Research Article Promoter Methylation of SFRP3 Is Frequent in Hepatocellular Carcinoma Ya-Wen Lin, 1,2 Yu-Lueng Shih, 3 Gi-Shih Lien, 4 Fat-Moon Suk, 4 Chung-Bao Hsieh, 5 and Ming-De Yan 4 1 Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan 2 Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan 3 Division of Gastroenterology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan 4 Division of Gastroenterology, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan 5 Division of General Surgery, Department of Surgery, National Defense Medical Center, Tri-Service General Hospital, Taipei, Taiwan Correspondence should be addressed to Ming-De Yan; yanmd717@gmail.com Received 30 June 2013; Revised 1 October 2013; Accepted 22 October 2013; Published 21 January 2014 Academic Editor: Valeria Barresi Copyright © 2014 Ya-Wen Lin et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Oncogenic activation of the Wnt/-catenin signaling pathway is common in human cancers. Te secreted frizzled-related proteins (SFRPs) function as negative regulators of Wnt signaling and have important implications in carcinogenesis. Because there have been no reports about the role of SFRP3 in hepatocellular carcinoma (HCC), we investigated the level of methylation and transcription of SFRP3. Four HCC cell lines, 60 HCCs, 23 cirrhosis livers, 37 chronic hepatitis livers, and 30 control livers were prescreened for SFRP3 promoter methylation by methylation-specifc polymerase chain reaction (MS-PCR) and bisulfte sequencing. SFRP3 promoter methylation was observed in 100%, 60%, 39.1%, 16.2%, and 0% in HCC cell lines, primary HCCs, cirrhosis livers, chronic hepatitis livers, and control livers, respectively. Demethylation treatment with 5-aza-2  -deoxycytidine in HCC cells restored or increased the SFRP3 mRNA expression. We next used quantitative MS-PCR (QMSP) to analyze the methylation level of SFRP3 in 60 HCCs and their corresponding nontumor tissues. Methylation of SFRP3 promoter region in HCCs increased signifcantly compared with control tissues. Tere is a positive correlation between promoter hypermethylation and SFRP3 mRNA downregulation. Our data suggest that promoter hypermethylation of SFRP3 is a common event in HCCs and plays an important role in regulation of SFRP3 mRNA expression. 1. Introduction Hepatocellular carcinoma (HCC) is the most frequent pri- mary malignancy of the liver and accounts for as many as 1 million deaths annually worldwide [1–5]. Te major risk factors include chronic hepatitis B virus (HBV) infection, chronic hepatitis C virus (HCV) infection, environmental carcinogens such as afatoxin B1 (AFB1), alcoholic cirrhosis, and inherited genetic disorder such as hemochromatosis, Wilson disease, and tyrosinemia. Among them, HBV, HCV, and AFB1 are responsible for approximately 80% of all HCC [1, 2]. Research on molecular genetics and patho- genesis of HCC has become a hot spot in cancer study because of its scientifc merits and its clinical importance. Despite rapid expansion of information obtained from these researchers, the molecular mechanism of hepatocarcinogen- esis and molecular genetics of HCC remain elusive. Te Wnt/-catenin signaling pathway plays an important role in liver physiology and pathology by regulating a variety of crucial cellular events, including diferentiation, prolifer- ation, and survival [6–8]. The Wnt/-catenin pathway can be activated through mutations in CTNNB1 (encoding - catenin), AXIN1, and AXIN2 [6, 9] in human HCC. Te com- mon event is the stabilization of -catenin, which translocates into the nucleus and associates with the T-cell factor (TCF) family of transcription factors for efcient activation of Wnt target genes [10–17]. In addition to genetic mutations, Hindawi Publishing Corporation Disease Markers Volume 2014, Article ID 351863, 10 pages http://dx.doi.org/10.1155/2014/351863