IL-28B variant as a predictor in patients with advanced hepatocellular carcinoma treated with hepatic arterial infusion chemotherapy.

BACKGROUND AND AIM: Single-nucleotide polymorphisms (SNPs) of the interleukin-28B (IL-28B) gene are associated with the effectiveness of interferon therapy for chronic hepatitis C infection. Whether the IL-28B genotype affects the course of treatment and the outcomes of patients with advanced hepatocellular carcinoma (HCC) is unknown. METHODS: We detected the IL-28B SNP (rs8099917) using TaqMan PreDesigned SNP Genotyping Assays to assess the effects of the IL-28B genotype on treatment efficacy and prognosis of patients with advanced HCC treated with hepatic arterial infusion chemotherapy (HAIC) between September 2003 and January 2015. RESULTS: The study included 154 patients who received HAIC to treat advanced HCC, among which 27 (17.5%) had the minor genotype, IL-28B rs8099917 TG or GG, and the others had the major genotype, IL-28B rs8099917 TT. The objective response rates of patients with the minor or major genotype were 51.9% and 29.1% (P = 0.022), respectively. Multivariate analysis revealed that the minor genotype remained associated with the response to HAIC (odds ratio, 2.620; P = 0.026). The median overall survival of patients with major or minor genotypes was 14.1 and 16.9 months, respectively, and the overall survival of patients with the major genotype was significantly shorter than that of patients with the minor genotype (P = 0.027). Multivariate analysis revealed that the major genotype was an independent, unfavorable prognostic factor (hazard ratio, 1.720; P = 0.024). Consistent results were obtained in selected populations after propensity score matching analysis. CONCLUSIONS: The IL-28B SNP (rs8099917) will serve as a useful predictor of the outcomes of patients with advanced HCC treated with HAIC.

Hepatic interferon-stimulated genes are differentially regulated in the liver of chronic hepatitis C patients with different interleukin-28B genotypes.

UNLABELLED: Pretreatment up-regulation of hepatic interferon (IFN)-stimulated genes (ISGs) has a stronger association with the treatment-resistant interleukin (IL)28B minor genotype (MI; TG/GG at rs8099917) than with the treatment-sensitive IL28B major genotype (MA; TT at rs8099917). We compared the expression of ISGs in the liver and blood of 146 patients with chronic hepatitis C who received pegylated IFN and ribavirin combination therapy. Gene expression profiles in the liver and blood of 85 patients were analyzed using an Affymetrix GeneChip (Affymetrix, Santa Clara, CA). ISG expression was correlated between the liver and blood of the MA patients, whereas no correlation was observed in the MI patients. This loss of correlation was the result of the impaired infiltration of immune cells into the liver lobules of MI patients, as demonstrated by regional gene expression analysis in liver lobules and portal areas using laser capture microdissection and immunohistochemical staining. Despite having lower levels of immune cells, hepatic ISGs were up-regulated in the liver of MI patients and they were found to be regulated by multiple factors, namely, IL28A/B, IFN-λ4, and wingless-related MMTV integration site 5A (WNT5A). Interestingly, WNT5A induced the expression of ISGs, but also increased hepatitis C virus replication by inducing the expression of the stress granule protein, GTPase-activating protein (SH3 domain)-binding protein 1 (G3BP1), in the Huh-7 cell line. In the liver, the expression of WNT5A and its receptor, frizzled family receptor 5, was significantly correlated with G3BP1. CONCLUSIONS: Immune cells were lost and induced the expression of other inflammatory mediators, such as WNT5A, in the liver of IL28B minor genotype patients. This might be related to the high level of hepatic ISG expression in these patients and the treatment-resistant phenotype of the IL28B minor genotype.

Sodium dodecylsulfate bilayer formation under a cationic surfactant Langmuir monolayer at the air-water interface.

An aqueous solution of sodium dodecylsulfate (SDS) was injected into a Langmuir monolayer of dioctadecyldimethylammonium chloride (DODAC) at the air-water interface. Infrared external spectra, atomic force microscopy (AFM), and quartz crystal microbalance (QCM) measurements revealed that the resulting surface monolayer was a multilayer structure consisting of a DODAC monolayer as the upper layer and an SDS bilayer as the underlayer. Furthermore, the SDS alkyl chain was in the all-trans conformation, and the molecular packing of the DODAC alkyl chains was hexagonal with the trans-zigzag plane of the methylene chain oriented randomly around the chain axis. We also discuss the structure of the multilayer obtained by injecting SDS into a mixed Langmuir monolayer of DODAC + SDS.

Malnutrition impairs interferon signaling through mTOR and FoxO pathways in patients with chronic hepatitis C.

BACKGROUND & AIMS: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Hepatic ISG expression is associated with genetic variation in interleukin 28B and the outcome of IFN therapy for chronic hepatitis C.

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 (>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). 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.

Oligomeric interaction of hepatitis C virus NS5B is critical for catalytic activity of RNA-dependent RNA polymerase.

HCV NS5B is an RNA-dependent RNA polymerase (RdRP), a central catalytic enzyme for HCV replication, which has the "palm and fingers" substructure. We recently identified five novel residues critical for RdRP activity (Qin, W., Yamashita, T., Shirota, Y., Lin, Y., Wei, W., and Murakami, S. (2001) Hepatology 33, 728-737). Among them, GLU-18 and His-502, far from the catalytic center, may be involved in conformational change(s) for RdRP activity as addressed in some palm and fingers enzymes. We examined the possibility that NS5B is oligomerized, and we could detect the interaction between two different tagged NS5B proteins in vitro and transiently expressed in mammalian cells. By scanning 27 clustered and then point alanine substitutions in vivo and in vitro, Glu-18 and His-502 were found to be critical for the homomeric interaction in vivo and in vitro, strongly suggesting a close relationship between the oligomerization and RdRP activity of NS5B. All mutants with substitutions at these two residues failed to bind wild type NS5B, however E18H interacted with H502E in vitro and in vivo. Interestingly, the NS5B protein with E18H or H502E did not exhibit RdRP activity, but a mixture of the two mutant proteins did. These results clearly indicate that two residues of HCV NS5B are critical for the oligomerization that is prerequisite to RdRP activity.