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Featured researches published by Takuya Genda.


Lancet Infectious Diseases | 2015

Ledipasvir and sofosbuvir fixed-dose combination with and without ribavirin for 12 weeks in treatment-naive and previously treated Japanese patients with genotype 1 hepatitis C: an open-label, randomised, phase 3 trial

Masashi Mizokami; Osamu Yokosuka; Tetsuo Takehara; Naoya Sakamoto; Masaaki Korenaga; Hitoshi Mochizuki; Kunio Nakane; Hirayuki Enomoto; Fusao Ikeda; Mikio Yanase; Hidenori Toyoda; Takuya Genda; Takeji Umemura; Hiroshi Yatsuhashi; Tatsuya Ide; Nobuo Toda; Kazushige Nirei; Yoshiyuki Ueno; Yoichi Nishigaki; Juan Betular; Bing Gao; Akinobu Ishizaki; Masa Omote; Hongmei Mo; Kim Garrison; Phillip S. Pang; Steven J. Knox; William T. Symonds; John G. McHutchison; Namiki Izumi

BACKGROUNDnCompared with other countries, patients with chronic hepatitis C infection in Japan tend to be older, have more advanced liver disease, and are more likely to have been previously treated for hepatitis C. We aimed to assess the efficacy and safety of an all-oral, fixed-dose combination of the hepatitis C virus NS5A inhibitor ledipasvir and the NS5B nucleotide polymerase inhibitor sofosbuvir with and without ribavirin for 12 weeks in treatment-naive and previously treated Japanese patients with chronic genotype 1 hepatitis C virus infection.nnnMETHODSnIn this randomised, open-label study, we enrolled patients from 19 clinical Japanese centres. Patients were randomly assigned (1:1) to receive either ledipasvir (90 mg) and sofosbuvir (400 mg) or ledipasvir, sofosbuvir, and ribavirin (dosed according to the Japanese Copegus product label-ie, patients ≤60 kg received 600 mg daily, patients >60 kg to ≤80 kg received 800 mg daily, and patients >80 kg received 1000 mg daily) orally once daily for 12 weeks. After completion or early discontinuation of treatment, patients were followed up off-treatment for 24 weeks. Eligible patients were at least 20 years of age with chronic genotype 1 hepatitis C virus infection with serum hepatitis C virus RNA concentrations of at least 5 log10 IU/mL, creatinine clearance of at least 1·0 mL/s, and a platelet count of at least 50u2008×u200810(9) per L. An interactive web response system was used to manage patient randomisation and treatment assignment. Randomisation was stratified by the presence or absence of cirrhosis for treatment-naive patients and stratified by presence or absence of cirrhosis and by previous treatment category (relapser or breakthrough, non-responder, or interferon-intolerant) for previously treated patients. Within each strata, patients were sequentially assigned to either treatment with ledipasvir-sofosbuvir or ledipasvir-sofosbuvir plus ribavirin in a 1:1 ratio with block size of 4. The primary endpoint was sustained virological response 12 weeks after completion of treatment (SVR12) assessed in all patients who were randomly assigned and received at least one dose of study drug; safety outcomes were assessed in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT01975675.nnnFINDINGSnBetween Oct 15, 2013 and Dec 13, 2013, 341 patients were randomly assigned to treatment groups and received at least one dose of study treatment. SVR12 was achieved in all 171 (100%) patients (83 of 83 treatment naive and 88 of 88 treatment experienced) receiving ledipasvir-sofosbuvir (95% CI 98-100) and 167 (98%) of 170 patients (80 of 83 treatment naive and 87 of 87 treatment experienced) receiving ledipasvir-sofosbuvir plus ribavirin (95% CI 95-100). Of the 76 patients with baseline NS5A resistant variants, 75 (99%) achieved SVR12. Two (1·2%) of 170 patients in the ledipasvir-sofosbuvir plus ribavirin group discontinued treatment because of adverse events. The most common adverse events were nasopharyngitis (50 [29·2%] of 171), headache (12 [7·0%] of 171), and malaise (nine [5·3%] of 171) in patients receiving ledipasvir-sofosbuvir; and nasopharyngitis (40 [23·5%] of 170), anaemia (23 [13·5%] of 170), and headache in those receiving ledipasvir-sofosbuvir and ribavirin (15 [8·8%] of 170).nnnINTERPRETATIONnAlthough existing regimens for the treatment of hepatitis C virus are effective for many patients, medical needs remain unmet, particularly in Japan where the population with hepatitis C virus genotype 1 is generally older and treatment-experienced, with advanced liver disease. The efficacy, tolerability, and absence of drug-drug interactions of ledipasvir-sofosbuvir suggest that it could be an important option for treatment of genotype 1 hepatitis C virus in Japanese patients.nnnFUNDINGnGilead Sciences.


Journal of Viral Hepatitis | 2014

Sofosbuvir plus ribavirin in Japanese patients with chronic genotype 2 HCV infection: an open‐label, phase 3 trial

Masao Omata; Shuhei Nishiguchi; Yoshiyuki Ueno; Hitoshi Mochizuki; Namiki Izumi; Fusao Ikeda; Hidenori Toyoda; Osamu Yokosuka; Kazushige Nirei; Takuya Genda; Takeji Umemura; Tetsuo Takehara; Naoya Sakamoto; Yoichi Nishigaki; Kunio Nakane; Nobuo Toda; Tatsuya Ide; Mikio Yanase; Keisuke Hino; Bing Gao; Kimberly L. Garrison; Hadas Dvory-Sobol; Akinobu Ishizaki; Masa Omote; Diana M. Brainard; Steven J. Knox; William T. Symonds; John G. McHutchison; Hiroshi Yatsuhashi; Masashi Mizokami

Genotype 2 hepatitis C virus (HCV) accounts for up to 30% of chronic HCV infections in Japan. The standard of care for patients with genotype 2 HCV – peginterferon and ribavirin for 24 weeks – is poorly tolerated, especially among older patients and those with advanced liver disease. We conducted a phase 3, open‐label study to assess the efficacy and safety of an all‐oral combination of the NS5B polymerase inhibitor sofosbuvir and ribavirin in patients with chronic genotype 2 HCV infection in Japan. We enrolled 90 treatment‐naïve and 63 previously treated patients at 20 sites in Japan. All patients received sofosbuvir 400 mg plus ribavirin (weight‐based dosing) for 12 weeks. The primary endpoint was sustained virologic response at 12 weeks after therapy (SVR12). Of the 153 patients enrolled and treated, 60% had HCV genotype 2a, 11% had cirrhosis, and 22% were over the aged 65 or older. Overall, 148 patients (97%) achieved SVR12. Of the 90 treatment‐naïve patients, 88 (98%) achieved SVR12, and of the 63 previously treated patients, 60 (95%) achieved SVR12. The rate of SVR12 was 94% in patients with cirrhosis and in those aged 65 and older. No patients discontinued study treatment due to adverse events. The most common adverse events were nasopharyngitis, anaemia and headache. Twelve weeks of sofosbuvir and ribavirin resulted in high rates of SVR12 in treatment‐naïve and previously treated patients with chronic genotype 2 HCV infection. The treatment was safe and well tolerated by patients, including the elderly and those with cirrhosis.


Japanese Journal of Cancer Research | 1999

β‐Catenin Accumulation and Mutation of Exon 3 of the β‐Catenin Gene in Hepatocellular Carcinoma

Yutaka Kondo; Yae Kanai; Michiie Sakamoto; Takuya Genda; Masashi Mizokami; Ryuzo Ueda; Setsuo Hirohashi

study was conducted to clarify the contribution of β‐catenin accumulation and mutation of the β‐catenin gene to hepatocarcinogenesis. β‐Catenin accumulation was examined immunohistochemically in 38 paired samples of hepatocellular carcinoma (HCC) and corresponding non‐cancerous liver tissue. Gene mutation was analyzed by polymerase chain reaction‐single strand conformation polymorphism (PCR‐SSCP) and direct sequencing using intronic primers encompassing exon 3. Neither accumulation nor mutation was detected in non‐cancerous liver tissues that showed no remarkable histological features, chronic hepatitis or liver cirrhosis. Accumulation of β‐catenin was seen in the nucleus, cytoplasm or cell membrane in 15 of 38 (39%) HCC samples, and gene mutation was seen in 9 of 38 (24%) HCC samples. Although there was a significant correlation between accumulation and mutation (P<0.01), six HCCs without mutation also showed accumulation. Samples of early HCC showed neither accumulation nor mutation, and accumulation and mutation were each correlated significantly with portal vein tumor involvement (P<0.05). The present results indicate that (1) mutation of exon 3 of the β‐catenin gene can lead to β‐catenin accumulation, although other mechanisms of accumulation may also operate in HCC, and (2) β‐catenin accumulation and mutation of the β‐catenin gene are not early events in hepatocarcinogenesis, and may be associated with the malignant progression of HCC.


Japanese Journal of Cancer Research | 2001

Involvement of c‐Src in Carcinoma Cell Motility and Metastasis

Michiie Sakamoto; Masaaki Takamura; Yoshinori Ino; Ayaka Miura; Takuya Genda; Setsuo Hirohashi

Carcinoma cells exhibit dysfunction/dysregulation of cell adhesion systems that correlates with their abilities to migrate, invade, and metastasize. Here we show that the tyrosine kinase c‐Src is required for motility and metastasis of two carcinoma cell lines. Adherent KYN‐2 cells having a high level of c‐Src kinase activity become scattered, extend lamellipodia, and exhibit high motility. Expression of a dominant‐negative mutant form of c‐Src caused formation of stress fibers and focal adhesions, and markedly reduced motility. HCT15 cells extended lamellipodia and became scattered in response to lysophosphatidic acid stimulation in parallel with transient activation of c‐Src, which was inhibited by expression of a dominant‐negative mutant form of c‐Src or treatment with a specific Src kinase inhibitor. Furthermore, implantation of dominant‐negative c‐Src trans‐fectants into the peritoneal cavity of SCID mice resulted in reduced peritoneal dissemination compared with control transfectants. These findings indicate that c‐Src activation is critically involved in carcinoma cell migration and metastasis.


Gastroenterology | 2017

Genome-Wide Association Study Identifies TLL1 Variant Associated With Development of Hepatocellular Carcinoma After Eradication of Hepatitis C Virus Infection

Kentaro Matsuura; Hiromi Sawai; Kazuho Ikeo; Shintaro Ogawa; Etsuko Iio; Masanori Isogawa; Noritomo Shimada; Atsumasa Komori; Hidenori Toyoda; Takashi Kumada; Tadashi Namisaki; Hitoshi Yoshiji; Naoya Sakamoto; Mina Nakagawa; Yasuhiro Asahina; Masayuki Kurosaki; Namiki Izumi; Nobuyuki Enomoto; Atsunori Kusakabe; Eiji Kajiwara; Yoshito Itoh; Tatsuya Ide; Akihiro Tamori; Misako Matsubara; Norifumi Kawada; Ken Shirabe; Eiichi Tomita; Masao Honda; Shuichi Kaneko; Sohji Nishina

BACKGROUND & AIMSnThere is still a risk for hepatocellular carcinoma (HCC) development after eradication of hepatitis C virus (HCV) infection with antiviral agents. We investigated genetic factors associated with the development of HCC in patients with a sustained virologic response (SVR) to treatment for chronic HCV infection.nnnMETHODSnWe obtained genomic DNA from 457 patients in Japan with a SVR to interferon-based treatment for chronic HCV infection from 2007 through 2015. We conducted a genome-wide association study (GWAS), followed by a replication analysis of 79 candidate single nucleotide polymorphisms (SNPs) in an independent set of 486 patients in Japan. The study end point was HCC diagnosis or confirmation of lack of HCC (at follow-up examinations until December 2014 in the GWAS cohort, and until January 2016 in the replication cohort). We collected clinical and laboratory data from all patients. We analyzed expression levels of candidate gene variants in human hepatic stellate cells, rats with steatohepatitis caused by a choline-deficient L-amino acid-defined diet, and a mouse model of liver injury caused by administration of carbon tetrachloride. We also analyzed expression levels in liver tissues of patients with chronic HCV infection with different stages of fibrosis or tumors vs patients without HCV infection (controls).nnnRESULTSnWe found a strong association between the SNP rs17047200, located within the intron of the tolloid like 1 gene (TLL1) on chromosome 4, and development of HCC; there was a genome-wide level of significance when the results of the GWAS and replication study were combined (odds ratio, 2.37; Pxa0= 2.66xa0× 10-8). Multivariate analysis showed rs17047200 AT/TT to be an independent risk factor for HCC (hazard ratio, 1.78; Pxa0= .008), along with male sex, older age, lower level of albumin, advanced stage of hepatic fibrosis, presence of diabetes, and higher post-treatment level of α-fetoprotein. Combining the rs17047200 genotype with other factors, we developed prediction models for HCC development in patients with mild or advanced hepatic fibrosis. Levels of TLL1 messenger RNA (mRNA) in human hepatic stellate cells increased with activation. Levels of Tll1 mRNA increased in liver tissues of rodents with hepatic fibrogenesis compared with controls. Levels of TLL1 mRNA increased in liver tissues of patients with progression of fibrosis. Gene expression levels of TLL1 short variants, including isoform 2, were higher in patients with rs17047200 AT/TT.nnnCONCLUSIONSnIn a GWAS, we identified the association between the SNP rs17047200, within the intron of TLL1, and development of HCC in patients who achieved an SVR to treatment for chronic HCV infection. We found levels of Tll1/TLL1 mRNA to be increased in rodent models of liver injury and liver tissues of patients with fibrosis, compared with controls. We propose that this SNP might affect splicing of TLL1 mRNA, yielding short variants with high catalytic activity that accelerates hepatic fibrogenesis and carcinogenesis. Further studies are needed to determine how rs17047200 affects TLL1 mRNA levels, splicing, and translation, as well as the prevalence of this variant among other patients with HCC. Tests for the TLL1 SNP might be used to identify patients at risk for HCC after an SVR to treatment of HCV infection.


Journal of Gastroenterology | 2014

Waiting list mortality of patients with primary biliary cirrhosis in the Japanese transplant allocation system.

Takuya Genda; Takafumi Ichida; Shotaro Sakisaka; Michio Sata; Eiji Tanaka; Ayano Inui; Hiroto Egawa; Umeshita K; Hiroyuki Furukawa; Seiji Kawasaki; Yukihiro Inomata

BackgroundThe present study aimed to evaluate etiology-based differences in the risk of waiting list mortality, and to compare the current Japanese transplant allocation system with the Child–Turcotte–Pugh (CTP) and the Model for End-Stage Liver Disease (MELD) scoring systems with regard to the risk of waiting list mortality in patients with primary biliary cirrhosis (PBC).MethodsUsing data derived from all adult candidates for deceased donor liver transplantation in Japan from 1997 to 2011, we assessed factors associated with waiting list mortality by the Cox proportional hazards model. The waiting list mortality risk of PBC patients was further estimated with adjustment for each scoring system.ResultsOf the 1056 patients meeting the inclusion criteria, 743 were not on the list at the end of study period; waiting list mortality was 58.1xa0% in this group. In multivariate analysis, increasing age and PBC were significantly associated with an increased risk of waiting list mortality. In comparison with patients with hepatitis C virus (HCV) infection, PBC patients were at 79xa0% increased risk and had a shorter median survival time by approximately 8xa0months. The relative hazard of PBC patients was statistically significant with adjustment for CTP score and medical point score, which was the priority for ranking candidates in the Japanese allocation system. However, it lost significance with adjustment for MELD score. Stratification by MELD score indicated a comparable waiting list survival time between patients with PBC and HCV.ConclusionsPBC patients are at high risk of waiting list mortality in the current allocation system. MELD-based allocation could reduce this risk.


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.


Medical Molecular Morphology | 2013

Clinical significance of cell cycle inhibitors in hepatocellular carcinoma

Yasunobu Matsuda; Toshifumi Wakai; Masayuki Kubota; Masaaki Takamura; Satoshi Yamagiwa; Yutaka Aoyagi; Mami Osawa; Shun Fujimaki; Ayumi Sanpei; Takuya Genda; Takafumi Ichida

It is well accepted that cell cycle regulators are strongly implicated in the progression of cancer development. p16 and p27 are potent cyclin-dependent kinase (CDK) inhibitors involved in G1 phase progression, and are regarded as adverse prognostic biomarkers for various types of cancers. It has been reported that the main mechanism for p16 inactivation is aberrant DNA methylation, while p27 is exclusively inactivated by proteasome-mediated protein degradation. We have found that p27 is decreased in around half of hepatocellular carcinomas (HCCs), and in some cases p27 is inactivated by inappropriate interaction with cyclin D1/CDK4 complexes. In such cases, p16 is concomitantly inactivated through DNA methylation. Taking into consideration the complex interaction between p16 and p27, a comprehensive analysis including p16 and p27 would be useful for predicting the prognosis of HCC patients.


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.

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