Background & AimsAlpha-fetoprotein (AFP) is the most widely used serum biomarker for hepatocellular carcinoma (HCC), despite its limitations. As complementary biomarkers, protein induced by vitamin K absence (PIVKA-II), osteopontin (OPN), and Dickkopf-1 (DKK-1) have been proposed. This study aimed to perform a head-to-head comparison of the diagnostic performance of AFP, PIVKA-II, OPN and DKK-1 as single or in combination to seek the best biomarker or panel, and to investigate the clinical factors affecting their performance.MethodsUsing 401 stored plasma samples obtained from 208 HCC patients and 193 liver cirrhosis control patients, plasma AFP, PIVKA-II, OPN and DKK-1 levels were measured by ELISA, and receiver operating characteristic curve analyses were performed for each biomarker and for every combination of two to four markers.ResultsOf the four biomarkers, AFP showed the highest area under the curve (0.786). The sensitivity and specificity for each single biomarker was 62% and 90.2% (AFP>20 ng/mL), 51.0% and 91.2% (PIVKA-II>10 ng/mL), 46.2% and 80.3% (OPN>100 ng/mL), and 50.0% and 80.8% (DKK-1>500 pg/mL), respectively. Among the combinations of two biomarkers, AFP>20 ng/mL or DKK-1>500 pg/mL showed the best diagnostic performance (sensitivity 78.4%, specificity 72.5%). Triple or quadruple combination did not improve the diagnostic performance further. The patient’s age, etiology and tumor invasiveness of HCC affected the performance of each marker.ConclusionsAFP was the most useful single biomarker for HCC diagnosis, and the combined measurement of AFP and DKK-1 could maximize the diagnostic yield. Clinical decision should be based on the consideration of various factors affecting the diagnostic performance of each biomarker. Efforts to seek novel HCC biomarkers should be continued.

BackgroundCryptogenic hepatocellular carcinoma (HCC) is thought to arise due to non-alcoholic fatty liver disease (NAFLD). This study investigated the prevalence, clinical features, and outcomes of cryptogenic HCC and compared them with those of HCC related to hepatitis B virus infection (HBV-HCC), hepatitis C virus infection (HCV-HCC), and alcohol (ALC-HCC) in Korea.MethodsThe clinical features, treatment modalities, and survival data for 480 patients with HCC consecutively enrolled from January 2003 to June 2012 were analyzed. Computed tomography images were used to measure the visceral fat area (VFA) and liver-spleen density ratio.ResultsCryptogenic HCC accounted for 6.8% of all HCC cases, whereas HBV-HCC, HCV-HCC, and ALC-HCC accounted for 62.7%, 13.5%, and 10.7% of HCC cases, respectively. The cryptogenic HCC group was characterized by older age, a low proportion of male patients, a high proportion of patients with metabolic syndrome or single nodular presentation, and a low proportion of patients with portal vein invasion compared to the viral-HCC and ALC-HCC groups. However, Child Pugh classes, tumor stages, and overall survival rates of cryptogenic HCC patients were similar to those of patients with HCC of other etiologies. VFA in cryptogenic HCC patients was significantly higher than that in viral-HCC patients, but similar to that in ALC-HCC patients. The liver-spleen density ratio did not vary according to HCC etiology.ConclusionsCryptogenic HCC accounts for approximately 7% of HCC cases in Korea, associated with an older age at diagnosis, more frequent occurrence of metabolic syndrome, and less aggressive tumor characteristics, but similar survival compared to viral-HCC or ALC-HCC. Based on VFA and the liver-to-spleen density ratio, cryptogenic HCC may be burnt-out NAFLD in which visceral fat remains but liver fat is depleted.

is a principal investigator in a clinical trial supported by Chong Kun Dang pharm. and is participating as an investigator in clinical trials supported by Eisai and Celltrion. Author contributions: Jin-Wook Kim: designed the research study, collected analyzed the data, and wrote the paper; Ingyoon Ha and Jung Wha Chung collected and analyzed the data and wrote the paper; Eun Sun Jang and Sook-Hyang Jeong analyzed the data and wrote the paper.

Small interfering RNA (siRNA) induces transcriptional gene silencing (TGS) in plant and animal cells. RNA dependent DNA methylation (RdDM) accounts for TGS in plants, but it is unclear whether siRNA induces RdDM in mammalian cells. To determine whether stable expression of short hairpin siRNA (shRNA) induces DNA methylation in mammalian cells, we transduced rat hepatic stellate SBC10 cells with lentiviral vectors which encode an U6 promoter-driven shRNA expression cassette homologous to the transforming growth factor-beta receptor (TGFbetaRII) promoter region. Sequencing analysis of bisulfite-modified genomic DNA showed the methylation of cytosine residues both in CpG dinucleotides and non-CpG sites around the target region of the TGFbetaRII promoter in SBC10 cells transduced with the promoter-targeting lentiviral vector. In these cells, real-time RT-PCR showed a decrease in TGFbetaRII mRNA levels which were reversed by treatment with 5-aza-2-deoxycytidine. Our results demonstrate that recombinant lentivirus-mediated shRNA delivery resulted in the methylation of the homologous promoter area in mammalian cells, and this approach may be used as a tool for transcriptional gene silencing by epigenetic modification of mammalian cell promoters.