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IFN-lambda (IFNλ) is a member of the type III IFN family and is reported to possess anti-pathogen, anti-cancer, and immunomodulatory properties; however, there are limited data regarding its impact on host immune responses in vivo. We performed longitudinal and comprehensive immunosurveillance to assess the ability of pegylated (peg)-IFNλ to augment antiviral host immunity as part of a clinical trial assessing the efficacy of peg-IFNλ in chronic hepatitis B (CHB) patients. These patients were pretreated with directly acting antiviral therapy (entecavir) for 12 weeks with subsequent addition of peg-IFNλ for up to 32 weeks. In a subgroup of patients, the addition of peg-IFNλ provoked high serum levels of antiviral cytokine IL-18. We also observed the enhancement of natural killer cell polyfunctionality and the recovery of a pan-genotypic HBV-specific CD4+ T cells producing IFN-γ with maintenance of HBV-specific CD8+ T cell antiviral and cytotoxic activities. It was only in these patients that we observed strong virological control with reductions in both viral replication and HBV antigen levels. Here, we show for the first time that in vivo peg-IFNλ displays significant immunostimulatory properties with improvements in the main effectors mediating anti-HBV immunity. Interestingly, the maintenance in HBV-specific CD8+ T cells in the presence of peg-IFNλ is in contrast to previous studies showing that peg-IFNα treatment for CHB results in a detrimental effect on the functionality of this important antiviral T cell compartment.
Background: Hepatitis delta frequently leads to liver cirrhosis and hepatic decompensation. As treatment options are limited, there is a need for biomarkers to determine disease activity and to predict the risk of disease progression. We hypothesized that anti-HDV IgM could represent such a marker.
Methods: Samples of 120 HDV-infected patients recruited in an international multicenter treatment trial (HIDIT-2) were studied. Anti-HDV IgM testing was performed using ETI-DELTA-IGMK-2-assay (DiaSorin). In addition, fifty cytokines, chemokines and angiogenetic factors were measured using multiplex technology (Bio-Plex System). A second independent cohort of 78 patients was studied for the development of liver-related clinical endpoints (decompensation, HCC, liver transplantation or death; median follow up of 3.0 years, range 0.6–12).
Results: Anti-HDV IgM serum levels were negative in 18 (15%), low (OD<0.5) in 76 (63%), and high in 26 (22%) patients of the HIDIT-2 cohort. Anti-HDV IgM were significantly associated with histological inflammatory (p<0.01) and biochemical disease activity (ALT, AST p<0.01). HDV replication was independent from anti-HDV IgM, however, low HBV-DNA levels were observed in groups with higher anti-HDV IgM levels (p<0.01). While high IP-10 (CXCL10) levels were seen in greater groups of anti-HDV IgM levels, various other antiviral cytokines were negatively associated with anti-HDV IgM. Associations between anti-HDV IgM and ALT, AST, HBV-DNA were confirmed in the independent cohort. Clinical endpoints occurred in 26 anti-HDV IgM positive patients (39%) but in only one anti-HDV IgM negative individual (9%; p = 0.05).
Conclusions: Serum anti-HDV IgM is a robust, easy-to-apply and relatively cheap marker to determine disease activity in hepatitis delta which has prognostic implications. High anti-HDV IgM levels may indicate an activated interferon system but exhausted antiviral immunity.
Triple therapy of chronic hepatitis C virus (HCV) infection with boceprevir (BOC) or telaprevir (TVR) leads to virologic failure in many patients which is often associated with the selection of resistance-associated variants (RAVs). These resistance profiles are of importance for the selection of potential rescue treatment options. In this study, we sequenced baseline NS3 RAVs population-based and investigated the sensitivity of NS3 phenotypes in an HCV replicon assay together with clinical factors for a prediction of treatment response in a cohort of 165 German and Swiss patients treated with a BOC or TVR-based triple therapy. Overall, the prevalence of baseline RAVs was low, although the frequency of RAVs was higher in patients with virologic failure compared to those who achieved a sustained virologic response (SVR) (7% versus 1%, P = 0.06). The occurrence of RAVs was associated with a resistant NS3 quasispecies phenotype (P<0.001), but the sensitivity of phenotypes was not associated with treatment outcome (P = 0.2). The majority of single viral and host predictors of SVR was only weakly associated with treatment response. In multivariate analyses, low AST levels, female sex and an IFNL4 CC genotype were independently associated with SVR. However, a combined analysis of negative predictors revealed a significantly lower overall number of negative predictors in patients with SVR in comparison to individuals with virologic failure (P<0.0001) and the presence of 2 or less negative predictors was indicative for SVR. These results demonstrate that most single baseline viral and host parameters have a weak influence on the response to triple therapy, whereas the overall number of negative predictors has a high predictive value for SVR.
Background: Accurate assessment of hepatic fibrosis in patients with chronic HBeAg-negative Hepatitis B is of crucial importance not only to predict the long-term clinical course, but also to evaluate antiviral therapy indication. The aim of this study was to prospectively assess the utility of point shear wave elastography (pSWE) for longitudinal non-invasive fibrosis assessment in a large cohort of untreated patients with chronic HBeAg-negative hepatitis B virus (HBV) infection.
Methods: 407 consecutive patients with HBeAg-negative HBV infection who underwent pSWE, transient elastography (TE) as well as laboratory fibrosis markers, including fibrosis index based on four factors (FIB-4), aspartate to platelet ratio index (APRI) and FibroTest, on the same day were prospectively followed up for six years. Patients were classified into one of the three groups: inactive carriers (IC; HBV-DNA <2000 IU/mL and ALT <40 U/L); grey zone group 1 (GZ-1; HBV DNA <2000 IU/mL and ALT >40 U/L); grey zone group 2 (GZ-2; HBV-DNA >2000 IU/mL and ALT <40 U/L).
Results: pSWE results were significantly correlated with TE (r = 0.29, p < 0.001) and APRI (r = 0.17; p = 0.005). Median pSWE values did not differ between IC, GZ-1 and GZ-2 patients (p = 0.82, p = 0.17, p = 0.34). During six years of follow-up, median pSWE and TE values did not differ significantly over time (TE: p = 0.27; pSWE: p = 0.05).
Conclusion: Our data indicate that pSWE could be useful for non-invasive fibrosis assessment and follow-up in patients with HBeAg-negative chronic HBV infection.
Cholecystokinin (CCK) and related peptides are potent growth factors in the gastrointestinal tract and may be important for human cancer. CCK exerts its growth modulatory effects through G(q)-coupled receptors (CCK(A) and CCK(B)) and activation of extracellular signal-regulated protein kinase 1/2 (ERK1/2). In the present study, we investigated the different mechanisms participating in CCK-induced activation of ERK1/2 in pancreatic AR42J cells expressing both CCK(A) and CCK(B). CCK activated ERK1/2 and Raf-1 to a similar extent as epidermal growth factor (EGF). Inhibition of EGF receptor (EGFR) tyrosine kinase or expression of dominant-negative Ras reduced CCK-induced ERK1/2 activation, indicating participation of the EGFR and Ras in CCK-induced ERK1/2 activation. However, compared with EGF, CCK caused only small increases in tyrosine phosphorylation of the EGFR and Shc, Shc-Grb2 complex formation, and Ras activation. Signal amplification between Ras and Raf in a CCK-induced ERK cascade appears to be mediated by activation of protein kinase Cepsilon (PKCepsilon), because 1) down-modulation of phorbol ester-sensitive PKCs inhibited CCK-induced activation of Ras, Raf, and ERK1/2 without influencing Shc-Grb2 complex formation; 2) PKCepsilon, but not PKCalpha or PKCdelta, was detectable in Raf-1 immunoprecipitates, although CCK activated all three PKC isoenzymes. In addition, the present study provides evidence that the Src family tyrosine kinase Yes is activated by CCK and mediates CCK-induced tyrosine phosphorylation of Shc. Furthermore, we show that CCK-induced activation of the EGFR and Yes is achieved through the CCK(B) receptor. Together, our data show that different signals emanating from the CCK receptors mediate ERK1/2 activation; activation of Yes and the EGFR mediate Shc-Grb2 recruitment, and activation of PKC, most likely PKCepsilon, augments CCK-stimulated ERK1/2 activation at the Ras/Raf level.
Market uptake of pegylated interferons for the treatment of hepatitis C in Europe : meeting abstract
(2008)
Introduction and Objectives Hepatitis C virus (HCV) infection is a leading cause of chronic liver disease with life threatening sequelae such as end-stage liver cirrhosis and liver cancer. It is estimated that the infection annually causes about 86,000 deaths, 1.2 million disability adjusted life years (DALYs), and ¼ of the liver transplants in the WHO European region. Presently, only antiviral drugs can prevent the progression to severe liver disease. Pegylated interferons combined with ribavirin are considered as current state-of-the-art treatment. Objective of this investigation was to assess the market uptake of these drugs across Europe in order to find out whether there is unequal access to optimised therapy. Material and Methods We used IMS launch and sales data (April 2000 to December 2005) for peginterferons and ribavirin for 21 countries of the WHO European region. Market uptake was investigated by comparing the development of country-specific sales rates. For market access analysis, we converted sales figures into numbers of treated patients and related those to country-specific hepatitis C prevalence. To convert sales figures into patient figures, the amount of active pharmaceutical ingredients (API) sold was divided by average total patient doses (ATPD), derived by a probability tree-based calculation algorithm accounting for genotype distribution, early stopping rules, body weight, unscheduled treatment stops and dose reductions Ntotal=APIPegIFNalpha-2a/ATPDPegIFNalpha-2a+APIPegIFN&alpha-2b/ATPDPegIFNalpha-2b For more concise result presentation the 21 included countries were aggregated into four categories: 1. EU founding members (1957): Belgium, France, Germany, Italy and Netherlands; 2. Countries joining EU before 2000: Austria (1995), Denmark (1973), Finland (1995), Greece (1981), Republic of Ireland (1973), Spain (1986), Sweden and UK (1973) 3. Countries joining EU after 2000: Czech Republic (2004), Hungary (2004), Poland (2004) and Romania (2007); 4. EU non-member states: Norway, Russia, Switzerland and Turkey. Results Market launch and market uptake of the investigated drugs differed considerably across countries. The earliest, most rapid and highest increases in sales rates were observed in the EU founding member states, followed by countries that joined the EU before 2000, countries that joined the EU after 2000, and EU non-member states. Most new EU member states showed a noticeable increase in sales after joining the EU. Market access analysis yielded that until end of 2005, about 308 000 patients were treated with peginterferon in the 21 countries. Treatment rates differed across Europe. The number of patients ever treated with peginterferon per 100 prevalent cases ranged from 16 in France to less than one in Romania, Poland, Greece and Russia. Discussion Peginterferon market uptake and prevalence adjusted treatment rates were found to vary considerably across 21 countries in the WHO European region suggesting unequal access to optimised therapy. Poor market access was especially common in low-resource countries. Besides budget restrictions, national surveillance and prevention policy should be considered as explanations for market access variation. Although our results allowed for the ranking of countries in order of market access, no final conclusions on over- or undertreatment can be drawn, because the number of patients who really require antiviral treatment is unknown. Further research based on pan-European decision models is recommended to determine the fraction of not yet successfully treated but treatable patients among those ever diagnosed with HCV. ...
Background Hepatitis C virus (HCV) is a leading cause of chronic liver disease, end-stage cirrhosis, and liver cancer, but little is known about the burden of disease caused by the virus. We summarised burden of disease data presently available for Europe, compared the data to current expert estimates, and identified areas in which better data are needed. Methods Literature and international health databases were systematically searched for HCV-specific burden of disease data, including incidence, prevalence, mortality, disability-adjusted life-years (DALYs), and liver transplantation. Data were collected for the WHO European region with emphasis on 22 countries. If HCV-specific data were unavailable, these were calculated via HCV-attributable fractions. Results HCV-specific burden of disease data for Europe are scarce. Incidence data provided by national surveillance are not fully comparable and need to be standardised. HCV prevalence data are often inconclusive. According to available data, an estimated 7.3–8.8 million people (1.1–1.3%) are infected in our 22 focus countries. HCV-specific mortality, DALY, and transplantation data are unavailable. Estimations via HCV-attributable fractions indicate that HCV caused more than 86000 deaths and 1.2 million DALYs in the WHO European region in 2002. Most of the DALYs (95%) were accumulated by patients in preventable disease stages. About one-quarter of the liver transplants performed in 25 European countries in 2004 were attributable to HCV. Conclusion Our results indicate that hepatitis C is a major health problem and highlight the importance of timely antiviral treatment. However, data on the burden of disease of hepatitis C in Europe are scarce, outdated or inconclusive, which indicates that hepatitis C is still a neglected disease in many countries. What is needed are public awareness, co-ordinated action plans, and better data. European physicians should be aware that many infections are still undetected, provide timely testing and antiviral treatment, and avoid iatrogenic transmission.
Background: High baseline levels of IP-10 predict a slower first phase decline in HCV RNA and a poor outcome following interferon/ribavirin therapy in patients with chronic hepatitis C. Several recent studies report that single nucleotide polymorphisms (SNPs) adjacent to IL28B predict spontaneous resolution of HCV infection and outcome of treatment among HCV genotype 1 infected patients. Methods and Findings: In the present study, we correlated the occurrence of variants at three such SNPs (rs12979860, rs12980275, and rs8099917) with pretreatment plasma IP-10 and HCV RNA throughout therapy within a phase III treatment trial (HCV-DITTO) involving 253 Caucasian patients. The favorable SNP variants (CC, AA, and TT, respectively) were associated with lower baseline IP-10 (P = 0.02, P = 0.01, P = 0.04) and were less common among HCV genotype 1 infected patients than genotype 2/3 (P<0.0001, P<0.0001, and P = 0.01). Patients carrying favorable SNP genotypes had higher baseline viral load than those carrying unfavorable variants (P = 0.0013, P = 0.029, P = 0.0004 respectively). Among HCV genotype 1 infected carriers of the favorable C, A, or T alleles, IP-10 below 150 pg/mL significantly predicted a more pronounced reduction of HCV RNA from day 0 to 4 (first phase decline), which translated into increased rates of RVR (62%, 53%, and 39%) and SVR (85%, 76%, and 75% respectively) among homozygous carriers with baseline IP-10 below 150 pg/mL. In multivariate analyses of genotype 1-infected patients, baseline IP-10 and C genotype at rs12979860 independently predicted the first phase viral decline and RVR, which in turn independently predicted SVR. Conclusions: Concomitant assessment of pretreatment IP-10 and IL28B-related SNPs augments the prediction of the first phase decline in HCV RNA, RVR, and final therapeutic outcome.
Chronic hepatitis C is a major reason for development of cirrhosis and hepatocellular carcinoma and a leading cause for liver transplantation. The development of direct-acting antiviral agents lead to (pegylated) interferon-alfa free antiviral therapy regimens with a remarkable increase in sustained virologic response (SVR) rates and opened therapeutic options for patients with advanced cirrhosis and liver graft recipients. This concise review gives an overview about most current prospective trials and cohort analyses for treatment of patients with liver cirrhosis and liver graft recipients. In patients with compensated cirrhosis Child-Pugh-Turcotte (CTP) class A, all approved agents are safe and SVR rates do not significantly differ from patients without cirrhosis in general. In patients with decompensated cirrhosis CTP class B or C, daclastasvir, ledipasvir, velpatasvir, and sofosbuvir are approved, and SVR rates higher than 90% can be achieved. Especially for patients with a model of end stage liver disease score higher than 15 and therefore eligible for liver transplantation, data is scarce. Reported SVR rates in patients with cirrhosis CTP class C are lower compared to patients with a less severe liver disease. In liver transplant recipients with a maximum of CTP class A, SVR rates are comparable to patients without LT. Patients with decompensated graft cirrhosis should be treated on an individual basis.
Background: Interferon and ribavirin therapy for chronic hepatitis C virus (HCV) infection yields sustained virological response (SVR) rates of 50–80%. Several factors such as non-1 genotype, beneficial IL28B genetic variants, low baseline IP-10, and the functionality of HCV-specific T cells predict SVR. With the pending introduction of new therapies for HCV entailing very rapid clearance of plasma HCV RNA, the importance of baseline biomarkers likely will increase in order to tailor therapy. CD26 (DPPIV) truncates the chemokine IP-10 into a shorter antagonistic form, and this truncation of IP-10 has been suggested to influence treatment outcome in patients with chronic HCV infection patients. In addition, previous reports have shown CD26 to be a co-stimulator for T cells. The aim of the present study was to assess the utility of CD26 as a biomarker for treatment outcome in chronic hepatitis C and to define its association with HCV-specific T cells.
Methods: Baseline plasma from 153 genotype 1 and 58 genotype 2/3 infected patients enrolled in an international multicenter phase III trial (DITTO-HCV) and 36 genotype 1 infected patients participating in a Swedish trial (TTG1) were evaluated regarding baseline soluble CD26 (sCD26) and the functionality of HCV-specific CD8+ T cells.
Results: Genotype 1 infected patients achieving SVR in the DITTO (P = 0.002) and the TTG1 (P = 0.02) studies had lower pretreatment sCD26 concentrations compared with non-SVR patients. Sixty-five percent of patients with sCD26 concentrations below 600 ng/mL achieved SVR compared with 39% of the patients with sCD26 exceeding 600 ng/mL (P = 0.01). Patients with sCD26 concentrations below 600 ng/mL had significantly higher frequencies of HCV-specific CD8+ T cells (P = 0.02).
Conclusions: Low baseline systemic concentrations of sCD26 predict favorable treatment outcome in chronic HCV infection and may be associated with higher blood counts of HCV-specific CD8+ T cells.
Different highly effective interferon-free treatment options for chronic hepatitis C virus (HCV) infection are currently available. Pre-existence of resistance associated variants (RAVs) to direct antiviral agents (DAAs) reduces sustained virologic response (SVR) rates by 3–53% in hepatitis C virus (HCV) genotype 1 infected patients depending on different predictors and the DAA regimen used. Frequencies of single and combined resistance to NS3, NS5A and NS5B inhibitors and consequences for the applicability of different treatment regimens are unknown. Parallel population based sequencing of HCV NS3, NS5A and NS5B genes in 312 treatment-naïve Caucasian HCV genotype 1 infected patients showed the presence of major resistant variants in 20.5% (NS3), 11.9% (NS5A), and 22.1% (NS5B) with important differences for HCV subtypes. In NS3, Q80K was observed in 34.7% and 2.1% of subtype 1a and 1b patients, respectively while other RAVs to second generation protease inhibitors were detected rarely (1.4%). Within NS5A RAVs were observed in 7.1% of subtype 1a and 17.6% in subtype 1b infected patients. RAVs to non-nucleoside NS5B inhibitors were observed in 3.5% and 44.4% of subtype 1a and 1b patients, respectively. Considering all three DAA targets all subtype 1a and 98.6% of subtype 1b infected patients were wildtype for at least one interferon free DAA regimen currently available. In conclusion, baseline resistance testing allows the selection of at least one RAVs-free treatment option for nearly all patients enabling a potentially cost- and efficacy-optimized treatment of chronic hepatitis C.
Interleukin-7 (IL-7) is an important cytokine with pivotal pro-survival functions in the adaptive immune system. However, the role of IL-7 in innate immunity is not fully understood. In the present study, the impact of hepatic IL-7 on innate immune cells was assessed by functional experiments as well as in patients with different stages of liver cirrhosis or acute-on-chronic liver failure (ACLF). Human hepatocytes and liver sinusoidal endothelial cells secreted IL-7 in response to stimulation with interferons (IFNs) of type I and II, yet not type III. De novo translation of interferon-response factor-1 (IRF-1) restricted IL-7 production to stimulation with type I and II IFNs. LPS-primed human macrophages were identified as innate immune target cells responding to IL-7 signaling by inactivation of Glycogen synthase kinase-3 (GSK3). IL-7-mediated GSK3 inactivation augmented LPS-induced secretion of pro-inflammatory cytokines and blunted LPS tolerance of macrophages. The IFN-IRF-1-IL-7 axis was present in liver cirrhosis patients. However, liver cirrhosis patients with or without ACLF had significantly lower concentrations of IL-7 in serum compared to healthy controls, which might contribute to LPS-tolerance in these patients. In conclusion, we propose the presence of an inflammatory cascade where IFNs of type I/II induce hepatocellular IL-7 in an IRF-1-restriced way. Beyond its role in adaptive immune responses, IL-7 appears to augment the response of macrophages to LPS and to ameliorate LPS tolerance, which may improve innate immune responses against invading pathogens.
Extracellular vesicles (EVs) are increasingly recognized as important mediators of intercellular communication. In this study, we aimed to further characterize the role of macrophage-derived EVs in immune responses against hepatitis C virus (HCV) and the potential of polyunsaturated fatty acids (PUFAs) to modulate this modality of innate immunity. To this end, EVs were isolated from interferon-stimulated macrophage cultures or from serum of patients with acute or chronic hepatitis C. EVs were characterized by electron microscopy, flow cytometry, RNA-sequencing, and Western blot analysis. The effect of EVs on replication of HCV was assessed in coculture models. Functional analyses were performed to assess the impact of PUFAs on EV-mediated antiviral immunity. We found that macrophages secreted various cytokines shortly after stimulation with type I and II IFN, which orchestrated a fast but short-lasting antiviral state. This rapid innate immune answer was followed by the production of macrophage-derived EVs, which induced a late, but long-lasting inhibitory effect on HCV replication. Of note, exposure of macrophages to PUFAs, which are important regulators of immune responses, dampened EV-mediated antiviral immune responses. Finally, EVs from patients with hepatitis C exhibited long-lasting antiviral activities during IFN therapy as well. The antiviral effect of EVs from Caucasian and Japanese patients differed, which may be explained by different nutritional uptake of PUFAs. In conclusion, our data indicate that macrophage-derived EVs mediate long-lasting inhibitory effects on HCV replication, which may bridge the time until efficient adaptive immune responses are established, and which can be blunted by PUFAs.
The human DNA mismatch repair (MMR) process is crucial to maintain the integrity of the genome and requires many different proteins which interact perfectly and coordinated. Germline mutations in MMR genes are responsible for the development of the hereditary form of colorectal cancer called Lynch syndrome. Various mutations mainly in two MMR proteins, MLH1 and MSH2, have been identified so far, whereas 55% are detected within MLH1, the essential component of the heterodimer MutLα (MLH1 and PMS2). Most of those MLH1 variants are pathogenic but the relevance of missense mutations often remains unclear. Many different recombinant systems are applied to filter out disease-associated proteins whereby fluorescent tagged proteins are frequently used. However, dye labeling might have deleterious effects on MutLα's functionality. Therefore, we analyzed the consequences of N- and C-terminal fluorescent labeling on expression level, cellular localization and MMR activity of MutLα. Besides significant influence of GFP- or Red-fusion on protein expression we detected incorrect shuttling of single expressed C-terminal GFP-tagged PMS2 into the nucleus and found that C-terminal dye labeling impaired MMR function of MutLα. In contrast, N-terminal tagged MutLαs retained correct functionality and can be recommended both for the analysis of cellular localization and MMR efficiency.
Introduction: Defects in the DNA mismatch repair (MMR) protein MLH1 are frequently observed in sporadic and hereditary colorectal cancers (CRC). Affected tumors generate much less metastatic potential than the MLH1 proficient forms. Although MLH1 has been shown to be not only involved in postreplicative MMR but also in several MMR independent processes like cytoskeletal organization, the connection between MLH1 and metastasis remains unclear. We recently identified non-erythroid spectrin αII (SPTAN1), a scaffolding protein involved in cell adhesion and motility, to interact with MLH1. In the current study, the interaction of MLH1 and SPTAN1 and its potential consequences for CRC metastasis was evaluated.
Methods: Nine cancer cell lines as well as fresh and paraffin embedded colon cancer tissue from 12 patients were used in gene expression studies of SPTAN1 and MLH1. Co-expression of SPTAN1 and MLH1 was analyzed by siRNA knock down of MLH1 in HeLa, HEK293, MLH1 positive HCT116, SW480 and LoVo cells. Effects on cellular motility were determined in MLH1 deficient HCT116 and MLH1 deficient HEK293T compared to their MLH1 proficient sister cells, respectively.
Results: MLH1 deficiency is clearly associated with SPTAN1 reduction. Moreover, siRNA knock down of MLH1 decreased the mRNA level of SPTAN1 in HeLa, HEK293 as well as in MLH1 positive HCT116 cells, which indicates a co-expression of SPTAN1 by MLH1. In addition, cellular motility of MLH1 deficient HCT116 and MLH1 deficient HEK293T cells was impaired compared to the MLH1 proficient sister clones. Consequently, overexpression of SPTAN1 increased migration of MLH1 deficient cells while knock down of SPTAN1 decreased cellular mobility of MLH1 proficient cells, indicating SPTAN1-dependent migration ability.
Conclusions: These data suggest that SPTAN1 levels decreased in concordance with MLH1 reduction and impaired cellular mobility in MLH1 deficient colon cancer cells. Therefore, aggressiveness of MLH1-positive CRC might be related to SPTAN1.
Background: Hepatitis C virus (HCV) is currently classified into 8 genotypes and 86 subtypes. The objective of this study was to characterize novel HCV subtypes and to investigate the impact of subtypes on treatment outcome.
Methods: Full-genome sequencing was performed on HCV plasma samples with <85% sequence homology of NS3, NS5A, and/or NS5B to HCV genotype (GT) 1–8 reference strains.
Results: A total of 14 653 patients with GT1–6 HCV infection were enrolled in clinical studies of sofosbuvir-based regimens. For the majority of the patients, a specific subtype could be assigned based on a close genetic relationship to previously described subtypes. However, for 19 patients, novel subtypes were identified with <85% homology compared with previously described subtypes. These novel subtypes had the following genotypes: 9 in GT2, 5 in GT4, 2 in GT6, and 1 each in GT1, GT3, and GT5. Despite the presence of polymorphisms at resistance-associated substitution positions, 18 of the 19 patients treated with sofosbuvir-containing therapy achieved SVR12.
Conclusions: Nineteen novel HCV subtypes were identified, suggesting an even greater genetic diversity of HCV subtypes than previously recognized.
Background & aims: Vitamin D, best known to regulate bone mineralization, has numerous additional roles including regulation inflammatory pathways. Recently, an increased incidence of 25-hydroxyvitamin D3 (25(OH)D3) deficiency has been found in subjects suffering from liver diseases. We here investigated if low vitamin D levels might be associated with prognosis, inflammation and infectious complications in patients with cirrhosis.
Methods: We performed a prospective cohort study investigating the relation between 25(OH)D3 levels and stages of cirrhosis, mortality and complications of cirrhosis, including infections.
Results: 251 patients with cirrhosis were enrolled into the present prospective cohort study. 25(OH)D3 levels were quantified by radioimmunoassay from serum samples obtained at study inclusion. The mean follow-up time was 411 ± 397 days with a range of 1-1382 days. 30 (12.0%) patients underwent liver transplantation and 85 (33.8%) individuals died within the study. The mean serum 25(OH)D3 concentration was 8.93 ± 7.1 ng/ml with a range of 1.0 to 46.0 ng/ml. 25(OH)D3 levels differed significantly between Child Pugh scores and showed a negative correlation with the model of end stage liver disease (MELD) score. Patients with decompensated cirrhosis and infectious complications, had significantly lower 25(OH)D3 levels compared to subjects without complications. Low 25(OH)D3 was associated with mortality in uni- as well as multivariate Cox regression models.
Conclusions: 25(OH)D3 deficiency is associated with advanced liver disease and low 25(OH)D3 levels are an indicator for a poor outcome and are associated with infectious complications.
Objectives: Rising prevalence of multidrug-resistant organisms (MDRO) is a major health problem in patients with liver cirrhosis. The impact of MDRO colonization in liver transplantation (LT) candidates and recipients on mortality has not been determined in detail.
Methods: Patients consecutively evaluated and listed for LT in a tertiary German liver transplant center from 2008 to 2018 underwent screening for MDRO colonization including methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant gram-negative bacteria (MDRGN), and vancomycin-resistant enterococci (VRE). MDRO colonization and infection status were obtained at LT evaluation, planned and unplanned hospitalization, three months upon graft allocation, or at last follow-up on the waiting list.
Results: In total, 351 patients were listed for LT, of whom 164 (47%) underwent LT after a median of 249 (range 0–1662) days. Incidence of MDRO colonization increased during waiting time for LT, and MRDO colonization was associated with increased mortality on the waiting list (HR = 2.57, p<0.0001. One patients was colonized with a carbapenem-resistant strain at listing, 9 patients acquired carbapenem-resistant gram-negative bacteria (CRGN) on the waiting list, and 4 more after LT. In total, 10 of these 14 patients died.
Conclusions: Colonization with MDRO is associated with increased mortality on the waiting list, but not in short-term follow-up after LT. Moreover, colonization with CRGN seems associated with high mortality in liver transplant candidates and recipients.
Hepatocellular carcinoma (HCC) shows a remarkable heterogeneity and is recognized as a chemoresistant tumor with dismal prognosis. In previous studies, we observed significant alterations in the serum sphingolipids of patients with HCC. This study aimed to investigate the in vitro effects of sorafenib, which is the most widely used systemic HCC medication, on the sphingolipid pathway as well as the effects of inhibiting the sphingolipid pathway in HCC. Huh7.5 and HepG2 cells were stimulated with sorafenib, and inhibitors of the sphingolipid pathway and cell proliferation, viability, and concentrations of bioactive metabolites were assessed. We observed a significant downregulation of cell proliferation and viability and a simultaneous upregulation of dihydroceramides upon sorafenib stimulation. Interestingly, fumonisin B1 (FB1) and the general sphingosine kinase inhibitor SKI II were able to inhibit cell proliferation more prominently in HepG2 and Huh7.5 cells, whereas there were no consistent effects on the formation of dihydroceramides, thus implying an involvement of distinct metabolic pathways. In conclusion, our study demonstrates a significant downregulation of HCC proliferation upon sorafenib, FB1, and SKI II treatment, whereas it seems they exert antiproliferative effects independently from sphingolipids. Certainly, further data would be required to elucidate the potential of FB1 and SKI II as putative novel therapeutic targets in HCC.
Epigenetic silencing of tumour suppressor genes has been observed in various cancers. Looking at hepatocellular carcinoma (HCC) specific protein silencing was previously demonstrated to be associated with the Hepatitis C virus (HCV). However, the proposed HCV dependent promoter methylation of DNA mismatch repair (MMR) genes and thereby enhanced progression of hepatocarcinogenesis has been the subject of controversial discussion. We investigated promoter methylation pattern of the MMR genes MLH1, MSH2 and PMS2 as well as the cyclin-dependent kinase inhibitor 2A gene (p16) in 61 well characterized patients with HCCs associated with HCV, Hepatitis B virus infection or alcoholic liver disease. DNA was isolated from formalin-fixed, paraffin-embedded tumour and non-tumour adjacent tissue and analysed by methylation-specific PCR. Moreover, microsatellite analysis was performed in tissues showing methylation in MMR gene promoters. Our data demonstrated that promoter methylation of MLH1, MSH2, PMS2 and p16 is present among all considered HCCs. Hereby, promoter silencing was detectable more frequently in advanced-stage HCCs than in low-stage ones. However, there was no significant correlation between aberrant DNA methylation of MMR genes or p16 and HCV infection in related HCC specimens. In summary, we show that promoter methylation of essential MMR genes and p16 is detectable in HCCs most dominantly in pT3 stage tumour cases. Since loss of MMR proteins was previously described to be not only responsible for tumour development but also for chemotherapy resistance, the knowledge of mechanisms jointly responsible for HCC progression might enable significant improvement of individual HCC therapy in the future.