Mikiko Nakamura

Kanazawa University, Kanazawa-shi, Ishikawa-ken, Japan

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Publications (7)43.49 Total impact

  • Article: Gene expression profiling of hepatitis B- and hepatitis C-related hepatocellular carcinoma using graphical Gaussian modeling.
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    ABSTRACT: Background & Aims Gene expression profiling of hepatocellular carcinoma (HCC) and background liver has been studied extensively; however, the relationship between the gene expression profiles of different lesions has not been assessed. METHODS: We examined the expression profiles of 34 HCC specimens (17 hepatitis B virus [HBV]-related and 17 hepatitis C virus [HCV]-related) and 71 non-tumor liver specimens (36 chronic hepatitis B [CH-B] and 35 chronic hepatitis C [CH-C]) using an in-house cDNA microarray consisting of liver-predominant genes. Graphical Gaussian modeling (GGM) was applied to elucidate the interactions of gene clusters among the HCC and non-tumor lesions. RESULTS: In CH-B-related HCC, the expression of vascular endothelial growth factor-family signaling and regulation of T cell differentiation, apoptosis, and survival, as well as development-related genes was up-regulated. In CH-C-related HCC, the expression of ectodermal development and cell proliferation, wnt receptor signaling, cell adhesion, and defense response genes was also up-regulated. Many of the metabolism-related genes were down-regulated in both CH-B- and CH-C-related HCC. GGM analysis of the HCC and non-tumor lesions revealed that DNA damage response genes were associated with AP1 signaling in non-tumor lesions, which mediates the expression of many genes in CH-B-related HCC. In contrast, signal transducer and activator of transcription 1 and phosphatase and tensin homolog were associated with early growth response protein 1 signaling in non-tumor lesions, which potentially promotes angiogenesis, fibrogenesis, and tumorigenesis in CH-C-related HCC. CONCLUSIONS: Gene expression profiling of HCC and non-tumor lesions revealed the predisposing changes of gene expression in HCC. This approach has potential for the early diagnosis and possible prevention of HCC.
    Genomics 02/2013; · 3.02 Impact Factor
  • Article: Acyclic retinoid targets platelet-derived growth factor signaling in the prevention of hepatic fibrosis and hepatocellular carcinoma development.
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    ABSTRACT: Hepatocellular carcinoma (HCC) often develops in association with liver cirrhosis, and its high recurrence rate leads to poor patient prognosis. Although recent evidence suggests that peretinoin, a member of the acyclic retinoid family, may be an effective chemopreventive drug for HCC, published data about its effects on hepatic mesenchymal cells, such as stellate cells and endothelial cells, remain limited. Using a mouse model in which platelet-derived growth factor (PDGF)-C is overexpressed (Pdgf-c Tg), resulting in hepatic fibrosis, steatosis, and eventually, HCC development, we show that peretinoin significantly represses the development of hepatic fibrosis and tumors. Peretinoin inhibited the signaling pathways of fibrogenesis, angiogenesis, and Wnt/β-catenin in Pdgf-c transgenic mice. In vitro, peretinoin repressed the expression of PDGF receptors α/β in primary mouse hepatic stellate cells (HSC), hepatoma cells, fibroblasts, and endothelial cells. Peretinoin also inhibited PDGF-C-activated transformation of HSCs into myofibroblasts. Together, our findings show that PDGF signaling is a target of peretinoin in preventing the development of hepatic fibrosis and HCC.
    Cancer Research 05/2012; 72(17):4459-71. · 7.86 Impact Factor
  • Article: Malnutrition impairs interferon signaling through mTOR and FoxO pathways in patients with chronic hepatitis C.
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    ABSTRACT: Patients with advanced chronic hepatitis C (CH-C) often are malnourished, but the effects of malnutrition on interferon (IFN) signaling and response to treatment have not been determined. We assessed the importance of the nutritional state of the liver on IFN signaling and treatment response. We studied data from 168 patients with CH-C who were treated with the combination of pegylated-IFN and ribavirin. Plasma concentrations of amino acids were measured by mass spectrometry. Liver gene expression profiles were obtained from 91 patients. Huh-7 cells were used to evaluate the IFN signaling pathway, mammalian target of rapamycin complex 1 (mTORC1), and forkhead box O (FoxO). Antiviral signaling induced by branched-chain amino acids (BCAAs) was determined using the in vitro hepatitis C virus replication system. Multivariate logistic regression analysis showed that Fischer's ratio was associated significantly with nonresponders, independent of interleukin-28B polymorphisms or the histologic stage of the liver. Fischer's ratio was correlated inversely with the expression of BCAA transaminase 1, and was affected by hepatic mTORC1 signaling. IFN stimulation was impaired substantially in Huh-7 cells grown in medium that was low in amino acid concentration, through repressed mTORC1 signaling, and increased Socs3 expression, which was regulated by Foxo3a. BCAA could restore impaired IFN signaling and inhibit hepatitis C virus replication under conditions of malnutrition. Malnutrition impaired IFN signaling by inhibiting mTORC1 and activating Socs3 signaling through Foxo3a. Increasing BCAAs to up-regulate IFN signaling might be used as a new therapeutic approach for patients with advanced CH-C.
    Gastroenterology 03/2011; 141(1):128-40, 140.e1-2. · 11.68 Impact Factor
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    Article: Differential interferon signaling in liver lobule and portal area cells under treatment for chronic hepatitis C.
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    ABSTRACT: The mechanisms of treatment resistance to interferon (IFN) and ribavirin (Rib) combination therapy for hepatitis C virus (HCV) infection are not known. This study aims to gain insight into these mechanisms by exploring hepatic gene expression before and during treatment. Liver biopsy was performed in 50 patients before therapy and repeated in 30 of them 1week after initiating combination therapy. The cells in liver lobules (CLL) and the cells in portal areas (CPA) were obtained from 12 patients using laser capture microdissection (LCM). Forty-three patients were infected with genotype 1 HCV, 20 of who were viral responders (genotype 1-Rsp) with treatment outcome of SVR or TR, while 23 were non-responders (genotype 1-nonRsp) with NR. Only seven patients were infected with genotype 2. Before treatment, the expression of IFN and Rib-stimulated genes (IRSGs), apoptosis-associated genes, and immune reaction gene pathways was greater in genotype 1-nonRsp than in Rsp. During treatment, IRSGs were induced in genotype 1-Rsp, but not in nonRsp. IRSG induction was irrelevant in genotype 2-Rsp and was mainly impaired in CLL but not in CPA. Pathway analysis revealed that many immune regulatory pathways were induced in CLL from genotype 1-Rsp, while growth factors related to angiogenesis and fibrogenesis were more induced in CPA from genotype 1-nonRsp. Impaired IRSGs induction in CLL reduces the sensitivity to treatment for genotype 1 HCV infection. CLL and CPA in the liver might be differentially involved in treatment resistance. These findings could be useful for the improvement of therapy for HCV infection.
    Journal of Hepatology 11/2010; 53(5):817-26. · 9.26 Impact Factor
  • Article: Hepatic ISG expression is associated with genetic variation in interleukin 28B and the outcome of IFN therapy for chronic hepatitis C.
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    ABSTRACT: Multiple viral and host factors are related to the treatment response to pegylated-interferon and ribavirin combination therapy; however, the clinical relevance and relationship of these factors have not yet been fully evaluated. We studied 168 patients with chronic hepatitis C who received pegylated-interferon and ribavirin combination therapy. Gene expression profiles in the livers of 91 patients were analyzed using an Affymetrix genechip (Affymetrix, Santa Clara, CA). The expression of interferon-stimulated genes (ISGs) was evaluated in all samples by real-time polymerase chain reaction. Genetic variation in interleukin 28B (IL28B; rs8099917) was determined in 91 patients. Gene expression profiling of the liver differentiated patients into 2 groups: patients with up-regulated ISGs and patients with down-regulated ISGs. A high proportion of patients with no response to treatment was found in the up-regulated ISGs group (P=.002). Multivariate logistic regression analysis showed that ISGs (<3.5) (odds ratio [OR], 16.2; P<.001), fibrosis stage (F1-F2) (OR, 4.18; P=.003), and ISDR mutation (>or=2) (OR, 5.09; P=.003) were strongly associated with the viral response. The IL28B polymorphism of 91 patients showed that 66% were major homozygotes (TT), 30% were heterozygotes (TG), and 4% were minor homozygotes (GG). Interestingly, hepatic ISGs were associated with the IL28B polymorphism (OR, 18.1; P<.001), and its expression was significantly higher in patients with the minor genotype (TG or GG) than in those with the major genotype (TT). The expression of hepatic ISGs is strongly associated with treatment response and genetic variation of IL28B. The differential role of host and viral factors as predicting factors may also be present.
    Gastroenterology 04/2010; 139(2):499-509. · 11.68 Impact Factor
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    Article: Hepatic ISG expression is associated with genetic variation in interleukin 28B and the outcome of IFN therapy for chronic hepatitis C
    [show abstract] [hide abstract]
    ABSTRACT: Background & Aims: Multiple viral and host factors are related to the treatment response to pegylated-interferon and ribavirin combination therapy; however, the clinical relevance and relationship of these factors have not yet been fully evaluated. Methods: We studied 168 patients with chronic hepatitis C who received pegylated-interferon and ribavirin combination therapy. Gene expression profiles in the livers of 91 patients were analyzed using an Affymetrix genechip (Affymetrix, Santa Clara, CA). The expression of interferon-stimulated genes (ISGs) was evaluated in all samples by real-time polymerase chain reaction. Genetic variation in interleukin 28B (IL28B; rs8099917) was determined in 91 patients. Results: Gene expression profiling of the liver differentiated patients into 2 groups: patients with up-regulated ISGs and patients with down-regulated ISGs. A high proportion of patients with no response to treatment was found in the up-regulated ISGs group (P = .002). Multivariate logistic regression analysis showed that ISGs (<3.5) (odds ratio [OR], 16.2; P < .001), fibrosis stage (F1-F2) (OR, 4.18; P = .003), and ISDR mutation (<2) (OR, 5.09; P = .003) were strongly associated with the viral response. The IL28B polymorphism of 91 patients showed that 66% were major homozygotes (TT), 30% were heterozygotes (TG), and 4% were minor homozygotes (GG). Interestingly, hepatic ISGs were associated with the IL28B polymorphism (OR, 18.1; P < .001), and its expression was significantly higher in patients with the minor genotype (TG or GG) than in those with the major genotype (TT). Conclusions: The expression of hepatic ISGs is strongly associated with treatment response and genetic variation of IL28B. The differential role of host and viral factors as predicting factors may also be present. © 2010 AGA Institute.
  • Article: Differential interferon signaling in cells in liver lobules and portal areas under treatment for chronic hepatitis C
    [show abstract] [hide abstract]
    ABSTRACT: Background & Aims: The mechanisms of treatment resistance to interferon (IFN) and ribavirin (Rib) combination therapy for hepatitis C virus (HCV) infection are not known. This study aims to gain insight into these mechanisms by exploring hepatic gene expression before and during treatment. Methods: Liver biopsy was performed in 50 patients before therapy and repeated in 30 of them 1 week after initiating combination therapy. The cells in liver lobules (CLL) and the cells in portal areas (CPA) were obtained from 12 patients using laser capture microdissection (LCM). Results: Forty-three patients were infected with genotype 1 HCV, 20 of who were viral responders (genotype 1-Rsp) with treatment outcome of SVR or TR, while 23 were non-responders (genotype 1-nonRsp) with NR. Only seven patients were infected with genotype 2. Before treatment, the expression of IFN and Rib-stimulated genes (IRSGs), apoptosis-associated genes, and immune reaction gene pathways was greater in genotype 1-nonRsp than in Rsp. During treatment, IRSGs were induced in genotype 1-Rsp, but not in nonRsp. IRSG induction was irrelevant in genotype 2-Rsp and was mainly impaired in CLL but not in CPA. Pathway analysis revealed that many immune regulatory pathways were induced in CLL from genotype 1-Rsp, while growth factors related to angiogenesis and fibrogenesis were more induced in CPA from genotype 1-nonRsp. Conclusions: Impaired IRSGs induction in CLL reduces the sensitivity to treatment for genotype 1 HCV infection. CLL and CPA in the liver might be differentially involved in treatment resistance. These findings could be useful for the improvement of therapy for HCV infection. © 2010 European Association for the Study of the Liver.