Fumitake Amemiya

Outcome of hypovascular hepatic nodules revealing no gadoxetic acid uptake in patients with chronic liver disease.

To elucidate the natural history of hypovascular nodules that appear hypointense on hepatocyte‐phase gadoxetic acid‐enhanced MR images by focusing on hypervascularization over time.

Double-dose gadoxetic Acid-enhanced magnetic resonance imaging in patients with chronic liver disease.

Objectives:To determine the effect of double-dose gadoxetic-acid (Gd-EOB-DTPA) on lesion-liver contrast ratio in arterial- and hepatocyte-phase images and arterial-phase image quality in patients with chronic liver disease. Materials and Methods:The ethics committee at our institute approved this study. This study included 28 patients (13 with Child-Pugh class A and 15 with class B) with 54 hepatocellular carcinomas. All patients received the standard Gd-EOB-DTPA dose (0.025 mmol/kg bodyweight) and double dose (0.050 mmol/kg bodyweight). The lesion-liver contrast ratio was evaluated in arterial- and hepatocyte-phase images. The artifacts in arterial-phase images were evaluated with a 4-point scale. Wilcoxon signed-rank test were used for comparisons. Results:The hepatocyte-phase lesion-liver contrast ratio after the double dose was significantly higher than that after the standard dose in patients with Child-Pugh class B disease(standard dose vs. double dose; 0.20 ± 0.16 vs. 0.25 ± 0.17; P < 0.0001); however, the ratio after both the standard and double doses was equivalent in patients with Child-Pugh class A disease (0.35 ± 0.18 vs. 0.35 ± 0.14; P = 0.3038). The double dose significantly increased the arterial-phase lesion-liver contrast ratio (0.34 ± 0.19 vs. 0.58 ± 0.33; P < 0.0001). The artifacts in the arterial-phase images were more prominent after the standard dose (2.7 vs. 2.4 for reader 1, 2.8 vs. 2.4 for reader 2; P = 0.0195 and 0.0010). Conclusions:Administration of double dose of Gd-EOB-DTPA provided better arterial enhancement of hepatocellular carcinomas in patients with chronic liver disease, and also improved the lesion-liver contrast in hepatocyte-phase images in patients with Child-Pugh class B disease.

Deep sequencing analysis of variants resistant to the non-structural 5A inhibitor daclatasvir in patients with genotype 1b hepatitis C virus infection

Daclatasvir, a non‐structural (NS)5A replication complex inhibitor, is a potent and promising direct antiviral agent (DAA) for hepatitis C virus (HCV), being most effective in genotype 1b infection. Although it is known that genotype 1b viruses with Y93H and/or L31M/V/F mutations have strong resistance to daclatasvir, it is not known whether there are some clinical background conditions that favor the occurrence of HCV carrying those NS5A mutations.

Cross-validation of MR elastography and ultrasound transient elastography in liver stiffness measurement: discrepancy in the results of cirrhotic liver†

To evaluate individual differences in liver stiffness measurement using both MR elastography (MRE) and ultrasound transient elastography (UTE) in patients with chronic liver disease.

Hepatocellular carcinoma risk assessment using gadoxetic acid-enhanced hepatocyte phase magnetic resonance imaging.

To investigate whether the patients with hypovascular liver nodules determined on the arterial phase and hypointensity on the hepatocyte phase gadoxetic acid‐enhanced magnetic resonance imaging (hypovascular hypointense nodules) are at increased risk of hepatocarcinogenesis, we assessed subsequent typical hepatocellular carcinoma (HCC) development at any sites of the liver with and without such nodules.

IL-28B (IFN-λ3) and IFN-α synergistically inhibit HCV replication

Genetic variation in the IL‐28B (interleukin‐28B; interferon lambda 3) region has been associated with sustained virological response (SVR) rates in patients with chronic hepatitis C treated with peginterferon‐α and ribavirin. However, the mechanisms by which polymorphisms in the IL‐28B gene region affect host antiviral responses are not well understood. Using the HCV 1b and 2a replicon system, we compared the effects of IFN‐λs and IFN‐α on HCV RNA replication. The anti‐HCV effect of IFN‐λ3 and IFN‐α in combination was also assessed. Changes in gene expression induced by IFN‐λ3 and IFN‐α were compared using cDNA microarray analysis. IFN‐λs at concentrations of 1 ng/mL or more exhibited concentration‐ and time‐dependent HCV inhibition. In combination, IFN‐λ3 and IFN‐α had a synergistic anti‐HCV effect; however, no synergistic enhancement was observed for interferon‐stimulated response element (ISRE) activity or upregulation of interferon‐stimulated genes (ISGs). With respect to the time course of ISG upregulation, the peak of IFN‐λ3‐induced gene expression occurred later and lasted longer than that induced by IFN‐α. In addition, although the genes upregulated by IFN‐α and IFN‐λ3 were similar to microarray analysis, interferon‐stimulated gene expression appeared early and was prolonged by combined administration of these two IFNs. In conclusion, IFN‐α and IFN‐λ3 in combination showed synergistic anti‐HCV activity in vitro. Differences in time‐dependent upregulation of these genes might contribute to the synergistic antiviral activity.

Comprehensive analysis for viral elements and interleukin‐28B polymorphisms in response to pegylated interferon plus ribavirin therapy in hepatitis C virus 1B infection

To comprehensively characterize the contribution of virological factors as well as interleukin‐28B (IL28B) single‐nucleotide polymorphisms (SNPs) in determining treatment responses in pegylated‐interferon plus ribavirin (Peg‐IFN/RBV) therapy for chronic hepatitis C virus (HCV)‐1b infection, we undertook a retrospective cohort analysis for the pretreatment dominant complete HCV open reading frame (ORF) amino‐acid (aa) sequence study in 103 consecutive HCV‐1b Japanese patients. The dominant HCV sequences classified by the response were subjected to systematic sliding‐window comparison analysis to characterize response‐specific viral sequences, along with IL28B SNP analyses (rs8099917). In each comparison of the patients between with and without rapid viral response (RVR), nonearly viral response (nEVR), sustained virological response (SVR), or relapse, the following regions were extracted as most significantly associated with the different responses respectively: nonstructural protein 5A (NS5A) aa.2224‐2248 (P = 1.2E‐07); core aa.70 (P = 4E‐04); NS5A aa.2340‐2382 (P = 7.0E‐08); and NS5A aa.2360‐2377 (P = 1.1E‐05). Those NS5A regions nearly coincided with the interferon (IFN) sensitivity‐determining region (NS5A aa.2209‐2248) and the IFN/RBV resistance‐determining region (NS5A aa.2339‐2379). In a multivariate analysis, the IL28B SNP (odds ratio [OR] = 16.8; P = 0.009) and NS5A aa.2340‐2382 (OR = 13.8; P = 0.0003) were extracted as the two most‐significant independent variables contributing to the final outcome. Conclusion: In Peg‐IFN/RBV therapy, polymorphisms in IL28B, NS5A aa.2224‐2248, core aa.70, and, most important, NS5A aa.2340‐2382 have a tremendous influence on treatment response in association with viral kinetics, resulting in significantly different outcomes in chronic HCV‐1b infection. (HEPATOLOGY 2012;56:1611–1621)

Deep Sequencing and Phylogenetic Analysis of Variants Resistant to Interferon-Based Protease Inhibitor Therapy in Chronic Hepatitis Induced by Genotype 1b Hepatitis C Virus

ABSTRACT Because of recent advances in deep sequencing technology, detailed analysis of hepatitis C virus (HCV) quasispecies and their dynamic changes in response to direct antiviral agents (DAAs) became possible, although the role of quasispecies is not fully understood. In this study, to clarify the evolution of viral quasispecies and the origin of drug-resistant mutations induced by interferon (IFN)-based protease inhibitor therapy, the nonstructural-3 (NS3) region of genotype 1b HCV in 34 chronic hepatitis patients treated with telaprevir (TVR)/pegylated interferon (PEG-IFN)/ribavirin (RBV) was subjected to a deep sequencing study coupled with phylogenetic analysis. Twenty-six patients (76.5%) achieved a sustained viral response (SVR), while 8 patients did not (non-SVR; 23.5%). When the complexity of the quasispecies was expressed as the mutation frequency or Shannon entropy value, a significant decrease in the IFNL3 (rs8099917) TT group and a marginal decrease in the SVR group were found soon (12 h) after the introduction of treatment, whereas there was no decrease in the non-SVR group and no significant decrease in mutation frequency in the IFNL3 TG/GG group. In the analysis of viral quasispecies composition in non-SVR patients, major populations greatly changed, accompanied by the appearance of resistance, and the compositions were unlikely to return to the pretreatment composition even after the end of therapy. Clinically TVR-resistant variants were observed in 5 non-SVR patients (5/8, 62.5%), all of which were suspected to have acquired resistance by mutations through phylogenetic analysis. In conclusion, results of the study have important implications for treatment response and outcome in interferon-based protease inhibitor therapy. IMPORTANCE In the host, hepatitis C virus (HCV) consists of a variety of populations (quasispecies), and it is supposed that dynamic changes in quasispecies are closely related to pathogenesis, although this is poorly understood. In this study, recently developed deep sequencing technology was introduced, and changes in quasispecies associated with telaprevir (TVR)/pegylated interferon (PEG-IFN)/ribavirin (RBV) triple therapy and their clinical significance were investigated extensively by phylogenetic tree analysis. Through this study, the associations among treatment response, changes in viral quasispecies complexity in the early stage of treatment, changes in the quasispecies composition, and origin of TVR-resistant variant HCV were elucidated.

Liver stiffness measurement for risk assessment of hepatocellular carcinoma

Liver fibrosis is a risk factor for hepatocellular carcinoma (HCC), but at what fibrotic stage the risk for HCC is increased has been poorly investigated quantitatively. This study aimed to determine the appropriate cut‐off value of liver stiffness for HCC concurrence by FibroScan, and its clinical significance in hepatitis B virus (HBV), hepatitis C virus (HCV) and non‐B, non‐C (NBNC) liver disease.

Analysis of the complete open reading frame of genotype 2b hepatitis C virus in association with the response to peginterferon and ribavirin therapy.

Background and Aims Patients infected with genotype 2b hepatitis C virus (HCV) generally can achieve favorable responses to pegylated-interferon plus ribavirin therapy (PEG-IFN/RBV). However, a proportion of patients show poorer responses and the correlation between viral sequence variation and treatment outcome remains unclear. Methods The pretreatment complete open reading frame (ORF) sequences of genotype 2b HCV determined by direct sequencing were investigated for correlation with the final outcome in a total of 60 patients. Results In this study group, 87.5% (14/16) of non-sustained virological response (non-SVR) patients (n = 16) were relapsers. Compared to sustained virological response (SVR) patients (n = 44), non-SVR patients were older and could not achieve prompt viral clearance after the therapy induction. Comparing each viral protein between the two groups, viral sequences were more diverse in SVR patients and that diversity was found primarily in the E1, p7, and NS5A proteins. In searching for specific viral regions associated with the final outcome, several regions in E2, p7, NS2, NS5A, and NS5B were extracted. Among these regions, part of the interferon sensitivity determining region (ISDR) was included. In these regions, amino acid substitutions were associated with the final outcome in an incremental manner, depending upon the number of substitutions. Conclusions Viral sequences are more diverse in SVR patients than non-SVR patients receiving PEG-IFN/RBV therapy for genotype-2b HCV infection. Through systematic comparison of viral sequences, several specific regions, including part of the ISDR, were extracted as having significant correlation with the final outcome.