Combination Of IFN-alpha Research Articles

Abstract B13: New drug repositioning of low-dose pegylated IFN-alpha in combination with BH3 interacting domain death agonist gene and radiation therapy as a cancer treatment regimen

Abstract Purpose: Chemotherapy and radiation therapy (RT) are frequently selected for cancer treatment regimens, however they have limitations. Further regimens should be considered to overcome difficulties in cancer treatments. We have reported that interferon (IFN)-alpha induces in vitro cell death mediated by BH3-interacting domain death agonist (BID). However, low-dose pegyrated (PEG)-IFN-alpha, which suggests the possibilities of better adherence and fewer side effects, is clinically approved for treatment of hepatitis C, but not for that of any tumors. RT may also induce cell death. Here we assessed in vivo antitumor effects of pIRES-hBID (BID) transfection followed by low-dose PEG-IFN-alpha and RT (BID+IFN+RT). Experimental Procedures: A549 human lung carcinoma cells are resistant to both IFN-alpha and RT. In the present study, BID and low-dose PEG-IFN-alpha were administered into nude mice bearing subcutaneous A549 xenografts. The mice were then irradiated with 3 Gy gamma ray. These treatments were performed once a week for 4 weeks. Results: No body weight-loss was observed following any treatments. Immunohistochemistry demonstrated significantly less intranuclear localization of BID protein induced by BID alone and BID+IFN compared to mock alone and BID alone, respectively. These results suggest that each of BID and low-dose PEG-IFN-alpha affected BID translocation. Assessment of tumor volume indicated synergistic effects of growth inhibition induced by BID+IFN+RT. Electron microscopic examination of tumors on Day 56 demonstrated not only fragmented plasma membranes and nuclei but also cytoplasmic vesicles with degraded contents induced by BID+IFN+RT, indicating that low-dose PEG-IFN-alpha and RT following BID may induce both apoptotic and non-apoptotic cell death including autophagy and/or necrosis. Conclusions: Even low-dose PEG-IFN-alpha likely had antitumor effects when combined with BID and RT, suggesting the possibility of new drug repositioning of PEG-IFN-alpha. Consequently, BID+IFN+RT may be a promising regimen for treating tumors that are resistant to both IFN-alpha and RT. Citation Format: Takaya Tsuno, Shohei Kanno, Iwata Ryoichi, Noboru Tanigawa, Tetsuya Ueba. New drug repositioning of low-dose pegylated IFN-alpha in combination with BH3 interacting domain death agonist gene and radiation therapy as a cancer treatment regimen [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2017 Oct 1-4; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2018;6(9 Suppl):Abstract nr B13.

Activation of cAMP–protein kinase A abrogates STAT5-mediated inhibition of glucocorticoid receptor signaling by interferon-alpha

IFN-alpha has been found to inhibit glucocorticoid receptor (GR) function by activating janus kinase-signal transducer and activator of transcription (JAK-STAT) inflammatory signaling pathways. In contrast, through stimulation of protein kinase A (PKA), cAMP has been shown to enhance GR function and can inhibit inflammatory signaling. We therefore examined whether increased cAMP-PKA pathway activation could reverse IFN-alpha-induced inhibition of GR function and whether decreased cAMP-PKA activity might exacerbate IFN-alpha effects on the GR. Activation of cAMP by forskolin (10 μM) reversed the inhibitory effects of mIFN-alpha (1000 U/ml) on dexamethasone (DEX)-induced MMTV-luciferase activity in hippocampal HT22 cells. Forskolin treatment also blocked both IFN-alpha-induced activation of phosphorylated STAT5 (pSTAT5) and inhibitory protein-protein interactions between pSTAT5 and GR in the nucleus of HT22 cells treated with IFN-alpha and DEX. These effects of forskolin were reversed by co-administration of the PKA inhibitor, H89. Conversely, the combination of IFN-alpha and treatment with either H89 or siRNA directed against the alpha and beta catalytic subunit isoforms of PKA led to an additive inhibitory effect on DEX-induced GR activity in HT22 cells. Taken together, these findings suggest that inhibition of GR signaling by mIFN-alpha and STAT5 can be reversed by activation of cAMP-PKA pathways, whereas decreased PKA activity increases the inhibitory effect of IFN-alpha on GR function. Given decreased PKA activity found in patients with major depression, these data suggest that depressed patients may be vulnerable to cytokine effects on GR, and cAMP-PKA agonists may serve to reverse glucocorticoid resistance in patients with depression and increased inflammation.

Inhibitory effects on HAV IRES-mediated translation and replication by a combination of amantadine and interferon-alpha

Hepatitis A virus (HAV) causes acute hepatitis and sometimes leads to fulminant hepatitis. Amantadine is a tricyclic symmetric amine that inhibits the replication of many DNA and RNA viruses. Amantadine was reported to suppress HAV replication, and the efficacy of amantadine was exhibited in its inhibition of the internal ribosomal entry site (IRES) activities of HAV. Interferon (IFN) also has an antiviral effect through the induction of IFN stimulated genes (ISG) and the degradation of viral RNA. To explore the mechanism of the suppression of HAV replication, we examined the effects of the combination of amantadine and IFN-alpha on HAV IRES-mediated translation, HAV replicon replication in human hepatoma cell lines, and HAV KRM003 genotype IIIB strain replication in African green monkey kidney cell GL37. IFN-alpha seems to have no additive effect on HAV IRES-mediated translation inhibition by amantadine. However, suppressions of HAV replicon and HAV replication were stronger with the combination than with amantadine alone. In conclusion, amantadine, in combination of IFN-alpha, might have a beneficial effect in some patients with acute hepatitis A.

Interferon-α Produces Significant Decreases in HIV Load

A randomized, controlled clinical trial was started in the pre-HAART era to compare the efficacy of zidovudine (AZT) and interferon-alpha (IFN-alpha) either alone or in combination to reduce HIV viremia, maintain CD4(+) cell count, and decrease time to AIDS progression and death. The purpose of the current study was to compare the effects of AZT and IFN on HIV load using modern technology. One hundred and eighty patients with CD4(+) counts above 500 cells/mm(3) were randomized to receive AZT alone, IFN-alpha alone, or AZT and IFN-alpha in combination. CD4(+) cell count and HIV load at baseline and at the last follow-up visit were compared, and time to AIDS or death was calculated by treatment group. At a mean follow-up of 45 weeks, the mean change in log HIV RNA was -0.06 for the AZT alone group, -0.47 for the AZT plus IFN-alpha group (P = 0.01 versus AZT group), and -0.35 for the IFN-alpha alone group (P = 0.02 versus AZT group). There was no significant difference among groups in change in total CD4(+) count or in time to AIDS or death. Since treatment with IFN-alpha produces significant decreases in HIV load, additional studies of IFN-alpha as part of a combination regimen are warranted.

ChemInform Abstract: The Role of Interferon-Alpha in the Treatment of Myeloproliferative Disorders

The interferons are cytokines with a wide array of biological properties. In hematological malignancies the most used IFN class is -alpha; it has been used for thirty years but the mode of action is still not absolutely clear. Nevertheless, the benefits of IFN-alpha for the treatment of CMD have been described in particular for CML and less for PV, ET and MMM. IFN-alpha is presently considered the golden standard of therapy for CML patients not eligible for SCT; the antileukemic effect has been well documented by hematological and cytogenetic response. The survival advantage for IFN treated patients is remarkable in comparison with patients treated with conventional chemotherapy. Recently, the combination IFN-alpha plus Ara-C has demonstrated to increase the rate of major cytogenetic response and to prolong survival. To date, there is not a generally accepted treatment for ET, PV and MMM, which can reduce the risk of thromboembolism and/or hemorragic events. In several subsets of ET and PV patients, IFN-alpha can be considered as first line therapy. IFN-alpha is usually associated with the development of early and later side effects, that reduce the enthusiasm for its use. In the future PEG-IFN-alpha would improve the quality of life of IFN-treated CMD patients.

Hydroxyurea as an inhibitor of hepatitis C virus RNA replication

Hepatitis C virus (HCV) is the main causative agent of chronic liver disease, which may develop into liver cirrhosis and hepatocellular carcinoma. By using a recently developed reporter assay system in which genome-length HCV RNA replicates efficiently, we found that hydroxyurea (HU), a DNA synthesis inhibitor, inhibited HCV RNA replication. Moreover, we demonstrated that the anti-HCV activity of the combination of IFN-alpha and HU was higher than that of IFN-alpha alone. These results suggest that HU may be an effective anti-HCV reagent that can be used not only singly but also in combination with IFN-alpha to treat chronic hepatitis C.

Synergistic potentiation of interferon activity with maitake mushroom d‐fraction on bladder cancer cells

To examine whether the combination of interferon (IFN)-alpha and maitake mushroom D-fraction (PDF), a bioactive mushroom extract, might potentiate the anticancer activity of IFN-alpha in bladder cancer T24 cells in vitro. Effects of recombinant IFN-alpha(2b) (0-50 000 IU/mL), PDF (0-700 microg/mL), or their combinations were assessed on T24 cell growth at 72 h. Cell cycle analysis and assays for double-stranded DNA-dependent protein kinase (DNA-PK) were performed to explore possible antiproliferative mechanism of these agents. IFN-alpha(2b) was able to induce a significant ( approximately 50%) growth reduction at 20 000 IU/mL, which further declined to approximately 66% at 50 000 IU/mL. PDF had no effects up to 200 microg/mL, but there was an approximately 20% and approximately 53% growth reduction at 400 and 700 microg/mL, respectively. When the varying concentrations of IFN-alpha(2b) and PDF were combined, 10 000 IU/mL of IFN-alpha(2b) combined with 200 microg/mL of PDF resulted in an approximately 75% growth reduction. This was accompanied by a G(1) cell cycle arrest, shown by cell cycle analysis. Concurrently, DNA-PK activity in IFN-alpha(2b)/PDF-treated cells was almost three-fold higher than controls. The combination of IFN-alpha(2b) (10 000 IU/mL) and PDF (200 microg/mL) reduced growth by approximately 75% in T24 cells. This appears to be due to a synergistic potentiation of these two agents, inducing a G(1) arrest with DNA-PK activation. Therefore, the IFN-alpha(2b)/PDF combination could trigger DNA-PK activation that may act on the cell cycle to cease cancer cell growth.

Calcineurin inhibitor tacrolimus does not interfere with the suppression of hepatitis C virus infection by interferon-α

Immunosuppression considerably affects hepatitis C virus (HCV) recurrence and the outcome of antiviral treatment after liver transplantation. Recent findings have suggested that the calcineurin inhibitor tacrolimus (Tac), unlike cyclosporine A (CsA), interferes with the antiviral activity of interferon-alpha (IFN-alpha) in vitro. The aim of this study was to more extensively investigate the effects of calcineurin inhibitors on IFN-alpha signaling and antiviral activity in subgenomic and infectious HCV models. Treatment with Tac and CsA did not affect Huh7 cell proliferation at doses of 10 to 500 ng/mL; however, it completely inhibited T cell proliferation. In contrast to previous reports, Tac had no effect on IFN-alpha-stimulated reporter gene expression, even at the dose of 5 microg/mL. Furthermore, in Huh7 subgenomic HCV replicon cells, treatment with Tac had no significant effect on the suppression of viral replication by IFN-alpha. In the infectious HCV model, treatment with IFN-alpha effectively inhibited both viral RNA replication and de novo production of virus particles, and neither was attenuated at any concentration of Tac. CsA had no significant effect on IFN-alpha-stimulated reporter gene expression; however, as shown previously, a combination of CsA (at 500 ng/mL and higher) and IFN-alpha resulted in enhanced inhibition of viral replication in both the subgenomic and infectious HCV models. In conclusion, our study shows no evidence that Tac or CsA interferes with IFN-alpha-mediated inhibition of HCV replication and virion production in vitro. Therefore, no further mechanistic arguments have been found to break the clinical controversy about the choice of calcineurin inhibitors during posttransplantation antiviral therapy.

The potential use of Toll-like receptor agonists to restore the dysfunctional immunity induced by hepatitis C virus

Hepatitis C virus (HCV) infection is a major public health concern with approximately 3% of the world's population is infected, posing social, economical and health burden. Less than 20% of the infected individuals clear the virus during the acute infection, while the rest develop chronic infection. The treatment of choice for HCV infection is pegylated interferon-alpha (IFN-alpha) in combination with ribavarin. Despite the cost and side effects of this treatment regimen, many patients fail this therapy and develop persistent HCV infection, leading to cirrhosis and hepatocellular carcinoma. Although the mechanisms underlying the failure to resolve HCV infection are poorly understood, the incapability of patients to develop effective anti-HCV immunity is a potential cause. We hypothesize that the dysfunctional anti-HCV immunity is due to the emergence of immunosuppressive cells coinciding with a decrease in the stimulatory dendritic cells (DCs) and natural killer (NK) cells. We further hypothesize that applying agents that can correct the imbalance between the immunosuppressive cells and stimulatory cells can results in resolution of chronic HCV. In this review article, we will discuss potential approaches, focusing on the use of Toll-like receptor agonists, to block the suppressive effects of the regulatory cells and restore the stimulatory effects of DCs and NK cells.

Xanthohumol enhances antiviral effect of interferon α-2b against bovine viral diarrhea virus, a surrogate of hepatitis C virus

Xanthohumol (XN) is a natural compound with multifunctional potentials, including antiviral activity. In this study, the antiviral activity of addition of XN to interferon (IFN)-alpha was examined and compared with each compound alone using bovine viral diarrhea virus (BVDV), a surrogate model of hepatitis C virus (HCV). BVDV E2 protein and the viral RNA level were determined by immunofluorescence and quantitative real-time RT-PCR, respectively. The addition of XN to IFN-alpha significantly improved CPEs induced by the virus and inhibited BVDV E2 protein and viral RNA levels. The interaction between XN and IFN-alpha was significant (P<0.001). XN at 3.13 microg/ml in combination with IFN-alpha at 50 IU/ml showed greater inhibitory effect on the viral RNA level than each compound used alone at 6.25 microg/ml and 100 IU/ml, respectively, indicating synergistic effect on BVDV replication in this combination. The inhibitory activity in all the tested combinations of XN and IFN-alpha was stronger than that of each compound used alone at the corresponding concentration. These results suggest that XN in combination with IFN-alpha exhibited a greater in vitro antiviral effect compared with each compound used alone. Further studies are deserved to investigate the anti-HCV activity of XN and the potential of XN in formulating novel anti-HCV regimen.

Multicenter Phase II Trial of Combination Therapy with Meloxicam, a COX-2 Inhibitor, and Natural Interferon- for Metastatic Renal Cell Carcinoma

We conducted a Phase II trial to investigate the efficacy of combined therapy with meloxicam, a cyclooxygenase-2 inhibitor and natural interferon (IFN)-alpha in renal cell carcinoma patients with distant metastasis. The subjects of this study were patients with untreated renal cell carcinoma who were diagnosed from the results of imaging or pathological studies and who had measurable lesions according to the Response Evaluation Criteria in Solid Tumors (RECIST). Patients could be enrolled in the study irrespective of whether nephrectomy had been performed. Treatment involved the subcutaneous injection of natural IFN-alpha at 3 x 10(6) or 5 x 10(6) U three times weekly plus oral administration of meloxicam at 10 mg once daily. A total of 43 patients were enrolled in the present study, included 11 patients without nephrectomy, 23 patients with a high C-reactive protein (CRP) level and 23 patients with extrapulmonary metastasis. Four patients of complete response and 12 patients of partial response were confirmed, given an overall response rate of 37.2% (95% confidence interval, 23.0-53.3%). Stable disease for 6 months or longer was also obtained in 14 patients. The median time to progression was 14 months. Adverse events (AEs) observed were mainly flu-like symptoms due to cytokine. Although the Grade 3 or 4 AEs were fatigue, hepatic dysfunction, arthritis and gastric ulcer, all but one (gastric ulcer) were immediately improved by discontinuation of this combined therapy. The combination of meloxicam and natural IFN-alpha is considered to be an active regimen with tolerable toxicities as a first-line treatment of metastatic renal cell carcinoma.

The antitumor and immunoadjuvant effects of IFN-alpha in combination with recombinant poxvirus vaccines.

IFN-alpha is a pleiotropic cytokine possessing immunomodulatory properties that may improve the efficacy of therapeutic cancer vaccines. The aim of this study was to evaluate the effectiveness and compatibility of combining recombinant IFN-alpha with poxvirus vaccines targeting the human carcinoembryonic antigen (CEA) in murine models of colorectal and pancreatic adenocarcinomas, where CEA is a self-antigen. The phenotypic and functional effects of IFN-alpha were evaluated in the draining inguinal lymph nodes of tumor-free mice. We studied the effect of the site of IFN-alpha administration (local versus distal) on antigen-specific immune responses to poxvirus vaccination. Mechanistic studies were conducted to assess the efficacy of IFN-alpha and CEA-directed poxvirus vaccines in tumor-bearing CEA transgenic mice. We identified a dose and schedule of IFN-alpha that induced a locoregional expansion of the draining inguinal lymph nodes and improved cellular cytotoxicity (natural killer and CD8(+)) and antigen presentation. Suppression of the vaccinia virus was avoided by administering IFN-alpha distal to the site of vaccination. The combination of IFN-alpha and vaccine inhibited tumor growth, improved survival, and elicited CEA-specific CTL responses in mice with CEA(+) adenocarcinomas. In mice with pancreatic tumors, IFN-alpha slowed tumor growth, induced CTL activity, and increased CD8(+) tumor-infiltrating lymphocytes. These data suggest that IFN-alpha can be used as a biological response modifier with antigen-directed poxvirus vaccines to yield significant therapeutic antitumor immune responses. This study provides the rationale and mechanistic insights to support a clinical trial of this immunotherapeutic strategy in patients with CEA-expressing carcinomas.

Präklinische Studien zum Einfluss des Tyrosinkinaseinhibitors AEE788 auf die Malignität des Nierenzellkarzinoms

Conventional therapeutic approaches to treat advanced renal cell carcinoma (RCC) are of limited benefit. Receptor tyrosine kinase inhibitors (RTKI) may open up novel treatment options. In the present study, the effects of the RTKI AEE788 on the growth and adhesion capacity of RCC cell lines were evaluated in vitro. RCC cells were treated with AEE788, and alterations of tumor growth and tumor cell interaction with vascular endothelium or extracellular matrix proteins were analyzed. Furthermore, the addition of interferon alpha (IFNalpha) was investigated to see whether it may enhance the anti-tumoral potential of AEE788. AEE788 significantly blocked RCC cell growth and adhesion. Analysis of alpha- and beta-integrins revealed distinct alterations of the receptor expression profile and downregulation of integrin-dependent signaling. Growth-blocking effects were further enhanced when the AEE788-IFNalpha combination protocol was applied. In addition, downregulation of integrin-dependent signaling was more intense in the presence of a combination of AEE788 and IFNalpha than with AEE788 monotherapy. AEE788 exerts significant anti-tumoral properties, particularly when combined with IFNalpha. AEE788 may therefore be an encouraging compound to treat advanced RCC.

Griseofulvin, an oral antifungal agent, suppresses hepatitis C virus replication in vitro

Hepatitis C virus (HCV), which infects an estimated 170 million people worldwide, is a major cause of chronic liver disease. The current standard therapy for chronic hepatitis C is based on pegylated interferon (IFN)alpha in combination with ribavirin. However, the success rate remains at approximately 50%. Therefore, alternative agents are needed for the treatment of HCV infection. Using an HCV-1b subgenomic replicon cell culture system (Huh7/Rep-Feo), we found that griseofulvin, an oral antifungal agent, suppressed HCV-RNA replication and protein expression in a dose-dependent manner. We also found that griseofulvin suppressed the replication of infectious HCV JFH-1. A combination of IFNalpha and griseofulvin exhibited a synergistic inhibitory effect in Huh7/Rep-Feo cells. We found that griseofulvin blocked the cell cycle at the G(2)/M phase in the HCV subgenomic replicon cells, but did not inhibit HCV internal ribosome entry site-dependent translation. Our results suggest that griseofulvin may represent a new approach to the development of a novel therapy for HCV infection.

Phase I analysis of BCNU-impregnated biodegradable polymer wafers followed by systemic interferon alfa-2b in adults with recurrent glioblastoma multiforme

Carmustine (BCNU)-impregnated biodegradable polymer wafers have been shown to prolong survival in patients with recurrent malignant glioma. Interferon alfa-2b (IFNalpha(2b)) has demonstrated antitumor activity against a number of cancers, but its use in glioma has been limited. The use of these agents in combination is appealing because the mode of antitumor activity likely differs. This is a report of a phase I dose-finding study for IFNalpha(2b) in combination with surgery and BCNU wafers in patients with recurrent glioblastoma. Patients with progressive malignant glioma that was confirmed intraoperatively to be glioblastoma were treated with surgical resection and implantation of 8 BCNU wafers. A week later, IFNalpha(2b) was initiated three times a week at a dose of 3 MU/m(2), which was escalated in increments of 3 MU/m(2). The treatment cycle encompassed 8 weeks. Toxicity was monitored by clinical and laboratory testing. Correlative studies of methylguanine methyltransferase (MGMT) expression and gene expression array analysis were carried out. Ten patients were enrolled, and 9 patients had evaluable data. Dose-limiting toxicity in the form of fatigue occurred at 9 MU/m(2). Two complete imaging responses were observed at the 3 MU/m(2) dose. MGMT expression and gene expression arrays did not correlate with toxicity or response. Multimodal therapy with surgery, BCNU wafers, and IFNalpha(2b) appears to be a feasible and safe treatment strategy. The maximum tolerated dose of IFNalpha(2b) was determined to be 6 MU/m(2). Analysis of MGMT expression and gene expression was feasible.

A Support Vector Machine Approach to Assess Drug Efficacy of Interferon-α and Ribavirin Combination Therapy

Interferon-alpha (IFNalpha) in combination with ribavirin can be used for the treatment of patients with chronic hepatitis C. This therapeutic approach achieves an overall sustained response rate of approximately 40%, but treatment takes 6-12 months and patients often experience significant adverse reactions. We aim to develop a tool to distinguish potential responders from nonresponders prior to initiation of IFNalpha-ribavirin treatment. Using single nucleotide polymorphisms (SNPs) and viral genotype, we applied the support vector machine (SVM) algorithm to build a tool to predict responsiveness to IFNalpha-ribavirin combination therapy. Furthermore, we utilized the SVM algorithm with the recursive feature elimination method to identify a subset of factors that are significantly more influential than the others. The SVM model is a promising method for inferring responsiveness to IFNalpha dealing with the complex nonlinear relationship between factors (such as SNPs and viral genotype) and successful therapy. In this study, we demonstrate that our tool may allow patients and doctors to make more informed decisions by analyzing host SNP and viral genotype information.

Interferon-α in Combination With Chemotherapy has Potent Antiangiogenic Properties in an Orthotopic Mouse Model for Pancreatic Adenocarcinoma

There are clinical data showing encouraging results for combining chemoradiotherapy with interferon (IFN)-alpha (CapRI scheme) for the treatment of pancreatic carcinoma. Here, it was tried to evaluate the antiangiogenic effect of IFN-alpha in combination with chemotherapy. Mice were inoculated with syngeneic pancreatic carcinoma cells in the pancreas. After 5 days, the animals were treated with 5-fluorouracil (5-FU)+/-IFN-alpha. Tumor growth, vascular endothelial growth factor (VEGF) serum levels and VEGF-R expression, real-time reverse transcription-polymerase chain reaction of mRNA coding for RGS-5, an angiogenic pericyte marker at sites of physiologic and pathologic angiogenesis and impact of IFN-alpha treatment on vessel density by CD31 stain and intravital microscopy were analyzed. The addition of IFN-alpha to 5-FU-treatment decreased tumor volume, reduced serum level of VEGF, and down-regulated the expression of VEGF-receptor significantly. Furthermore, the combination therapy revealed a decrease in vessel density and a down-regulation of RGS-5, which is a protein involved in angiogenic tumor vasculature. IFN-alpha significantly improves the outcome of 5-FU-therapy in treating pancreatic carcinoma. This is at least partly mediated by IFN-alpha antiangiogenic properties, which acts along with 5-FU on the VEGF system, vessel density, and RGS-5 expression in pericytes.

Comparison of therapeutic results between combination therapy of peginterferon alpha-2a plus ribavirin and interferon alpha-2b plus ribavirin according to treatment duration in patients with chronic hepatitis C

This study compared the efficacy and safety of combined peginterferon alfa (PEG-IFN) and ribavirin with that of combined interferon alpha (IFN-alpha) and ribavirin, according to the treatment duration in Korean patients with chronic hepatitis C. Medical records of 86 patients treated with PEG-IFN and ribavirin (mean age, 50.7 years; males/females, 57/29; genotypes 1/2, 59/27) and 134 patients treated with IFN-alpha and ribavirin (mean age, 50.9 years; males/females 74/60; genotypes 1/2, 79/55) were reviewed. Ribavirin was administered at doses of 600-1,200 mg and 600-800 mg in patients with genotypes 1 and 2, respectively. Sustained virological responses (SVRs) were evident in 68.4% and 41.7% of genotype 1 patients treated for 48 weeks in the PEG-IFN and IFN-alpha groups, respectively (P=0.021), and in 94.1% and 64.9% of genotype 2 patients treated for 24 weeks (P=0.026). Some genotype 1 patients treated for 24 weeks in the PEG-IFN group, who all exhibited negative HCV PCR results at week 12, showed an SVR of 87.5% (7/8). The rate of SVRs in Korean patients with chronic hepatitis C was higher for combined PEG-IFN and ribavirin than for combined IFN-alpha and ribavirin. Further study is needed to clarify the outcome of short-term therapy in patients with a rapid or early virological response.

Combination therapy of interferon-α and 5-fluorouracil inhibits tumor angiogenesis in human hepatocellular carcinoma cells by regulating vascular endothelial growth factor and angiopoietins

We recently reported that interferon-alpha (IFN-alpha) and 5-fluorouracil (5-FU) combination therapy in advanced hepatocellular carcinoma (HCC) achieved excellent clinical results. However, the mechanism underlying this combination therapy remains to be elucidated. In this study, we examined the anti-tumor effects of IFN-alpha and 5-FU combination therapy in vivo and aimed to reveal its anti-angiogenic effects by investigating the expression of vascular endothelial growth factor (VEGF) and angiopoietins (Ang-1 and Ang-2). Human HCC cells, HuH7, were subcutaneously injected in nude mice. Ten days later, groups of mice received treatment with IFN-alpha alone, 5-FU alone, or with a combination of IFN-alpha and 5-FU for four weeks. Immunohistochemical examinations of proliferating cell nuclear antigen (PCNA), cell differentiation antigen 34 (CD34), Ang-1, -2 and VEGF, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and quantification of VEGF, Ang-1 and-2 mRNA using real-time RT-PCR were performed. Results showed that IFN-alpha and 5-FU combination therapy significantly inhibited the growth of human HCC cells compared with the control group or single agent treatment. The combination therapy decreased PCNA-positive cells as well as microvessel density (MVD) and induced apoptosis of (TUNEL-positive cells) more than other treatment groups. Immunohistochemical analysis revealed that the combination therapy significantly decreased the expression of VEGF and Ang-2 and increased that of Ang-1. The ANG2/ANG1 mRNA expression ratio was significantly lower in the combination therapy group. In conclusion, our results suggested that IFN-alpha and 5-FU combination therapy has anti-proliferative and anti-angiogenic effects and can induce apoptosis in vivo. The synergistic and anti-angiogenic effects may in part be attributable to the regulation of Ang-1, -2 and VEGF.

Polymorphisms in the IFNAR1 gene in patients with chronic hepatitis C: outcome of combined IFN-alpha therapy.

Interferon-alpha (IFN-alpha) alone or in combination with ribavirin has been used for the last decade in the treatment of chronic hepatitis C, although the achievement of a sustained virological response (SVR) has not been very satisfactory. The treatment outcome depends on viral genotypes and host genetic polymorphisms in genes involved in the IFN-alpha signaling cascade. In this paper, we investigated the distribution of two variants of the IFNAR1 gene, G17470C and L168V, in two patient groups having received IFN-alpha alone or in combination with ribavirin. The analysis was performed using DNA sequencing of the relevant gene fragments. This study suggests that when combination therapy with high dose IFN-alpha and ribavirin is administered, HCV genotypes and age rather than the IFNAR1 polymorphisms are the predictors of a sustained response.