Long-term effects of interferon therapy on histology and development of hepatocellular carcinoma in hepatitis C

Toll-like receptor 7-mediated type I interferon signaling prevents cholestasis- and hepatotoxin-induced liver fibrosis

Toll-like receptor 7 (TLR7) signaling predominantly regulates production of type I interferons (IFNs), which has been suggested in clinical studies to be antifibrotic. However, the mechanistic role of the TLR7-type I IFN axis in liver fibrosis has not been elucidated. In the present study, liver fibrosis was induced in wild-type (WT), TLR7-deficient, and IFN-α/β receptor-1 (IFNAR1)-deficient mice and TLR7-mediated signaling was assessed in liver cells isolated from these mice. TLR7-deficient and IFNAR1-deficient mice were more susceptible to liver fibrosis than WT mice, indicating that TLR7-type I IFN signaling exerts a protective effect against liver fibrosis. Notably, the hepatic expression of interleukin-1 receptor antagonist (IL-1ra) was suppressed in TLR7- or IFNAR1-deficient mice compared with respective WT mice, and treatment with recombinant IL-1ra reduced liver fibrosis. In vivo activation of TLR7 significantly increased IFNa4 and IL-1ra expression in the liver. Interestingly, each cytokine had a different cellular source, showing that dendritic cells (DCs) are the responsible cell type for production of type I IFN, while Kupffer cells (KCs) mainly produce IL-1ra in response to type I IFN. Furthermore, TLR7 activation by R848 injection suppressed liver fibrosis and production of proinflammatory cytokines, and these effects were dependent on type I IFN signaling. Consistent with in vivo data, IFN-α significantly induced IL-1ra production in primary KCs.

CONCLUSION

TLR7 signaling activates DCs to produce type I IFN, which in turn induces antifibrogenic IL-1ra production in KCs. Thus, manipulation of the TLR7-type I IFN-IL-1ra axis may be a new therapeutic strategy for the treatment of liver fibrosis.

Patients' preferences for treatment of hepatitis C

BACKGROUND

The objective of this study was to ascertain patient preferences for treatment of hepatitis C virus (HCV).

METHODS

The authors recruited consecutive patients eligible for treatment of HCV and used adaptive conjoint analysis (ACA), a hybrid approach of conjoint analysis that uses both self-explicated ratings and pair-wise comparisons, to elicit preferences for pegylated-interferon and ribavirin. They examined the association between patient characteristics and treatment preferences using the Mann-Whitney U test and chi(2) statistic for continuous and categorical variables, respectively, and subsequently calculated adjusted odds ratios and 95% confidence intervals using logistic regression.

RESULTS

A total of 140 subjects completed the ACA task. The mean (+/-SD) age of the sample was 51+/-8 y; 85% were male, and 59% were white. When described as being associated with mild side effects, 67% (n = 94) of subjects preferred treatment for HCV. The percentage of subjects preferring therapy decreased to 51% (n = 72) when it was described as being associated with severe side effects. Preferences for treatment of HCV were stronger among subjects with a higher perceived risk of developing cirrhosis, more severe underlying liver disease, and worse HCV-related quality of life. Subjects having more severe disease placed greater weight on the importance of expected benefits and less on the risk of toxicity compared with those with mild or no fibrosis.

CONCLUSIONS

Whether to choose treatment for HCV is a difficult decision for many patients. Treatment is usually recommended for those with moderate to severe liver disease, and these results demonstrate that most patients' preferences are concordant with this practice.

Hepatitis C: current options for nonresponders to peginterferon and ribavirin

Hepatitis C virus infection remains a significant health problem worldwide. The development of interferon-based therapies has led to increased success in eradicating this viral infection; however, no recent additions to the current treatment care regimen (peginterferon and ribavirin) have been made. Nonresponders to peginterferon/ribavirin make up a diverse patient population that can be difficult to manage. Through a better understanding of treatment response and viral kinetics, clinicians are employing altered dosing schedules to minimize the burden of viral illness. Consequently, clinicians can now manage nonresponders by providing supportive care and reserving retreatment for those most likely to respond to additional antiviral therapy, particularly when correctable factors from a previous treatment course with the potential for positive intervention have been identified. The decision for further medical management is based on clinical and laboratory parameters that have been shown to predict which patients will benefit most from another attempt at therapy.

Interferon-beta reduces the mouse liver fibrosis induced by repeated administration of concanavalin A via the direct and indirect effects

Type I interferons (IFNs), IFN-alpha and IFN-beta, are widely used for treating chronic hepatitis C. Although retrospective studies have suggested that type I IFNs have direct antifibrotic effects, little is known about these mechanisms. The present study was designed to clarify the preventive mechanisms of type I IFNs in the progression of fibrosis for the establishment of a more effective therapy. A murine fibrosis model comprising immunological reactions was induced by the administration of concanavalin A (0.3 mg/body) into mice once a week for 4 weeks. Liver injury and the degree of fibrosis were determined by measuring the serum alanine aminotransferase activities and liver hydroxyproline contents with or without IFN-beta pretreatment. IFN-beta suppressed the hepatocellular injury and increased the hydroxyproline content induced by repeated concanavalin A injections, but had no effect on established fibrosis. Furthermore, IFN-beta reduced the expressions of transforming growth factor-beta, basic fibroblast growth factor, collagen type I A2 and tissue inhibitor of metalloproteinase 1 messenger RNAs, which are related to the progression of liver fibrosis. The IFN-beta reduced the liver injury and fibrosis induced by immunological reactions. These data suggest that type I IFNs suppress the progression of cirrhosis through inhibition of repeated hepatocellular injury and/or factors that promote the liver fibrosis induced by hepatitis virus infection.

Patients' experiences related to anti-viral treatment for hepatitis C

OBJECTIVE

To conduct a qualitative study to elicit patients' descriptions of their own experiences with treatment for hepatitis C (HCV).

METHODS

Focus groups were conducted until thematic saturation was reached.

RESULTS

A total of 40 patients (80% male) participated in eight focus groups. The themes that emerged most frequently during the focus groups centered on adverse effects and quality of care. The discussions highlighted discrepancies between patients' anticipated effects of drug toxicity versus their actual experiences, gaps in communication between physicians, and the lack of social support as important shortcomings in the healthcare of HCV patients.

CONCLUSIONS

The issues raised by the participants in this study highlight several important areas that may lead to improved care for patients with HCV.

PRACTICE IMPLICATIONS

This study suggests that care for patients with HCV might be improved by using patient testimonials to improve accuracy of expectations, having both the primary care physician and liver specialist devise a plan to treat symptoms arising during the course of therapy, and ensuring that patients have the option of participating in a support group.

Early liver cancer: concepts, diagnosis, and management

Hepatocellular carcinoma is a major health problem worldwide. The prognosis of patients depends on the stage when the disease is diagnosed. For the early detection of these tumors, both the selection of patients at high risk and effective surveillance programs are important. When the tumor is diagnosed early, patients can choose potentially curative treatment, including surgical resection, transplantation, and ablation therapy. Here, we give an overview of the present management of hepatocellular carcinoma. Further studies in diagnosis, treatment, and prevention are required to achieve the best clinical management of this disease.

Noninvasive estimation of liver fibrosis and response to interferon therapy by a serum fibrogenesis marker, YKL-40, in patients with HCV-associated liver disease

AIM: To evaluate the clinical utility of serum fibrosis markers, including YKL-40, in patients with HCV-associated liver disease.

METHODS: A total of 109 patients with HCV-associated liver disease were enrolled. We measured serum type IV collagen, amino-terminal peptide of type III procollagen (PIIIP), hyaluronic acid (HA), YKL-40 levels and biochemical. Parameters by RIA or ELISA. Eighty-eight patients underwent liver biopsy, and 67 of 109 patients received interferon (IFN) therapy. We also investigated the relationship between the concentrations of serum fibrosis markers and histological fibrosis scores (METAVIR), and evaluated the changes of the levels of fibrosis markers before and after the IFN therapy.

RESULTS: The increase in serum levels of all markers, particularly HA, was correlated with the progression of liver fibrosis (for type IV collagen, F = 9.076, P<0.0001; for PIIIP, F = 9.636, P<0.0001; for HA, F = 13.128, P<0.0001; and for YKL-40, F = 8.016, P<0.0001). YKL-40 had strong correlation with HA (r = 0.536, P<0.0001). Based on the receiver operating curve (ROC), the ability of serum HA exceeded the abilities of other serum markers to determine fibrosis score 4 from fibrosis score 0-3 (AUC = 0.854). While YKL-40 was superior to other fibrosis markers for predicting severe fibrosis (F2-F4) from mild fibrosis (F0-F1) (YKL-40, AUC = 0.809; HA, AUC = 0.805). After IFN therapy, only YKL-40 values significantly decreased not only in the responder group, but also in the nonresponder group (P = 0.03).

CONCLUSION: YKL-40 may be a useful non-invasive serum marker to estimate the degree of liver fibrosis and to evaluate the efficacy of IFN therapies in patients with HCV-associated liver disease.

Management of chronic hepatitis C virus infection: a new era of disease control

The management of chronic viral hepatitis has changed significantly with the availability of effective antiviral agents. There is now a high probability that timely intervention can arrest development of cirrhosis, thereby preventing mortality from portal hypertension, liver failure and liver cancer. This two-part review discusses the implications of this new era of antiviral therapy for physicians. The present review is about chronic hepatitis C virus (HCV); a similar review that considers the treatment of hepatitis B virus will be published in a later issue of the Internal Medicine Journal. Chronic HCV infection is common, but fibrotic progression of liver disease is slow and variable; many infected persons never develop cirrhosis. Case selection for antiviral therapy is crucial. The most effective therapy is a pegylated (long-acting) interferon with ribavirin. Sustained viral response (SVR) (absent viraemia 6 months after completing treatment) can be obtained in 40-60% of individuals infected with genotype 1 and in approximately 67% with genotype 4 after 12 months of treatment. Response rates are higher (75-85%) with genotypes 2 and 3 after only 6 months of treatment. Late relapse is negligible after SVR. This viral cure reverses hepatic fibrosis, reduces the risk of liver failure and of hepato-cellular carcinoma. Combination therapy requires a supportive setting to minimize the impact of side-effects and maximize therapeutic effectiveness. Overall management of HCV-infected persons must also embrace measures to improve quality of life by preventing or dealing with psychosocial issues and advocating lifestyle changes to counter comorbidity from alcohol, central obesity and insulin resistance. These latter factors favour fibrotic disease progression, complications of cirrhosis (such as hepatocellular carcinoma) and development of type 2 diabetes mellitus, as well as eroding the chances of SVR with antiviral therapy.

Transforming growth factor-beta 1-induced apoptosis is blocked by beta 1-integrin-mediated mitogen-activated protein kinase activation in human hepatoma cells

Growth factors and extracellular matrices cooperatively regulate cellular behavior. However, the interactions between transforming growth factor-beta 1 (TGF-beta 1) and integrins in hepatic cells are not fully understood. We investigated the effects of beta 1-integrin on TGF-beta 1-regulated growth of hepatoma cells. Human hepatoma cell lines HepG2, Huh7, and Hep3B were stably transfected with beta 1-integrin, and the parental, and mock- and beta 1-integrin-transfected hepatoma cells were treated with TGF-beta 1. Modulation of apoptosis and pathways involved in the process were investigated. TGF-beta 1 suppressed the growth of hepatoma cells, and apoptosis was observed in Hep3B and Huh7. Hepatoma cells transfected with beta 1-integrin were protected from TGF-beta 1-induced apoptosis. Mitogen-activated protein (MAP) kinase inhibitors, PD98059, SB203580, and SP600125, abolished this protective effect of beta 1-integrin, but herbimycin A and wortmannin were ineffective. Hepatoma cells overexpressing beta 1-integrin showed increased activities of MAP kinases, and TGF-beta 1 induced sustained activation of MAP kinases in these cells, but only transient activation in mock-transfected cells. These data suggest that MAP kinases activated by beta 1-integrin provide a strong anti-apoptotic signal during TGF-beta 1-induced apoptosis in human hepatoma cells. Therefore beta 1-integrin-mediated signals may contribute to the development and progression of hepatocellular carcinoma.

Evolution of the HALT-C Trial: pegylated interferon as maintenance therapy for chronic hepatitis C in previous interferon nonresponders

The Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial was designed to determine whether maintenance interferon therapy could slow disease progression in patients who had failed to eradicate hepatitis C virus (HCV) during prior interferon treatment (nonresponders). Ten clinical sites, a virological testing center, and a data coordinating center (DCC) were selected to collaborate in the design and implementation of the final protocol. Eligible patients had been treated previously with interferon for at least 12 weeks, with or without another antiviral, ribavirin, but still had persistent viremia. Because patients had received a variety of prior treatments, and as a perceived benefit of enrollment, we incorporated a Lead-in period of treatment with long-acting pegylated interferon alfa-2a plus ribavirin into the study design, a combination believed to be more effective but not approved by the Food and Drug Administration at the Trial's inception. If patients failed to achieve clearance of virus from the blood after 20 weeks of this Lead-in therapy, they were entered into the main trial at week 24 and randomized to receive either a lower dose of pegylated interferon weekly alone or no further therapy for an additional 3 1/2 years. The original protocol was amended later in three respects to improve enrollment and to adapt to Food and Drug Administration approval of the Lead-in therapy, including allowing patients to proceed directly to the randomized part of the study if treatment resembling the Lead-in had been completed. The protocol changes enhanced enrollment while upholding the original goals of the study and its integrity.

Maintenance therapy with ribavirin in patients with chronic hepatitis C who fail to respond to combination therapy with interferon alfa and ribavirin

To assess the efficacy and safety of maintenance therapy with ribavirin alone in chronic hepatitis C, 108 patients were treated with the combination of interferon alfa and ribavirin for 24 weeks; those who failed to have a virologic response were offered enrollment in a randomized, double-blind, controlled trial of ribavirin (1,000-1,200 mg daily) versus placebo for the subsequent 48 weeks. Patients were monitored at regular intervals with symptom questionnaires, serum aminotransferase levels, hepatitis C virus (HCV) RNA levels, and complete blood counts and underwent liver biopsy at the completion of therapy. Among 108 patients, 50 were still HCV RNA positive after 24 weeks of treatment, of whom 34 agreed to be randomized to continue either ribavirin monotherapy or placebo. Among 17 patients who received placebo, there was no overall improvement in symptoms, serum alanine aminotransferase (ALT) levels, HCV RNA levels, or hepatic histology. Among the 17 patients who received ribavirin, serum ALT levels and necroinflammatory features of liver histology were improved, whereas symptoms, HCV RNA levels, and hepatic fibrosis scores were not changed significantly from baseline. Responses to ribavirin seemed to be categorical, such that 8 patients (47%) had definite improvement in liver histology. Patients with improved histology had improvements in serum ALT levels both on combination therapy and after switching to ribavirin monotherapy. In conclusion, continuation of ribavirin monotherapy may maintain serum biochemical improvements that occur during interferon-ribavirin combination therapy in some patients and that these improvements are often associated with decreases in necroinflammatory changes in the liver. Whether these improvements will ultimately result in prevention of progression of hepatitis C requires further study.

Hepatitis C in clinical practice

Hepatitis C virus infection is now one of the most important causes of chronic liver disease. Primary care physicians play an important role in the diagnosis and initial work-up of patients infected with this virus. Understanding which patients may be at risk is the first step. By understanding the correct use of hepatitis C virus diagnostic testing and the risk and benefits of antiviral therapy, providers will be better equipped to screen and counsel their patients.