Effects of interferon therapy on development of hepatocellular carcinoma in patients with hepatitis C-related cirrhosis: A meta-analysis of randomized controlled trials

Chapter XX Antiviral Treatment and Cancer Control

Hepatitis B virus (HBV), hepatitis C virus (HCV), human papilloma virus (HPV), Epstein-Barr virus (EBV), human T-cell lymphotropic virus type 1 (HTLV-1), Kaposi's sarcoma-associated herpesvirus (KSHV), and Merkel cell polyomavirus (MCV) contribute to about 10-15% global burden of human cancers. Conventional chemotherapy or molecular target therapies have been used to treat virus-associated cancers. However, a more proactive approach would be the use of antiviral treatment to suppress or eliminate viral infections to prevent the occurrence of cancer in the first place. Antiviral treatments against chronic HBV and HCV infection have achieved this goal, with significant reduction in the incidence of hepatocellular carcinoma in treated patients. Antiviral treatments for EBV, KSHV, and HTLV-1 had limited success in treating refractory EBV-associated lymphoma and post-transplant lymphoproliferative disorder, KSHV-associated Kaposi's sarcoma in AIDS patients, and HTLV-1-associated acute, chronic, and smoldering subtypes of adult T-cell lymphoma, respectively. Therapeutic HPV vaccine and RNA interference-based therapies for treating HPV-associated infection or cervical cancers also showed some encouraging results. Taken together, antiviral therapies have yielded promising results in cancer prevention and treatment. More large-scale studies in a real-world setting are necessary to confirm the efficacy of antiviral therapy. Further investigation for more effective and convenient antiviral regimens warrants more attention.

Pegylated interferon-α inhibits the proliferation of hepatocellular carcinoma cells by downregulating miR-155

INTRODUCTION AND AIMS

Interferon-α (IFN) has shown potential benefits in patients with hepatocellular carcinoma (HCC), and these effects may be mediated by inhibiting cancer cell proliferation. However, the detailed mechanisms underlying the anti-proliferative effects of IFN remain obscure. In this study, we evaluate the role of the novel oncogenic microRNA (miRNA) miR-155 in the anti-proliferative effects of pegylated interferon-α (PEG-IFN) on HCC cells.

METHODS

The effects of PEG-IFN on HepG2 cell proliferation, migration and invasion were determined using the MTT assay, flow cytometry analysis and the Transwell assay, respectively. Reverse transcription quantitative polymerase chain reaction was used to analyze miR-155 expression. The levels of proteins involved in Wnt/β-catenin signal transduction were determined by western blot analysis and immunofluorescence staining. Mimics of miR-155 were transfected into HepG2 cells to assess the role of miR-155 in the PEG-IFN-induced anti-proliferative effect.

RESULTS

PEG-IFN significantly inhibited the proliferation, migration and invasion of HepG2 cells in a dose-dependent manner by inhibiting cell cycle progression. In parallel with reduced cell proliferation, migration and invasion, miR-155 was efficiently downregulated by PEG-IFN in a dose-dependent manner. Moreover, the transfection of miR-155 decreased the inhibitory effect of PEG-IFN on HepG2cell proliferation, migration and invasion, as well as the downregulation of proteins in the Wnt/β-catenin pathway.

CONCLUSIONS

The anti-proliferative effects of PEG-IFN on HCC are at least partially attributable to the downregulation of miR-155.

Serum metabolome profiles characterized by patients with hepatocellular carcinoma associated with hepatitis B and C

AIM: To clarify the characteristics of metabolite profiles in virus-related hepatocellular carcinoma (HCC) patients using serum metabolome analysis.

METHODS: The serum levels of low-molecular-weight metabolites in 68 patients with HCC were quantified using capillary electrophoresis chromatography and mass spectrometry. Thirty and 38 of the patients suffered from hepatitis B virus-related HCC (HCC-B) and hepatitis C virus-related HCC (HCC-C), respectively.

RESULTS: The main metabolites characteristic of HCC were those associated with glutathione metabolism, notably 13 γ-glutamyl peptides, which are by-products of glutathione induction. Two major profiles, i.e., concentration patterns, of metabolites were identified in HCC patients, and these were classified into two groups: an HCC-B group and an HCC-C group including some of the HCC-B cases. The receiver operating characteristic curve for the multiple logistic regression model discriminating HCC-B from HCC-C incorporating the concentrations of glutamic acid, methionine and γ-glutamyl-glycine-glycine showed a highly significant area under the curve value of 0.94 (95%CI: 0.89-1.0, P < 0.0001).

CONCLUSION: The serum levels of γ-glutamyl peptides, as well as their concentration patterns, contribute to the development of potential biomarkers for virus-related HCC. The difference in metabolite profiles between HCC-B and HCC-C may reflect the respective metabolic reactions that underlie the different pathogeneses of these two types of HCC.

A comprehensive long-term prognosis of chronic hepatitis C patients with antiviral therapy: a meta-analysis of studies from 2008 to 2014

CONTEXT

Attaining a sustained virological response with antiviral therapy is a sign of clinical cure for chronic hepatitis C patients. The aim of this meta-analysis was to evaluate the long-term efficiency and outcome of antiviral therapy in patients with hepatitis C who attained a sustained virological response.

EVIDENCE ACQUISITION

A literature search was performed on published articles between January 2008 and February 2014. Patients with Hepatitis C who received interferon with or without ribavirin therapy were enrolled. Relative risks were estimated using either fixed or random effect models.

RESULTS

Patients who attained sustained virological response had a less risk (85%) for all-cause mortality and about 63% reduced risk of hepatocellular carcinoma incidence than those who did not achieve sustained virological response. Based on deeply analysis, the stage of liver fibrosis was a risk factor at baseline for the incidence of hepatocellular carcinoma.

CONCLUSIONS

Sustained virological response can reduce all-cause mortality and the incidence of hepatocellular carcinoma of patients with hepatitis C. Advanced liver fibrosis is still a risk factor for the incidence of hepatocellular carcinoma, in spite of hepatitis C patients attained a sustained virological response.

Thrombocytopenia in pegylated interferon and ribavirin combination therapy for chronic hepatitis C

BACKGROUND

This study aimed to examine the therapeutic effect and prognostic indicators of pegylated interferon (PEG-IFN) and ribavirin (RBV) combination therapy in thrombocytopenic patients with chronic hepatitis C, hepatitis C virus (HCV)-related cirrhosis, and those who underwent splenectomy or partial splenic embolization (PSE).

METHODS

Of 326 patients with HCV-related chronic liver disease (252 with genotype 1b and 74 with genotype 2a/2b) treated with PEG-IFN/RBV, 90 were diagnosed with cirrhosis.

RESULTS

Regardless of the degree of thrombocytopenia, the administration rate was significantly higher in the splenectomy/PSE group compared to the cirrhosis group. However, in patients with genotype 1b, the sustained virological response (SVR) rate was significantly lower in the cirrhosis and the splenectomy/PSE groups compared to the chronic hepatitis group. No cirrhotic patients with platelets less than 80,000 achieved an SVR. Patients with genotype 2a/2b were more likely to achieve an SVR than genotype 1b. Prognostic factors for SVR in patients with genotype 1b included the absence of esophageal and gastric varices, high serum ALT, low AST/ALT ratio, and the major homo type of the IL28B gene. Splenectomy- or PSE-facilitated induction of IFN in patients with genotype 2a/2b was more likely to achieve an SVR by an IFN dose maintenance regimen. Patients with genotype 1b have a low SVR regardless of splenectomy/PSE. In particular, patients with a hetero/minor type of IL28B did not have an SVR.

CONCLUSIONS

Splenectomy/PSE for IFN therapy should be performed in patients expected to achieve a treatment response, considering their genotype and IL28B.

Anti-viral treatment and cancer control

Hepatitis B virus (HBV), hepatitis C virus (HCV), human papillomavirus (HPV), and Epstein-Barr virus (EBV) contribute to about 10-15 % global burden of human cancers. Conventional chemotherapy or molecular target therapies have been used to treat virus-associated cancers. However, a more proactive approach would be the use of antiviral treatment to suppress or eliminate viral infections to prevent the occurrence of cancer in the first place. Antiviral treatments against chronic HBV and HCV infections have achieved this goal, with significant reduction in the incidence of hepatocellular carcinoma in treated patients. Antiviral treatments for EBV, Kaposi's sarcoma-associated herpesvirus (KSHV), and human T-cell lymphotropic virus type 1 (HTLV-1) had limited success in treating refractory EBV-associated lymphoma and post-transplant lymphoproliferative disorder, KSHV-associated Kaposi's sarcoma in AIDS patients, and HTLV-1-associated acute, chronic, and smoldering subtypes of adult T-cell lymphoma, respectively. Therapeutic HPV vaccine and RNA-interference-based therapies for treating HPV-associated cervical cancers also showed some encouraging results. Taken together, antiviral therapies have yielded promising results in cancer prevention and treatment. More large-scale studies are necessary to confirm the efficacy of antiviral therapy. Further investigation for more effective and convenient antiviral regimens warrants more attention.

Dynamics of serum metabolites in patients with chronic hepatitis C receiving pegylated interferon plus ribavirin: a metabolomics analysis

OBJECTIVES

Serum samples from patients with chronic hepatitis C were subjected to metabolomics analysis to clarify the pretreatment characteristics of their metabolites and also changes in specific metabolites resulting from antiviral therapy with pegylated interferon plus ribavirin (PegIFN/RBV).

MATERIALS/METHODS

The serum levels of low-molecular-weight metabolites in the twenty patients before and 24weeks after completion of PegIFN/RBV therapy were analyzed using capillary electrophoresis and liquid chromatography-mass spectrometry.

RESULTS

Ten patients showed a non-virological response (NVR) and 10 achieved a sustained virological response (SVR) with eradication of viremia. The pretreatment levels of tryptophan were significantly higher in the patients of SVR than in those of NVR (p=0.010). The area under the curve (AUC) value of tryptophan calculated from the receiver operating characteristic (ROC) curve for discriminating SVR from NVR was 0.84 (95% confidential interval, 0.66-1.02, p=0.010). The ROC curve of multiple logistic regression model incorporating the pretreatment levels of tryptophan and γ-glutamate-arginine showed that the AUC value was highly significant (AUC=0.92, 95% confidential interval, 0.79-1.05, p=0.002). Twenty four weeks after completion of treatment, the levels of γ-glutamyl dipeptides, glutamic acid, 5-oxoproline, glucosamine and methionine sulfoxide were decreased, whereas those of 5-methoxy-3-indoleacetate, glutamine, kynurenine and lysine were increased significantly (p<0.05) in both the NVR and SVR patients.

CONCLUSIONS

The pretreatment serum levels of certain metabolites including tryptophan are associated with the response to PegIFN/RBV therapy. PegIFN/RBV therapy can ameliorate the oxidative stress responsible for glutathione metabolism.

Interferon for interferon nonresponding and relapsing patients with chronic hepatitis C

BACKGROUND

The widely-accepted treatment outcome for chronic hepatitis C is the sustained viral response (that is, no measurable viral RNA in blood six months after treatment). However, this surrogate outcome (as well as the previously employed biochemical and histologic ones) has never been validated. This situation exists because there are very few randomized clinical trials that have used clinical events (mortality or manifestations of decompensated cirrhosis) as outcomes, because those clinical events only occur after many years of infection. Patients in whom initial therapy fails to produce sustained viral responses do become potential candidates for retreatment; some of these individuals are not candidates for ribavirin or protease inhibitors and consideration could be given to retreatment with interferon alone.

OBJECTIVES

To assess the benefits and harms of interferon monotherapy retreatment in chronic hepatitis C patients and to validate the currently employed surrogate outcomes in this group of patients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until 16 August 2012.

SELECTION CRITERIA

Randomized trials comparing interferon versus placebo or no treatment in chronic hepatitis C nonresponders and relapsers to previous interferon.

DATA COLLECTION AND ANALYSIS

The primary outcomes were mortality (all-cause and hepatic), quality of life, and adverse events. Secondary outcomes were liver-related morbidity, sustained viral responses, biochemical responses, histologic improvements, and costs. We used both fixed-effect and random-effects model meta-analyses, reporting only the former if no difference existed.

MAIN RESULTS

Seven trials were identified. Two of them were at low risk of bias (the HALT-C and EPIC3 trials) and included 1676 patients. Both of these trials addressed the role of long-term low-dose pegylated interferon therapy in patients with severe fibrosis (demonstrated on liver biopsy) and were designed to assess the clinical outcomes. The remaining five trials included 300 patients and were at high risk of bias. Based on all trials reporting the outcomes, no significant difference was observed in either all-cause mortality (78/843 (9.3%) versus 62/867 (7.2%); risk ratio (RR) 1.30, 95% confidence interval (CI) 0.95 to 1.79; 3 trials) or hepatic mortality (41/532 (7.7%) versus 40/552 (7.2%); RR 1.07, 95% CI 0.70 to 1.63; 2 trials); however, when only the two trials at low risk of bias were combined, all-cause mortality was significantly higher in the recipients of the pegylated interferon (78/828 (9.4%) versus 57/848 (6.7%); RR 1.41, 95% CI 1.02 to 1.96) although trial sequential analysis could not exclude the possibility of random error. There was less variceal bleeding in the recipients of the interferon (4/843 (0.5%) versus 18/867 (2.1%); RR 0.24, 95% CI 0.09 to 0.67; 3 trials), although again trial sequential analysis could not exclude the presence of a type I error and the effect could not be confirmed in a random-effects model meta-analysis. No significant differences were seen with regard to the development of ascites, encephalopathy, hepatocellular carcinoma, or the need for liver transplantation. One trial reported quality of life data; the pain score was significantly worse in the recipients of the pegylated interferon. Adverse effects tended to be more common in the interferon recipients; the ones that were significantly more common included hematologic complications, infections, flu-like symptoms, and rash. The recipients of interferon had significantly more sustained viral responses (20/557 (3.6%) versus 1/579 (0.2%); RR 15.38, 95% CI 2.93 to 80.71; 4 trials) and a type I error was excluded by trial sequential analysis. The METAVIR activity score also improved (36/55 (65%) versus 20/46 (43.5%); RR 1.49, 95% CI 1.02 to 2.18; 2 trials). No significant differences were seen with regard to histologic fibrosis assessments.

AUTHORS' CONCLUSIONS

The clinical data were limited to patients with histologic evidence of severe fibrosis who were retreated with pegylated interferon. In this scenario, retreatment with interferon did not appear to provide significant clinical benefit and, when only the trials at low risk of bias were considered, retreatment for several years may even have increased all-cause mortality. Such treatment also produced adverse events. On the other hand, the treatment did result in improvement in some surrogate outcomes, namely sustained viral responses and histologic evidence of inflammation. Interferon monotherapy retreatment cannot be recommended for these patients. No clinical data are available for patients with less severe fibrosis. The sustained viral response cannot be used as a surrogate marker for hepatitis C treatment in this clinical setting with low sustained viral response rates and needs to be validated in others in which higher sustained viral response rates are reported.

Inhibition of HCV 5'-NTR and core expression by a small hairpin RNA delivered by a histone gene carrier, HPhA

siRNA (small interfering RNA) interference represents an exciting new technology that could have therapeutic applications for the treatment of viral infections. However, a major challenge in the use of siRNA as a therapeutic agent is the development of a suitable delivery system. We demonstrated that a new non-viral transgene carrier, recombinant archaeal histone from the hyperthermophile Pyrococcus horikoshii OT3 (HPhA), can transfect short hairpin RNA (shRNA) expressing plasmids into HL-7702 cells to inhibit the expression of HCV 5'NTR and Core protein and mRNA. Plasmids Psilencirle transfected by HPhA inhibited the expression of HCV 5'-NTR and Core protein and mRNA in HL-7702 cells. The transfection efficiency of HPhA in HL-7702 cells was not affected by 10% fetal calf serum (FCS). HPhA exhibited effects of transfection without apparent toxicity, and with high affinity for DNA. This suggests that HPhA may be useful for RNAi-based gene therapy in vivo.

Prognostic significance of Cdx2 immunohistochemical expression in gastric cancer: a meta-analysis of published literatures

Cdx2 is a homeobox domain-containing transcription factor that is important in the development and differentiation of the intestinal cells, and served as a potential biomarker of tumor progression in early intestinal-type gastric cancer. However, its prognostic value and significance in gastric cancer remain controversial. A meta-analysis based on published studies was performed to obtain an accurate evaluation of the association between the presence of Cdx2-positive in clinical samples and clinical outcome. A total of 13 eligible retrospective cohort studies with 1513 patients were included. Cdx2-positive cases were significantly associated with higher male-to-female ratio (RR=1.27, 95% CI: 1.17-1.38, P<0.00001 fixed-effect), lower (I+II) clinical stage (RR=1.63, 95% CI: 1.42-1.87, P<0.00001 fixed-effect), better histologic differentiation (RR=1.54, 95% CI: 1.34-1.76, P<0.00001 fixed-effect), and lower rate of vascular invasion (RR=1.23, 95% CI: 1.08-1.41, P=0.002 fixed-effect) and lymph node metastasis (RR=1.52, 95% CI: 1.33-1.73, P<0.00001 fixed-effect), as well as higher 5-year survival rate (HR=2.22, 95% CI: 1.78-2.75, P<0.00001 fixed-effect). However, the presence of Cdx2 was not associated with tumor size. In summary, Cdx2 is a prognostic factor in gastric cancer, which acts as a marker of good outcome in patients with gastric cancer. Further clinical studies are needed to confirm the role of Cdx2 in clinical practice.