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Featured researches published by Yutaka Narita.


International Journal of Molecular Sciences | 2014

Expression of Aldo-Keto Reductase Family 1 Member B10 in the Early Stages of Human Hepatocarcinogenesis

Hi ronori Tsuzura; Takuya Genda; Shunsuke Sato; Ayato Murata; Yoshio Kanemitsu; Yutaka Narita; Sachiko Ishikawa; Tetsu Kikuchi; Masashi Mori; Katsuharu Hirano; Katsuyori Iijima; Ryo Wada; Takafumi Ichida

Aldo-keto reductase family 1, member B10 (AKR1B10), a cancer-related oxidoreductase, is expressed in well-differentiated hepatocellular carcinomas (HCCs). However, AKR1B10 levels are minimal in normal liver tissues (NLs), similar to the 70-kilodalton heat shock protein (HSP70) and glypican-3. Moreover, the role of AKR1B10 in chronic hepatitis or cirrhosis, which are considered preneoplastic conditions for HCC, has not been fully elucidated. The aim of this study was to evaluate the expression of AKR1B10, HSP70, and glypican-3 in 61 HCC tissue samples compared to corresponding non-tumorous liver tissues (NTs), comprising 42 chronic hepatitis and 19 cirrhosis cases to clarify the significance of molecular changes at the preneoplastic stages of HCC. Immunohistochemical analysis demonstrated that the median expression levels of AKR1B10 were higher in HCCs than in NTs (p < 0.001) and higher in NTs than NLs (p < 0.001) with 54.8%, 2.1%, and 0.3% expression in HCCs, NTs, and NLs, respectively. HSP70 and glypican-3 were expressed in HCCs, but minimally in NTs and NLs with no significant difference between expression in NTs and NLs. Furthermore, a multivariate analysis identified an association between hepatic steatosis and AKR1B10 expression in NTs (p = 0.020). Of the three protein expressed in well-differentiated HCCs, only AKR1B10 was upregulated in preneoplastic conditions, and a steatosis-related factor might influence its expression.


Liver International | 2012

Up-regulated aldo-keto reductase family 1 member B10 in chronic hepatitis C: association with serum alpha-fetoprotein and hepatocellular carcinoma.

Shunsuke Sato; Takuya Genda; Katsuharu Hirano; Hironori Tsuzura; Yutaka Narita; Yoshio Kanemitsu; Tetsu Kikuchi; Katsuyori Iijima; Ryo Wada; Takafumi Ichida

Elevated serum alpha‐fetoprotein (AFP) is not only a diagnostic marker for hepatocellular carcinoma (HCC), but is also a risk factor for HCC in chronic hepatitis C patients who do not have HCC.


Journal of Gastroenterology and Hepatology | 2014

Prediction of liver stiffness hepatocellular carcinoma in chronic hepatitis C patients on interferon-based anti-viral therapy.

Yutaka Narita; Takuya Genda; Hironori Tsuzura; Shunsuke Sato; Yoshio Kanemitsu; Sachiko Ishikawa; Tetsu Kikuchi; Katsuharu Hirano; Katsuyori Iijima; Ryo Wada; Takafumi Ichida

The purpose of this study was to evaluate the usefulness of liver stiffness measurement (LSM) for assessing the risk of hepatocellular carcinoma (HCC) in chronic hepatitis C (CHC) patients receiving interferon (IFN) therapy.


Journal of Gastroenterology and Hepatology | 2016

Impact of aldo-keto reductase family 1 member B10 on the risk of hepatitis C virus-related hepatocellular carcinoma.

Shunsuke Sato; Takuya Genda; Takafumi Ichida; Ayato Murata; Hironori Tsuzura; Yutaka Narita; Yoshio Kanemitsu; Sachiko Ishikawa; Tetsu Kikuchi; Masashi Mori; Katsuharu Hirano; Katsuyori Iijima; Ryo Wada; Akihito Nagahara; Sumio Watanabe

Aldo‐keto reductase family 1 member B10 (AKR1B10), a cancer‐related oxidoreductase, was recently reported to be upregulated in some chronic liver diseases. However, its relevance in hepatocellular carcinoma (HCC) development is not fully assessed, especially in patients with chronic hepatitis C virus (HCV) infection.


International Journal of Molecular Sciences | 2016

Prediction of Hepatocellular Carcinoma Development after Hepatitis C Virus Eradication Using Serum Wisteria floribunda Agglutinin-Positive Mac-2-Binding Protein

Shunsuke Sato; Takuya Genda; Takafumi Ichida; Nozomi Amano; Sho Sato; Ayato Murata; Hironori Tsuzura; Yutaka Narita; Yoshio Kanemitsu; Katsuharu Hirano; Yuji Shimada; Katsuyori Iijima; Ryo Wada; Akihito Nagahara; Sumio Watanabe

We aimed to clarify the association between a novel serum fibrosis marker, Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+-M2BP), and hepatocellular carcinoma (HCC) development in 355 patients with chronic hepatitis C who achieved sustained virologic response (SVR) through interferon-based antiviral therapy. Pretreatment serum WFA+-M2BP levels were quantified and the hazard ratios (HRs) for HCC development were retrospectively analyzed by Cox proportional hazard analysis. During the median follow-up time of 2.9 years, 12 patients developed HCC. Multivariate analysis demonstrated that high serum WFA+-M2BP (≥2.80 cut off index (COI), HR = 15.20, p = 0.013) and high fibrosis-4 (FIB-4) index (≥3.7, HR = 5.62, p = 0.034) were independent risk factors for HCC development. The three- and five-year cumulative incidence of HCC in patients with low WFA+-M2BP were 0.4% and 0.4%, respectively, whereas those of patients with high WFA+-M2BP were 7.7% and 17.6%, respectively (p < 0.001). In addition, combination of serum WFA+-M2BP and FIB-4 indices successfully stratified the risk of HCC: the five-year cumulative incidences of HCC were 26.9%, 6.8%, and 0.0% in patients with both, either, and none of these risk factors, respectively (p < 0.001). In conclusion, pretreatment serum WFA+-M2BP level is a useful predictor for HCC development after achieving SVR.


Hepatology Research | 2017

Aldo-keto reductase family 1 member B10 is associated with hepatitis B virus-related hepatocellular carcinoma risk

Masashi Mori; Takuya Genda; Takafumi Ichida; Ayato Murata; Masato Kamei; Hironori Tsuzura; Shunsuke Sato; Yutaka Narita; Yoshio Kanemitsu; Sachiko Ishikawa; Tetsu Kikuchi; Yuji Shimada; Katsuharu Hirano; Katsuyori Iijima; Ken Sugimoto; Ryo Wada; Akihito Nagahara; Sumio Watanabe

Recent reports have indicated that aldo‐keto reductase family 1 member B10 (AKR1B10), a cancer‐related oxidoreductase, was upregulated in some chronic liver diseases. However, few studies have reported AKR1B10 expression in chronic hepatitis B virus (HBV)‐infected patients. The aim of the present study was to analyze AKR1B10 expression and its relevance on hepatocellular carcinoma (HCC) development in patients with chronic HBV infection.


World Journal of Gastroenterology | 2016

Pretreatment AKR1B10 expression predicts the risk of hepatocellular carcinoma development after hepatitis C virus eradication

Ayato Murata; Takuya Genda; Takafumi Ichida; Nozomi Amano; Sho Sato; Hironori Tsuzura; Shunsuke Sato; Yutaka Narita; Yoshio Kanemitsu; Yuji Shimada; Katsuharu Hirano; Katsuyori Iijima; Ryo Wada; Akihito Nagahara; Sumio Watanabe

AIM To clarify the association between aldo-keto reductase family 1 member B10 (AKR1B10) expression and hepatocarcinogenesis after hepatitis C virus eradication. METHODS In this study, we enrolled 303 chronic hepatitis C patients who had achieved sustained virological response (SVR) through interferon-based antiviral therapy. Pretreatment AKR1B10 expression in the liver was immunohistochemically assessed and quantified as a percentage of positive staining area by using image-analysis software. A multivariate Cox analysis was used to estimate the hazard ratios (HRs) of AKR1B10 expression for hepatocellular carcinoma (HCC) development after achieving SVR. The cumulative incidences of HCC development were evaluated using Kaplan-Meier analysis and the log-rank test. RESULTS Of the 303 chronic hepatitis C patients, 153 (50.5%) showed scarce hepatic AKR1B10 expression, quantified as 0%, which was similar to the expression in control normal liver tissues. However, the remaining 150 patients (49.5%) exhibited various degrees of AKR1B10 expression in the liver, with a maximal AKR1B10 expression of 73%. During the median follow-up time of 3.6 years (range 1.0-10.0 years), 8/303 patients developed HCC. Multivariate analysis revealed that only high AKR1B10 expression (≥ 8%) was an independent risk factor for HCC development (HR = 15.4, 95%CI: 1.8-132.5, P = 0.012). The 5-year cumulative incidences of HCC development were 13.7% and 0.5% in patients with high and low AKR1B10 expression, respectively (P < 0.001). During the follow-up period after viral eradication, patients expressing high levels of AKR1B10 expressed markedly higher levels of alanine aminotransferase and α-fetoprotein than did patients exhibiting low AKR1B10 expression. CONCLUSION Chronic hepatitis C patients expressing high levels of hepatic AKR1B10 had an increased risk of HCC development even after SVR.


Hepatology International | 2013

Differences in the factors associated with serum viral load between genotypes 1 and 2 in patients with chronic hepatitis C

Shunsuke Sato; Takuya Genda; Katsuharu Hirano; Hironori Tsuzura; Yoshio Kanemitsu; Yutaka Narita; Tetsu Kikuchi; Katsuyori Ijima; Takafumi Ichida

PurposeThe serum hepatitis C virus (HCV) load is persistently stable in patients with untreated chronic hepatitis C, but its differences between individuals vary widely (above 4 logU/mL). Because serum viral load is an important factor for predicting clinical outcome of interferon-based antiviral therapy, this study was performed to clarify the factors associated with serum viral load in chronic hepatitis C patients.MethodsWe retrospectively analyzed data from 669 chronic hepatitis C patients with HCV genotype 1 or 2 infection. Stepwise regression analysis was used to estimate the relationship between demographic, viral, or biochemical variables and serum viral load.ResultsIn univariate analysis, serum lipid profiles, such as total cholesterol, low-density lipoprotein (LDL) and triglyceride levels, and hemoglobin A1c (HbA1c) were correlated with the serum HCV viral load. In multivariate analysis, HCV genotype 1 infection and higher total cholesterol levels were associated with higher viral load. After stratification by HCV genotype, the serum viral load was associated with triglyceride and HbA1c in genotype 1 and with platelet counts and LDL in genotype 2. Histological data (413 patients) showed correlation between severe liver fibrosis and decreased serum viral load in patients with HCV genotype 2 but not genotype 1 infection.ConclusionsThese results suggest that viral kinetics is affected by different host factors for genotypes 1 and 2.


Internal Medicine | 2013

Association of Visceral Obesity with High Viral Load and Histological Findings in Elderly Patients with Genotype 1 Chronic Hepatitis C

Hironori Tsuzura; Takuya Genda; Shunsuke Sato; Katsuharu Hirano; Yoshio Kanemitsu; Yutaka Narita; Tetsu Kikuchi; Katsuyori Iijima; Ryo Wada; Takafumi Ichida


Journal of Gastroenterology | 2006

Model for end-stage liver disease (MELD) score and cost-effectiveness on living donor liver transplantation.

Takafumi Ichida; Yutaka Narita; Romi Murakami

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