissues compared to adjacent tissues. Baseline WBC DNA from 159 HCC cases and 312 matched controls were bisulfite treated and assayed by Illumina BeadArray. We used the χ2 test for categorical variables and student’s t-test for continuous variables to assess the difference in selected characteristics between cases and controls. To estimate associations with HCC risk, we used conditional logistic regression models stratified on the matching factors to calculate odds ratios (OR) and 95%CI.

RESULTS: We found that high methylation level in cg10272601 in WNK2 was associated with increased risk of HCC, with an OR of 1.91 (95%CI: 1.27-2.86). High methylation levels in both cg12680131 in TPO and cg22511877 in MYT1L, however, were associated with decreased risk. The ORs (95%CI) were 0.59 (0.39-0.87) and 0.50 (0.33-0.77), respectively, for those with methylation levels of cg12680131 and cg22511877 above the median compared with those with levels below the median. These associations were still statistically significant in multivariable conditional logistic regression models after adjusting for hepatitis B virus infection and alcohol consumption.

CONCLUSION: These findings support the measurement of methylation markers in WBC DNA as biomarkers of HCC susceptibility but should be replicated in additional prospective studies.

Keywords: DNA methylation; Epigenetics; Hepatitis B virus; Hepatocellular carcinoma; White blood cell DNA

Core tip: Hepatocellular carcinoma (HCC) is a highly fatal disease thus, the identification of biomarkers that could predict risk for development could enhance screening/early detection and prognosis. DNA methylation alterations are well established in HCC but whether changes in DNA methylation in white blood cells (WBC) are associated with increased risk of developing HCC is unknown. Taking advantage of a cancer screening program in Taiwan, we measured baseline WBC DNA methylation in prospectively collected blood samples at 96 CpG sites that were identified as differentially methylated in HCC tumors compared to adjacent tissues. Three were significantly associated with later development of HCC suggesting potential utility as a marker of risk.