Publications by authors named "Ryosuke Muroyama"

34 Publications

Acquisition of mesenchymal-like phenotypes and overproduction of angiogenic factors in lenvatinib-resistant hepatocellular carcinoma cells.

Biochem Biophys Res Commun 2021 Apr 3;549:171-178. Epub 2021 Mar 3.

Department of Gastroenterology, Graduate School of Medicine, Chiba University, Chiba, Japan.

Lenvatinib is one of the first-line drugs for patients with advanced hepatocellular carcinoma (HCC) and widely used around the world. However, the mechanisms underlying resistance to lenvatinib remain unclear. In this study, we conducted characteristic analyses of lenvatinib-resistant HCC cells. Lenvatinib-resistant HCC cell lines were established by exposure to serially escalated doses of lenvatinib over 2 months. The biological characteristics of these cells were examined by in vitro assays. To investigate the cytokine profile of lenvatinib-resistant HCC cells, the supernatant derived from lenvatinib-resistant Huh7 cells was subjected to nitrocellulose membrane-based sandwich immunoassay. Both activation of the MAPK/MEK/ERK signaling pathway and upregulation of epithelial mesenchymal transition markers were observed in lenvatinib-resistant cells. Concordant with these findings, proliferation and invasion abilities were enhanced in these cells compared with control cells. Screening of a cytokine array spotted with 105 different antibodies to human cytokines enabled us to identify 16 upregulated cytokines in lenvatinib-resistant cells. Among them, 3 angiogenic cytokines: vascular endothelial growth factor (VEGF), platelet-derived growth factor-AA (PDGF-AA), and angiogenin, were increased significantly. Conditioned medium from lenvatinib-resistant cells accelerated tube formation of human umbilical vein cells. In conclusion, lenvatinib-resistant HCC cells were characterized by enhanced proliferation and invasion abilities. These findings might contribute to the establishment of new combination therapies with lenvatinib.
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http://dx.doi.org/10.1016/j.bbrc.2021.02.097DOI Listing
April 2021

The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma.

Sci Rep 2021 Mar 5;11(1):5303. Epub 2021 Mar 5.

Department of Gastroenterology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan.

FGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19 (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19 (n = 105) patients, there were no significant differences between FGF19 (n = 21) and FGF19 (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.
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http://dx.doi.org/10.1038/s41598-021-84117-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7935880PMC
March 2021

Interferon-γ induced PD-L1 expression and soluble PD-L1 production in gastric cancer.

Oncol Lett 2020 Sep 19;20(3):2161-2168. Epub 2020 Jun 19.

Department of Gastroenterology, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan.

Programmed death-ligand 1 (PD-L1) plays an essential role in tumor cell escape from anti-tumor immunity in various types of cancer, including gastric cancer (GC). The present study investigated the intracellular and membrane-bound expression of PD-L1 in the GC cell lines MKN1, MKN74, KATO III and OCUM-1. Furthermore, soluble PD-L1 (sPD-L1) level in the supernatant of GC cells and the serum of patients with GC and healthy controls was determined by ELISA. Interferon (IFN)-γ treatment of cells resulted in increased cytoplasmic expression of PD-L1 in GC cells in a dose-dependent manner, except for MKN74 cells; however, there was no association between tumor necrosis factor-α treatment and enhanced PD-L1 expression. Concordant with these findings, results from flow cytometry analysis demonstrated that membrane-bound PD-L1 expression was also increased following GC cell treatment with IFN-γ in a dose-dependent manner. In addition, significant sPD-L1 overproduction was observed only in the culture supernatant of OCUM-1 cells. Serum level of sPD-L1 was significantly increased in patients with GC, in particular in stage IV patients, compared with healthy controls. In conclusion, the present study demonstrated that IFN-γ treatment increased the intracellular and membrane-bound PD-L1 expression in GC cells. In addition, sPD-L1 was detected not only in the supernatant of GC cells but also in the serum of patients with GC. Further investigation on the underlying mechanism of regulation of PD-L1 expression and sPD-L1 production is required.
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http://dx.doi.org/10.3892/ol.2020.11757DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7400993PMC
September 2020

Leukotriene receptor antagonists enhance HCC treatment efficacy by inhibiting ADAMs and suppressing MICA shedding.

Cancer Immunol Immunother 2021 Jan 18;70(1):203-213. Epub 2020 Jul 18.

Division of Gastroenterology, Department of Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8666, Japan.

In our previous genome-wide association study, we demonstrated the association between MHC class I-related chain A (MICA) and hepatocellular carcinoma (HCC) development in patients with chronic hepatitis C. Increasing membrane-bound MICA (mMICA) in cancer cells by reducing MICA sheddases facilitates natural killer (NK) cell-mediated cytotoxicity. Our recent study clarified that A disintegrin and metalloproteases (ADAM), including ADAM9, are MICA sheddases in HCC, and that the suppression of ADAMs increases mMICA, demonstrating the rationality of mMICA-NK targeted therapy. Furthermore, we showed that regorafenib suppresses ADAM9 transcriptionally and translationally. A library of FDA-approved drugs was screened for more efficient inhibitors of ADAM9. Flow cytometry evaluation of the expression of mMICA after treatment with various candidate drugs identified leukotriene receptor antagonists as potential ADAM9 inhibitors. Furthermore, leukotriene receptor antagonists alone or in combination with regorafenib upregulated mMICA, which was in turn downregulated by leukotriene C4 and D4 via ADAM9 function. Our study demonstrates that leukotriene receptor antagonists could be developed as novel drugs for immunological control and suppression of ADAM9 in HCC. Further, leukotriene receptor antagonists should be explored as combination therapy partners with conventional multi-kinase inhibitors for developing therapeutic strategies with enhanced efficacies for HCC management and treatment.
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http://dx.doi.org/10.1007/s00262-020-02660-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7838147PMC
January 2021

A Novel Role of Interleukin 13 Receptor alpha2 in Perineural Invasion and its Association with Poor Prognosis of Patients with Pancreatic Ductal Adenocarcinoma.

Cancers (Basel) 2020 May 20;12(5). Epub 2020 May 20.

Tumor Vaccines and Biotechnology Branch, Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA.

Perineural invasion (PNI) is one of the major pathological characteristics of pancreatic ductal adeno-carcinoma (PDAC), which is mediated by invading cancer cells into nerve cells. Herein, we identify the overexpression of Interleukin-13 Receptor alpha2 (IL-13Rα2) in the PNI from 236 PDAC samples by studying its expression at the protein levels by immunohistochemistry (IHC) and the RNA level by in situ hybridization (ISH). We observe that ≥75% samples overexpressed IL-13Rα2 by IHC and ISH in grade 2 and 3 tumors, while ≥64% stage II and III tumors overexpressed IL-13Rα2 (≥2+). Interestingly, ≥36 % peripancreatic neural plexus (PL) and ≥70% nerve endings (Ne) among PNI in PDAC samples showed higher levels of IL-13Rα2 (≥2+). IL-13Rα2 +ve PL and Ne subjects survived significantly less than IL-13Rα2 -ve subjects, suggesting that IL-13Rα2 may have a unique role as a biomarker of PNI-aggressiveness. Importantly, IL-13Rα2 may be a therapeutic target for intervention, which might not only prolong patient survival but also help alleviate pain attributed to perineural invasion. Our study uncovers a novel role of IL-13Rα2 in PNI as a key factor of the disease severity, thus revealing a therapeutically targetable option for PDAC and to facilitate PNI-associated pain management.
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http://dx.doi.org/10.3390/cancers12051294DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7281570PMC
May 2020

Serum fibroblast growth factor 19 serves as a potential novel biomarker for hepatocellular carcinoma.

BMC Cancer 2019 Nov 12;19(1):1088. Epub 2019 Nov 12.

Department of Gastroenterology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan.

Background: Abnormal autocrine fibroblast growth factor 19 (FGF19) production has been observed in several types of cancers, including hepatocellular carcinoma (HCC). In this study, we investigated the potential of serum FGF19 as a novel tumor marker of HCC based on a sandwich enzyme-linked immunosorbent assay (ELISA).

Methods: The serum FGF19 levels of 304 patients with HCC was measured by ELISA. The serum levels of existing markers, including alpha-fetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) were determined by chemiluminescence enzyme immunoassay. Both diagnostic value of FGF19 and its changes after curative ablation therapy was further examined.

Results: The median FGF19 levels in controls, chronic liver disease patients, and primary HCC patients, were 78.8 pg/mL, 100.1 pg/mL, and 214.5 pg/mL, respectively. The subsequent receiver operating characteristic curves (ROC) successfully determined an optimal cut-off value of 200.0 pg/mL. The area under the ROC curve (AUC) of FGF19 for HCC detection was comparable to those of AFP and DCP. Of importance, FGF19 showed higher sensitivity for the detection of small HCC (solitary cancer with diameter < 20 mm) than those of existing markers. In addition, 43 out of 79 cases (54.4%) with normal AFP and DCP (so-called "double negative HCC") exhibited serum FGF19 level ≥ 200 pg/mL. In 45 HCC patients treated with curative ablation therapy, serum FGF19 levels changed from 257.4 pg/mL to 112.0 pg/mL after the treatment.

Conclusion: Our findings reveal that FGF19 can be a potential novel biomarker for HCC. Although FGF19 is not necessarily a substitute for existing markers, it may help improve the prognosis in HCC patients owing to its resourceful use in various aspects of HCC management and treatment.
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http://dx.doi.org/10.1186/s12885-019-6322-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6849282PMC
November 2019

CD4 T cells from patients with primary biliary cholangitis show T cell activation and differentially expressed T-cell receptor repertoires.

Hepatol Res 2019 Jun 26;49(6):653-662. Epub 2019 Feb 26.

Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan.

Aim: Primary biliary cholangitis (PBC) is an autoimmune liver disease with unknown pathogenesis. In PBC, activation of T-cell receptor (TCR) signaling is associated with inflammatory cytokine production through N-Ras upregulation. Although the CD4 T cell TCR repertoire could be associated with PBC pathogenesis, it has not been evaluated. Thus, we analyzed the PBC-CD4 T cell TCR repertoire using next generation sequencing (NGS).

Methods: Four PBC patients (one treatment-naïve and three receiving ursodeoxycholic acid) and three healthy individuals were enrolled. NRAS expression in CD4 T cells was assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). N-Ras dynamics in CD4 T cells were assessed by qRT-PCR and GTP-N-Ras activation assay. The TCR α- (TRA) and β-chain (TRB) repertoires on CD4 T cells were analyzed by NGS and profiled using hierarchical analysis. Motif analysis was undertaken to elucidate the structure of PBC-specific TCRs.

Results: NRAS was upregulated in PBC relative to control CD4 T cells (P < 0.05), and N-Ras enhanced T cell activation in CD4 T cells. Among 2668 TRAs and 841 TRBs, 20 and 11, respectively, were differentially expressed in PBC compared to that in controls (P < 0.05, fold-change >2). Among them, TRAV29/J22, TRBV6-5/J2-6, and TRBV10-1/J2-1 were expressed in PBC but the expression was negligible in the controls, with more mature and longer forms observed in PBC-CD4 T cells.

Conclusions: N-Ras was upregulated in PBC-CD4 T cells, and it enhanced TCR activation, indicating that PBC-CD4 T cells were activated by N-Ras upregulation with differentially expressed TCR repertoires on their surfaces.
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http://dx.doi.org/10.1111/hepr.13318DOI Listing
June 2019

Enzymatic inhibition of MICA sheddase ADAM17 by lomofungin in hepatocellular carcinoma cells.

Int J Cancer 2018 11 22;143(10):2575-2583. Epub 2018 Sep 22.

Division of Advanced Genome Medicine, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

In our previous study on hepatocellular carcinoma (HCC) susceptibility genes in chronic hepatitis patients, we identified the MHC class I polypeptide-related sequence A (MICA). Natural killer cells eliminate various cancer cells, including HCC, by suppressing MICA shedding. Therefore, we investigated MICA sheddases and inhibitors for HCC immunotherapy. In this study, HepG2, PLC/PRF/5, and Hep3B were treated with the siRNA of a disintegrin and metalloproteases (ADAMs) and matrix metalloproteases to measure the concentration of soluble MICA (sMICA) by ELISA to detect the therapeutic target. Furthermore, an FDA-approved drug library was tested for the enzymatic inhibition of the targeted enzyme in an in vitro drug screening assay system. ADAM17 knockdown reduced sMICA levels and increased membrane-bound MICA (mMICA) expression in HCC cells. In an in vitro drug screen using an FDA-approved drug library, lomofungin, an antifungal drug, was found to strongly decrease ADAM17 activity. In HCC cells, mMICA expression was induced and sMICA production was inhibited in a dose-dependent manner. These effects were cancelled upon ADAM17 knockdown, suggesting that lomofungin targeted ADAM17. Analysis of lomofungin analogs revealed the responsible functional groups. In summary, we suggest lomofungin to be an attractive agent for the immunological control of HCC, via the suppression of ADAM17.
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http://dx.doi.org/10.1002/ijc.31615DOI Listing
November 2018

Predominance of regorafenib over sorafenib: Restoration of membrane-bound MICA in hepatocellular carcinoma cells.

J Gastroenterol Hepatol 2018 May 6;33(5):1075-1081. Epub 2018 Feb 6.

Division of Advanced Genome Medicine, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Background And Aim: The multi-kinase inhibitor regorafenib (REG) was recently demonstrated to be effective in patients with sorafenib (SOR)-resistant hepatocellular carcinoma (HCC). Interestingly, SOR is known to enhance the accumulation of membrane-bound MHC class I polypeptide-related sequence A (mMICA) in HCC cells and to block the production of soluble MICA (sMICA), an immunological decoy. In addition, MICA is associated with HCC in patients with chronic hepatitis C. We have now compared the impact of REG and SOR on MICA in HCC cells, as well as the immunotherapeutic implications thereof.

Methods: HepG2 and PLC/PRF/5 cells were exposed to REG and SOR, and levels of sMICA and mMICA were measured by ELISA and flow cytometry, respectively. The drugs were also tested in vitro for inhibitory activity against recombinant human A disintegrin and metalloprotease 9 (ADAM9), a sheddase that releases MICA from the membrane.

Results: To a greater extent than SOR, but without marked difference in cytotoxicity, REG significantly suppressed mRNA and protein expression of ADAM9 and ADAM10, thereby decreasing production of sMICA and boosting accumulation of mMICA. Accumulation of mMICA in response to REG was reversed by siRNA against ADAM9. However, the drugs did not inhibit the enzymatic activity of ADAM9 in vitro.

Conclusions: The clinical superiority of REG over SOR is partially attributable to reduced MICA shedding via transcriptional suppression of ADAM9 and ADAM10.
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http://dx.doi.org/10.1111/jgh.14029DOI Listing
May 2018

miR-425 regulates inflammatory cytokine production in CD4 T cells via N-Ras upregulation in primary biliary cholangitis.

J Hepatol 2017 06 10;66(6):1223-1230. Epub 2017 Feb 10.

Department of Gastroenterology and Hepatology, The Jikei University School of Medicine, Tokyo, Japan; Sanno Medical Center, Sanno Hospital, International University of Health and Welfare, Tokyo, Japan.

Background & Aims: Primary biliary cholangitis (PBC) is an autoimmune liver disease of unknown pathogenesis. Consequently, therapeutic targets for PBC have yet to be identified. CD4 T cells play a pivotal role in immunological dysfunction observed in PBC, and therefore, microRNA (miRNA) and mRNA expression were analysed in CD4 T cells, to investigate PBC pathogenesis and identify novel therapeutic targets.

Methods: Integral miRNA and mRNA analysis of 14 PBC patients and ten healthy controls was carried out using microarray and quantitative real-time polymerase chain reaction (qRT-PCR), with gene set enrichment analysis. The functional analyses of miRNA were then assessed using reporter and miRNA-overexpression assays.

Results: The integral analysis of miRNA and mRNA identified four significantly downregulated miRNAs (miR-181a, -181b, -374b, and -425) related to the T cell receptor (TCR) signalling pathway in CD4 T cells of PBC. N-Ras, a regulator of the TCR signalling pathway, was found to be targeted by all four identified miRNAs. In addition, in vitro assays confirmed that decreased miR-425 strongly induced inflammatory cytokines (interleukin [IL]-2 and interferon [IFN]-γ) via N-Ras upregulation in the TCR signalling pathway.

Conclusion: The decreased expression of four miRNAs that dysregulate TCR signalling in PBC CD4 T cells was identified. miR-425 was demonstrated as an inflammatory regulator of PBC via N-Ras upregulation. Therefore, the restoration of decreased miR-425 or the suppression of N-Ras may be a promising immunotherapeutic strategy against PBC.

Lay Summary: Primary biliary cholangitis (PBC) is an autoimmune liver disease, but the causes are unknown. MicroRNAs are molecules known to regulate biological signals. In this study, four microRNAs were identified as being decreased in PBC patients, leading to activation of T cell receptor signalling pathways, involved in inflammation. One particular target, N-Ras, could be an attractive and novel immunotherapeutic option for PBC.

Transcript Profiling: Microarray data are deposited in GEO (GEO accession: GSE93172).
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http://dx.doi.org/10.1016/j.jhep.2017.02.002DOI Listing
June 2017

Novel chemoimmunotherapeutic strategy for hepatocellular carcinoma based on a genome-wide association study.

Sci Rep 2016 12 2;6:38407. Epub 2016 Dec 2.

The Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan.

Pharmacotherapeutic options are limited for hepatocellular carcinoma (HCC). Recently, we identified the anti-tumor ligand MHC class I polypeptide-related sequence A (MICA) gene as a susceptibility gene for hepatitis C virus-induced HCC in a genome-wide association study (GWAS). To prove the concept of HCC immunotherapy based on the results of a GWAS, in the present study, we searched for drugs that could restore MICA expression. A screen of the FDA-approved drug library identified the anti-cancer agent vorinostat as the strongest hit, suggesting histone deacetylase inhibitors (HDACis) as potent candidates. Indeed, the HDACi-induced expression of MICA specific to HCC cells enhanced natural killer (NK) cell-mediated cytotoxicity in co-culture, which was further reinforced by treatment with an inhibitor of MICA sheddase. Similarly augmented anti-tumor activity of NK cells via NK group 2D was observed in vivo. Metabolomics analysis revealed HDACi-mediated alterations in energy supply and stresses for MICA induction and HCC inhibition, providing a mechanism for the chemoimmunotherapeutic actions. These data are indicative of promising strategies for selective HCC innate immunotherapy.
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http://dx.doi.org/10.1038/srep38407DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5133582PMC
December 2016

[Development status of DAA against hepatitis C].

Nihon Rinsho 2015 Dec;73 Suppl 9:262-8

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December 2015

The characteristic changes in hepatitis B virus x region for hepatocellular carcinoma: a comprehensive analysis based on global data.

PLoS One 2015 5;10(5):e0125555. Epub 2015 May 5.

Division of advanced genome medicine, Advanced clinical research center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Objectives: Mutations in hepatitis B virus (HBV) X region (HBx) play important roles in hepatocarcinogenesis while the results remain controversial. We sought to clarify potential hepatocellular carcinoma (HCC)-characteristic mutations in HBx from HBV genotype C-infected patients and the distribution of those mutations in different disease phases and genotypes.

Methods: HBx sequences downloaded from an online global HBV database were screened and then classified into Non-HCC or HCC group by diagnosis information. Patients' data of patient age, gender, country or area, and viral genotype were also extracted. Logistic regression was performed to evaluate the effects of mutations on HCC risk.

Results: 1) Full length HBx sequences (HCC: 161; Non-HCC: 954) originated from 1115 human sera across 29 countries/areas were extracted from the downloaded 5956 HBx sequences. Genotype C occupied 40.6% of Non-HCC (387/954) and 89.4% of HCC (144/161). 2) Sixteen nucleotide positions showed significantly different distributions between genotype C HCC and Non-HCC groups. 3) Logistic regression showed that mutations A1383C (OR: 2.32, 95% CI: 1.34-4.01), R1479C/T (OR: 1.96, 95% CI: 1.05-3.64; OR: 5.15, 95% CI: 2.53-10.48), C1485T (OR: 2.40, 95% CI: 1.41-4.08), C1631T (OR: 4.09, 95% CI: 1.41-11.85), C1653T (OR: 2.58, 95% CI: 1.59-4.19), G1719T (OR: 2.11, 95% CI: 1.19-3.73), and T1800C (OR: 23.59, 95% CI: 2.25-247.65) were independent risk factors for genotype C HBV-related HCC, presenting different trends among individual disease phases. 4) Several genotype C HCC risk mutations pre-existed, even as major types, in early disease phases with other genotypes.

Conclusions: Mutations associated with HCC risk were mainly located in HBx transactivation domain, viral promoter, protein/miRNA binding sites, and the area for immune epitopes. Furthermore, the signatures of these mutations were unique to disease phases leading to HCC, suggesting molecular counteractions between the virus and host during hepatocarcinogenesis.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0125555PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420286PMC
February 2016

[Hepatitis C virus induced hepatocellular carcinoma associated genes].

Nihon Rinsho 2015 Feb;73(2):333-8

Hepatitis C virus (HCV) infection is a major risk factor for developing hepatocellular carcinoma (HCC). The host genetic factors involved in the development of HCC in patients with HCV infection were investigated. To identify the genetic susceptibility factors for HCV-induced HCC, genome wide association studies (GWAS) were conducted in HCV-induced HCC cases and controls of Japanese origin. Single nucleotide polymorphisms (SNPs) which showed possible association in the GWAS were further genotyped using different cohorts. By these analyses, MICA and DEPDC5 SNPs were found to be strongly associated with HCV-induced HCC. These results highlight the importance of MICA and DEPDC5 genetic variations not only as predictive biomarkers for HCV-induced HCC but also as therapeutic targets against hepatocarcinogenesis or HCC.
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February 2015

The flavonoid apigenin inhibits hepatitis C virus replication by decreasing mature microRNA122 levels.

Virology 2014 Aug 14;462-463:42-8. Epub 2014 Jun 14.

Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 5-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.

Despite recent progress in the development of direct-acting antivirals against hepatitis C virus (HCV), chronic HCV infection remains an important health burden worldwide. MicroRNA122 (miR122), a liver-specific microRNA (miRNA), positively regulates HCV replication, and systemic application of antisense oligonucleotides against miR122 led to the long-lasting suppression of HCV viremia in human clinical trials. Here, we report that apigenin, a flavonoid and an inhibitor of maturation of a subset of miRNAs, inhibits HCV replication in vitro. Apigenin decreased the expression levels of mature miR122 without significantly affecting cell growth. Because supplementation of synthesized miR122 oligonucleotides or overexpression of constitutively active TRBP blocked these effects, the inhibitory effects of apigenin on HCV replication seemed to be dependent on the reduction of mature miR122 expression levels through inhibition of TRBP phosphorylation. Thus, apigenin intake, either through regular diet or supplements, may decrease HCV replication in chronically infected patients.
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http://dx.doi.org/10.1016/j.virol.2014.05.024DOI Listing
August 2014

Specific delivery of microRNA93 into HBV-replicating hepatocytes downregulates protein expression of liver cancer susceptible gene MICA.

Oncotarget 2014 Jul;5(14):5581-90

Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.

Chronic hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC). To date, the lack of efficient in vitro systems supporting HBV infection and replication has been a major limitation of HBV research. Although primary human hepatocytes support the complete HBV life cycle, their limited availability and difficulties with gene transduction remain problematic. Here, we used human primary hepatocytes isolated from humanized chimeric uPA/SCID mice as efficient sources. These hepatocytes supported HBV replication in vitro. Based on analyses of mRNA and microRNA (miRNA) expression levels in HBV-infected hepatocytes, miRNA93 was significantly downregulated during HBV infection. MiRNA93 is critical for regulating the expression levels of MICA protein, which is a determinant for HBV-induced HCC susceptibility. Exogenous addition of miRNA93 in HBV-infected hepatocytes using bionanocapsules consisted of HBV envelope L proteins restored MICA protein expression levels in the supernatant. These results suggest that the rescued suppression of soluble MICA protein levels by miRNA93 targeted to HBV-infected hepatocytes using bionanocapsules may be useful for the prevention of HBV-induced HCC by altering deregulated miRNA93 expression.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4170619PMC
http://dx.doi.org/10.18632/oncotarget.2143DOI Listing
July 2014

Impact of PNPLA3 polymorphisms on the development of hepatocellular carcinoma in patients with chronic hepatitis C virus infection.

Hepatol Res 2014 Oct 8;44(10):E137-44. Epub 2014 Jan 8.

Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.

Aim: The PNPLA3 rs738409 C>G polymorphism (encoding for I148M) has recently been identified as a susceptibility factor for steatosis-mediated liver damage. We evaluated the influence of this polymorphism on hepatocarcinogenesis in patients with chronic hepatitis C (CHC) virus infection.

Methods: We genotyped the rs738409 single nucleotide polymorphism in 358 hepatitis C-associated hepatocellular carcinoma (HCC) patients and correlated the age at onset of HCC and the interval between hepatitis C virus (HCV) infection and the development of HCC in patients with each genotype.

Results: The frequencies of CC, CG and GG genotypes were 27.9% (100/358), 49.2% (176/358) and 22.9% (82/358), respectively, and were in Hardy-Weinberg equilibrium. The median age at onset of HCC for the GG genotype was significantly younger compared to for non-GG genotypes (67.81 vs 69.87 years, P < 0.001), and the median interval between HCV infection and the development of HCC was significantly shorter in patients with the GG genotype (39.96 vs 40.85 years, P = 0.008). PNPLA3 GG genotype was also associated with a higher aspartate aminotransferase level (69.5 vs 59.0 IU/L, P = 0.02), lower prothrombin time (73.0% vs 78.0%, P = 0.008) and a higher prevalence of histological steatosis (40.0% vs. 22.2%, P = 0.01) at the time of HCC onset.

Conclusion: The PNPLA3 genotype GG may be associated with accelerated hepatocarcinogenesis in CHC patients through increased steatosis in the liver.
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http://dx.doi.org/10.1111/hepr.12258DOI Listing
October 2014

IL28B minor allele is associated with a younger age of onset of hepatocellular carcinoma in patients with chronic hepatitis C virus infection.

J Gastroenterol 2014 Apr 22;49(4):748-54. Epub 2013 May 22.

Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.

Background: IL28B polymorphisms were shown to be associated with a response to peg-interferon-based treatment in chronic hepatitis C (CHC) and spontaneous clearance. However, little is known about how this polymorphism affects the course of CHC, including the development of hepatocellular carcinoma (HCC). We evaluated the influence of IL28B polymorphisms on hepatocarcinogenesis in CHC patients.

Methods: We genotyped the rs8099917 single-nucleotide polymorphism in 351 hepatitis C-associated HCC patients without history of IFN-based treatment, and correlated the age at onset of HCC in patients with each genotype.

Results: Frequencies of TT, TG, and GG genotypes were 74.3 % (261/351), 24.8 % (87/351), and 0.9 % (3/351), respectively. The mean ages at onset of HCC for TT, TG, and GG genotypes were 69.9, 67.5 and 66.8, respectively. In multivariate analysis, IL28B minor allele (TG and GG genotypes) was an independent risk factor for younger age at onset of HCC (P = 0.02) in males (P < 0.001) with higher body mass index (BMI; P = 0.009). The IL28B minor allele was also associated with a lower probability of having aspartate aminotransferase-to-platelet ratio index (APRI) >1.5 (minor vs. major, 46.7 vs. 58.6 %; P = 0.01), lower AST (69.1 vs. 77.7 IU/L, P = 0.02), lower ALT (67.8 vs. 80.9 IU/L, P = 0.002), higher platelet count (12.8 vs. 11.2 × 10(4)/μL, P = 0.002), and higher prothrombin time (79.3 vs. 75.4 %, P = 0.002).

Conclusions: The IL28B minor allele was associated with lower inflammatory activity and less progressed fibrosis of the liver; however, it constituted a risk factor for younger-age onset of HCC in CHC patients.
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http://dx.doi.org/10.1007/s00535-013-0826-xDOI Listing
April 2014

[Viral hepatitis].

Nihon Rinsho 2012 Nov;70 Suppl 8:583-8

Unit of Disease Control Genome Medicine, Institute of Medical Science, The University of Tokyo.

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November 2012

A genome-wide association study of HCV-induced liver cirrhosis in the Japanese population identifies novel susceptibility loci at the MHC region.

J Hepatol 2013 May 12;58(5):875-82. Epub 2013 Jan 12.

Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Background & Aims: We performed a genome-wide association study (GWAS) of hepatitis C virus (HCV)-induced liver cirrhosis (LC) to identify predictive biomarkers for the risk of LC in patients with chronic hepatitis C (CHC).

Methods: A total of 682 HCV-induced LC cases and 1045 CHC patients of Japanese origin were genotyped by Illumina Human Hap 610-Quad bead Chip.

Results: Eight SNPs which showed possible associations (p<1.0 × 10(-5)) at the GWAS stage were further genotyped using 936 LC cases and 3809 CHC patients. We found that two SNPs within the major histocompatibility complex (MHC) region on chromosome 6p21, rs910049 and rs3135363, were significantly associated with the progression from CHC to LC (pcombined=9.15 × 10(-11) and 1.45 × 10(-10), odds ratio (OR)=1.46 and 1.37, respectively). We also found that HLA-DQA1(*)0601 and HLA-DRB1(*)0405 were associated with the progression from CHC to LC (p=4.53 × 10(-4) and 1.54 × 10(-4) with OR=2.80 and 1.45, respectively). Multiple logistic regression analysis revealed that rs3135363, rs910049, and HLA-DQA1(*)0601 were independently associated with the risk of HCV-induced LC. In addition, individuals with four or more risk alleles for these three loci have a 2.83-fold higher risk for LC than those with no risk allele, indicating the cumulative effects of these variations.

Conclusions: Our findings elucidated the crucial roles of multiple genetic variations within the MHC region as prognostic/predictive biomarkers for CHC patients.
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http://dx.doi.org/10.1016/j.jhep.2012.12.024DOI Listing
May 2013

Soluble MICA and a MICA variation as possible prognostic biomarkers for HBV-induced hepatocellular carcinoma.

PLoS One 2012 14;7(9):e44743. Epub 2012 Sep 14.

Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

MHC class I polypeptide-related chain A (MICA) molecule is induced in response to viral infection and various types of stress. We recently reported that a single nucleotide polymorphism (SNP) rs2596542 located in the MICA promoter region was significantly associated with the risk for hepatitis C virus (HCV)-induced hepatocellular carcinoma (HCC) and also with serum levels of soluble MICA (sMICA). In this study, we focused on the possible involvement of MICA in liver carcinogenesis related to hepatitis B virus (HBV) infection and examined correlation between the MICA polymorphism and the serum sMICA levels in HBV-induced HCC patients. The genetic association analysis revealed a nominal association with an SNP rs2596542; a G allele was considered to increase the risk of HBV-induced HCC (P = 0.029 with odds ratio of 1.19). We also found a significant elevation of sMICA in HBV-induced HCC cases. Moreover, a G allele of SNP rs2596542 was significantly associated with increased sMICA levels (P = 0.009). Interestingly, HCC patients with the high serum level of sMICA (>5 pg/ml) exhibited poorer prognosis than those with the low serum level of sMICA (≤5 pg/ml) (P = 0.008). Thus, our results highlight the importance of MICA genetic variations and the significance of sMICA as a predictive biomarker for HBV-induced HCC.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0044743PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3443094PMC
February 2013

[New antivirals against hepatitis C virus].

Nihon Rinsho 2012 Apr;70(4):664-70

Unit of Disease Control Genome Medicine, The Institute of Medical Science, The University of Tokyo.

Recently, first direct acting antiviral (DAA) against hepatitis C virus (HCV) has just approved in Japan. It is a first generation protease inhibitor, telaprevir. Telaprevir inhibits HCV NS3 & 4A serine protease, and combination with pegylated-interferon and ribavirin has now become a standard of care (SOC) for patients with genotype 1 high viral load hepatitis C. Fortunately, more than 50 new antivirals against HCV are under development including antivirals in preclinical trials. New antivirals are classified into several categories; (1) NS3 & 4A protease inhibitor, (2) NS5B polymerase inhibitor, (3) NS5A inhibitor, (4) host factor targeting antivirals, (5) interferon-related antivirals, and others. Combination of different classes of antivirals without interferon is expected to become a future SOC for hepatitis C.
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April 2012

[New antivirals against hepatitis C virus(protease inhibitors, polymerase inhibitors, and host factor targeting antivirals)].

Nihon Rinsho 2011 May;69 Suppl 4:275-81

Unit of Disease Control Genome Medicine, Institute of Medical Science, University of Tokyo.

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May 2011

Genome-wide association study identifies a susceptibility locus for HCV-induced hepatocellular carcinoma.

Nat Genet 2011 May 17;43(5):455-8. Epub 2011 Apr 17.

Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan.

To identify the genetic susceptibility factor(s) for hepatitis C virus-induced hepatocellular carcinoma (HCV-induced HCC), we conducted a genome-wide association study using 432,703 autosomal SNPs in 721 individuals with HCV-induced HCC (cases) and 2,890 HCV-negative controls of Japanese origin. Eight SNPs that showed possible association (P < 1 × 10(-5)) in the genome-wide association study were further genotyped in 673 cases and 2,596 controls. We found a previously unidentified locus in the 5' flanking region of MICA on 6p21.33 (rs2596542, P(combined) = 4.21 × 10(-13), odds ratio = 1.39) to be strongly associated with HCV-induced HCC. Subsequent analyses using individuals with chronic hepatitis C (CHC) indicated that this SNP is not associated with CHC susceptibility (P = 0.61) but is significantly associated with progression from CHC to HCC (P = 3.13 × 10(-8)). We also found that the risk allele of rs2596542 was associated with lower soluble MICA protein levels in individuals with HCV-induced HCC (P = 1.38 × 10(-13)).
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http://dx.doi.org/10.1038/ng.809DOI Listing
May 2011

Characteristic mutations in hepatitis C virus core gene related to the occurrence of hepatocellular carcinoma.

Cancer Sci 2009 Dec;100(12):2465-8

Unit of Disease Control Genome Medicine, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Chronic hepatitis C virus (HCV) infection often results in hepatocellular carcinoma (HCC). Previous studies have shown that there might be some characteristic mutations in the core region of HCV related to HCC. Thus, we downloaded and analyzed HCV genotype 1b core gene sequences from HCV databases online to identify them. Based on the information of the sequences, 63 from patients with HCC and 188 from non-HCC were enrolled into our analysis. Then, the nucleotides at each position were compared by chi(2)-test between the two groups, and 24 polymorphisms were found to be associated with HCC. Further analysis of these 24 polymorphisms by logistic regression indicated that eight were significantly related to the increased HCC risk: A028C, G209A, C219U/A, U264C, A271C/U, C378U/A, G435A/C, and G481A. Moreover, U303C/A was associated with the decreased HCC risk. These mutations could bring about four amino acid substitutions: K10Q, R70Q, M91L, and G161S. In conclusion, eight characteristic mutations in the HCV-1b core gene related to the occurrence of HCC were identified. The structural and functional alterations of core protein due to these mutations and the relationship with the occurrence of HCC need to be further studied.
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http://dx.doi.org/10.1111/j.1349-7006.2009.01338.xDOI Listing
December 2009

Double-stranded RNA-activated protein kinase inhibits hepatitis C virus replication but may be not essential in interferon treatment.

Liver Int 2010 Feb 16;30(2):311-8. Epub 2009 Oct 16.

Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.

Background: Double-stranded RNA-activated protein kinase (PKR), an interferon (IFN)-stimulated gene, is activated by binding with double-stranded RNA, a putative replicative intermediate of the hepatitis C virus (HCV). Activated PKR phosphorylates the alpha subunit of eukaryotic initiation factor-2 to inhibit the translation of viral protein.

Aims/methods: We established stable PKR knockdown Huh7 cells using RNA interference and investigated the effect of PKR against HCV replication using a subgenomic replicon that expressed luciferase reporter protein and the JFH1 full-length HCV genome.

Results: In stable PKR knockdown cells that harboured a subgenomic replicon, luciferase activity was approximately three times higher than that of control cells, indicating that the subgenomic replicon replicated with a higher efficiency in stable PKR knockdown cells than that in control cells. Furthermore, stable PKR knockdown cells secreted significantly more HCV particles than did control cells after transfection with the full-length HCV genome. The replication of the subgenomic replicon was suppressed by the addition of IFN-alpha in both cells. Although the extent of suppression was significantly lower in stable PKR knockdown than control cells using a low concentration (2.5-5 U/ml) of IFN-alpha, even 10 U/ml IFN-alpha suppressed the replication of subgenomic replicon by >98% in both cells.

Conclusions: Double-stranded RNA-activated protein kinase plays an important role in suppressing HCV replication in an innate state, but may not be essential in IFN therapy.
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http://dx.doi.org/10.1111/j.1478-3231.2009.02144.xDOI Listing
February 2010

Polymorphism of OAS-1 determines liver fibrosis progression in hepatitis C by reduced ability to inhibit viral replication.

Liver Int 2009 Oct 5;29(9):1413-21. Epub 2009 Jun 5.

Department of Gastroenterology, Graduate School of Medicine, University of Tokyo,4-6-1 Shirokanedai, Minato-ku, Tokyo, Japan.

Background: Progression of disease after hepatitis C virus (HCV) infection differs among individuals, indicating a possibility of participation of host genetic factors. 2'-5'-oligoadenylate synthetase 1 (OAS-1), an important component of the innate immune system, has an antiviral function, and may therefore have a certain relationship with progression of disease.

Aim: To evaluate single nucleotide polymorphisms (SNPs) of OAS-1 and its relationship with the disease status of HCV infection.

Methods: Six SNPs of OAS-1 were selected and examined in 409 Japanese patients with chronic HCV infection using the TaqMan PCR genotyping method. The relationship of SNP genotypes and clinical manifestations of patients was analysed. Then, a pair of OAS-1-expression plasmids mimicking the clinical-related SNPs were created and transfected into liver cells carrying the HCV subgenomic replicon or the full-length genome, JFH1, and HCV replication after transfection was compared.

Results: Patients with genotypes A/A, A/G and G/G of an SNP of OAS-1 at the exon 3 of its coding sequence were at gradient increased risks of suffering from higher serum alanine aminotransferase (P<0.001) and aspartate aminotransferase (P=0.001), higher degree of liver fibrosis (P=0.010) and higher presence of liver cirrhosis (P=0.001). By multivariate logistic regression analysis, genotype G/G was an independent factor associated with cirrhosis (P=0.013, odds ratio 3.11, 95% confidence interval 1.27-7.63). In liver cells, OAS-1 with the G allele showed lower ability to inhibit virus replication than OAS-1 with the A allele (P=0.004).

Conclusions: The SNP of OAS-1 at the exon 3 of its coding sequence was associated with progression of disease in Japanese patients with HCV infection.
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http://dx.doi.org/10.1111/j.1478-3231.2009.02061.xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7194156PMC
October 2009

Down-regulation of hedgehog-interacting protein through genetic and epigenetic alterations in human hepatocellular carcinoma.

Clin Cancer Res 2008 Jun;14(12):3768-76

Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.

Purpose: Hedgehog (Hh) signaling is activated in several cancers. However, the mechanisms of Hh signaling activation in hepatocellular carcinoma (HCC) have not been fully elucidated. We analyzed the involvement of Hh-interacting protein (HHIP) gene, a negative regulator of Hh signaling, in HCC.

Experimental Design: Glioma-associated oncogene homologue (Gli) reporter assay, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay, and quantitative real-time reverse transcription-PCR for the target genes of the Hh signals were performed in HHIP stably expressing hepatoma cells. Quantitative real-time PCR for HHIP was performed in hepatoma cells and 36 HCC tissues. The methylation status of hepatoma cells and HCC tissues was also analyzed by sodium bisulfite sequencing, demethylation assay, and quantitative real-time methylation-specific PCR. Loss of heterozygosity (LOH) analysis was also performed in HCC tissues.

Results: HHIP overexpression induced significant reductions of Gli reporter activity, cell viability, and transcription of the target genes of the Hh signals. HHIP was hypermethylated and transcriptionally down-regulated in a subset of hepatoma cells. Treatment with a demethylating agent led to the HHIP DNA demethylation and restoration of HHIP transcription. HHIP transcription was also down-regulated in the majority of HCC tissues, and more than half of HCC tissues exhibited HHIP hypermethylation. The HHIP transcription level in HHIP-methylated HCC tissues was significantly lower than in HHIP-unmethylated HCC tissues. More than 30% of HCC tissues showed LOH at the HHIP locus.

Conclusions: The down-regulation of HHIP transcription is due to DNA hypermethylation and/or LOH, and Hh signal activation through the inactivation of HHIP may be implicated in the pathogenesis of human HCC.
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http://dx.doi.org/10.1158/1078-0432.CCR-07-1181DOI Listing
June 2008

Association of interferon regulatory factor-7 gene polymorphism with liver cirrhosis in chronic hepatitis C patients.

Liver Int 2008 Jul;28(6):798-806

Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.

Background And Aims: Interferon (IFN) regulatory factor 7 (IRF-7) has been shown to play an essential role in the transcriptional activation of virus-inducible cellular genes, especially IFN genes. Polymorphisms of the IRF-7 gene may probably affect both the quality and the quantity of IRF-7. We investigated the role of IRF-7 polymorphisms in Japanese patients with chronic hepatitis C virus (HCV) infection.

Methods: We studied a total of nine polymorphisms of the IRF-7 gene including SNP1047A/G (Lys/Glu) and SNP2157A/G (Gln/Arg) using the Taqman allelic discrimination and sequencing techniques in 406 Japanese patients with chronic HCV infection. We further performed functional analysis of SNP1047 and SNP2157 by transcriptional activation of the IFNA promoter.

Results: We found that SNP1047AG and SNP2157AG genotypes were in complete linkage disequilibrium and were present in a significantly higher proportion in HCV-infected patients with cirrhosis (5.6%) than in those without cirrhosis (1.7%) (P=0.03). Multivariate analysis also revealed that SNP1047 and SNP2157 were independently associated with cirrhosis at an odds ratio of 2.5. Functional analysis revealed that SNP1047G and SNP2157G alleles increased IFNA expression.

Conclusion: SNP1047AG and SNP2157AG genotypes were strongly associated with cirrhosis. SNP1047G and SNP2157G alleles might be used as markers of host factors associated with a higher risk of cirrhosis in Japanese patients with chronic HCV infection.
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http://dx.doi.org/10.1111/j.1478-3231.2008.01725.xDOI Listing
July 2008

Potential contribution of tumor suppressor p53 in the host defense against hepatitis C virus.

Hepatology 2008 Apr;47(4):1136-49

Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.

Unlabelled: Infection by hepatitis C virus (HCV) usually results into chronic hepatitis that can ultimately lead to cirrhosis and hepatocellular carcinoma. Type 1 interferons (IFN-alpha/beta) constitute the primary cellular defense against viral infection including HCV. IFN binding to their receptors activates associated Jak1 and Tyk2 kinases, which ultimately leads to phosphorylation and assembly of a signal transducer and activator of transcription protein (STAT)1-STAT2-interferon regulatory factor (IRF)9 trimetric complex called interferon-stimulated gene factor 3 that translocates into the nucleus and binds to the interferon- stimulated response elements (ISRE), leading to transcriptional induction of several antiviral genes, including double-stranded RNA-activated protein kinase (PKR), 2',5'- oligoadenylate synthetase (OAS), and myxovirus resistance protein A (MxA). Understanding the mechanisms of how the virus evades this cellular innate defense and establishes a chronic infection is the key for the development of better therapeutics against HCV infection. Here, we demonstrate that p53 could have a crucial role in the cellular innate defense against HCV. We observed significantly higher levels of HCV RNA replication and viral protein expression in the Huh7 cells when their p53 expressions were knocked down. Moreover, IFN treatment was less effective in inhibiting the HCV RNA replication in the p53-knocked-down (p53kd) Huh7 cells. In fact, the activation of the ISRE and the induction of ISGs were significantly attenuated in the p53kd Huh7 cells and p53 was found to directly interact with IRF9.

Conclusion: These observations underscore the potential contributions of the tumor suppressor p53 in cellular antiviral immunity against HCV with possible therapeutic implications.
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http://dx.doi.org/10.1002/hep.22176DOI Listing
April 2008