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Interferon Alpha (interferon + alpha)
Selected AbstractsAutoimmunity as a prognostic factor in melanoma patients treated with adjuvant low-dose interferon alphaINTERNATIONAL JOURNAL OF CANCER, Issue 11 2007Imke Satzger Abstract Interferon alpha is used for the adjuvant treatment of malignant melanoma at different dosages (high-, intermediate-, low-dose therapy). Only a minority of patients might benefit from this therapy, and markers to identify such patients are missing. A recent study suggested that melanoma patients developing autoantibodies or clinical manifestations of autoimmunity during adjuvant high-dose interferon alpha treatment had a significant survival benefit. We retrospectively reviewed 134 melanoma patients from our institution treated with adjuvant low-dose interferon alpha therapy and correlated the development of autoimmune diseases with prognosis. Interferon (IFN) therapy was routinely monitored by history, physical examination and laboratory tests before, after the first month and then after every 3 months of therapy. During a median follow up of 46.0 months (8.5,79.0 months) 28 patients (20.9%) suffered from recurrences and melanoma related deaths occurred in 16 patients (11.9%). In 20 patients (14.9%) autoimmune thyroiditis (AIT) was diagnosed during IFN therapy, one of these 20 patients developed rheumatoid arthritis later while continuing IFN therapy. Other autoimmune diseases were not observed. In 2 patients (one with AIT and one with arthritis) the autoimmune disease led to discontinuation of IFN therapy, in the other patients AIT remained subclinical or responded well to treatment while IFN therapy was continued. Kaplan,Meier analyses revealed a significant better recurrence free survival and a trend for a better overall survival for patients with AIT. Thus, autoimmunity triggered by low-dose IFN therapy appears to indicate an improved prognosis and should encourage continuation of IFN therapy. © 2007 Wiley-Liss, Inc. [source] Interferon-alpha therapy in idiopathic thrombocytopenic purpuraPEDIATRICS INTERNATIONAL, Issue 6 2001Bunyamin Dikici AbstractBackground: Acute idiopathic thrombocytopenic purpura (ITP) represents the most frequent hemorrhagic diathesis in childhood. Up to 30% of patients with ITP are regarded as refractory to standard therapy. The rare mortality from acute ITP in childhood is almost exclusively due to intracranial hemorrhage. This complication occurs in less than 1% of ITP patients. This study was designed to evaluate the effect of ,-interferon (IFN-,) in eight patients whom did not respond to conventional therapy. Method: In spite of conventional therapies, the patient whose platelet count could not be increased to 50`109/L were accepted as refractory ITP. Eight of these patients whose platelet count lower than 20`109/L were included in the prospective cohort study. Interferon alpha 2b 5 MU/m2 was administered subcutaneously three times a week, totalling 12 times in a month. According to the platelet count on the 28th day of therapy, we grouped the patients into three categories. After 60 days, the survey was re-evaluated according to the platelet count. Results: The mean age of children was 3.5±2.5 (ranged between 3.5 and 9) years. Six of them were boys and two were girls. There was no response in one patient, partial response in one, and good response in six patients on the 28th day of therapy. The maximum rise in platelet count was observed from 7 to 14 days after the initiation of interferon. The median platelet count which was 15±5`109/L before therapy, raised to 60±12`109/L after therapy. However, on the 60th day of therapy, there were only two patients who had a platelet count over 100`109/L. Conclusion: In our study, we did not observe the long-term benefit of IFN-, therapy in refractor ITP in childhood. However, in good responding patients, platelet levels were increased in a short time. Alpha-interferon may be alternative therapy for patients whom had a platelet count below 20`109/L and not responding to standard therapy, or for patients whom immunosuppressive therapy is contraindicated. [source] Sodium dodecyl sulfate-capillary gel electrophoresis of polyethylene glycolylated interferon alphaELECTROPHORESIS, Issue 3 2004Dong H. Na Abstract Sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE) using a hydrophilic replaceable polymer network matrix was applied to characterize the polyethylene glycol(PEG)ylated interferon alpha (PEG-IFN). The SDS-CGE method resulted in a clearer resolution in both the PEG-IFN species and the native IFN species. The distribution profile of PEGylation determined by SDS-CGE was consistent with that obtained by SDS-polyacrylamide gel electrophoresis (PAGE) with Coomassie blue or barium iodide staining. The result was also compared using matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. SDS-CGE was also useful for monitoring the PEGylation reaction to optimize the reaction conditions, such as reaction molar ratio. This study shows the potential of SDS-CGE as a new method for characterizing the PEGylated proteins with advantages of speed, minimal sample consumption and high resolution. [source] Hepatitis C treatment in "difficult-to-treat" psychiatric patients with pegylated interferon-alpha and ribavirin: Response and psychiatric side effects,HEPATOLOGY, Issue 4 2007Martin Schaefer We investigated and compared the results of treating the chronic hepatitis C (HCV) infection of different groups of psychiatric-risk patients and controls with pegylated interferon alpha (pegIFN-,) plus ribavirin. Seventy patients were prospectively screened for psychiatric disorders. Seventeen patients without psychiatric diseases or drug addiction (controls), 22 patients with psychiatric disorders, 18 patients who had received methadone substitution treatment and 13 patients who were former drug users were treated with pegIFN-, plus ribavirin. Sustained virological response (SVR), adherence, and psychiatric side effects (using the Montgomery-Asberg Depression Rating Scale and the Brief Psychiatric Rating Scale) in the groups were compared. An SVR was found in 58.6% of all patients: 58.8% of the controls, 50% of psychiatric patients, 72.2% of methadone patients, and 53.8% of former drug users. Methadone-substituted patients and former drug users had significantly higher dropout rates. Scores for neither depressive nor psychotic symptoms differed significantly between groups during treatment. However, the controls had lower pretreatment scores, followed by a significant higher increase to maximum scores. A stepwise logistic regression model showed that only genotype, not group (control, psychiatric, methadone, or former drug abuse), type of psychiatric diagnosis (affective disorder, personality disorder, or schizophrenic disorder), depression scores before and during treatment, change in depression score, antidepressive treatment, sex, or liver enzymes before treatment, was associated with SVR. Conclusion: In an interdisciplinary treatment setting psychiatric diseases and/or drug addiction did not negatively influence psychiatric tolerability of and antiviral response rate to HCV treatment with pegIFN-, and ribavirin. (HEPATOLOGY 2007.) [source] Interferon-inducible expression of APOBEC3 editing enzymes in human hepatocytes and inhibition of hepatitis B virus replication,HEPATOLOGY, Issue 6 2006Marianne Bonvin Hypermutations in hepatitis B virus (HBV) DNA by APOBEC3 cytidine deaminases have been detected in vitro and in vivo, and APOBEC3G (A3G) and APOBEC3F (A3F) have been shown to inhibit the replication of HBV in vitro, but the presumably low or even absent hepatic expression of these enzymes has raised the question as to their physiological impact on HBV replication. We show that normal human liver expresses the mRNAs of APOBEC3B (A3B), APOBEC3C (A3C), A3F, and A3G. In primary human hepatocytes, interferon alpha (IFN-,) stimulated the expression of these cytidine deaminases up to 14-fold, and the mRNAs of A3G, A3F, and A3B reached expression levels of 10%, 3%, and 3%, respectively, relative to GAPDH mRNA abundance. On transfection, the full-length protein A3BL inhibited HBV replication in vitro as efficiently as A3G or A3F, whereas the truncated splice variant A3BS and A3C had no effect. A3BL and A3BS were detected predominantly in the nucleus of uninfected cells; however, in HBV-expressing cells both proteins were found also in the cytoplasm and were associated with HBV viral particles, similarly to A3G and A3F. Moreover, A3G, A3F, and A3BL, but not A3BS, induced extensive G-to-A hypermutations in a fraction of the replicated HBV genomes. In conclusion, the editing enzymes A3BL, A3F, and most markedly A3G, which are expressed in liver and up-regulated by IFN-, in hepatocytes, are candidates to contribute to the noncytolytic clearance of HBV. (HEPATOLOGY 2006;43:1364,1374.) [source] Autoimmunity as a prognostic factor in melanoma patients treated with adjuvant low-dose interferon alphaINTERNATIONAL JOURNAL OF CANCER, Issue 11 2007Imke Satzger Abstract Interferon alpha is used for the adjuvant treatment of malignant melanoma at different dosages (high-, intermediate-, low-dose therapy). Only a minority of patients might benefit from this therapy, and markers to identify such patients are missing. A recent study suggested that melanoma patients developing autoantibodies or clinical manifestations of autoimmunity during adjuvant high-dose interferon alpha treatment had a significant survival benefit. We retrospectively reviewed 134 melanoma patients from our institution treated with adjuvant low-dose interferon alpha therapy and correlated the development of autoimmune diseases with prognosis. Interferon (IFN) therapy was routinely monitored by history, physical examination and laboratory tests before, after the first month and then after every 3 months of therapy. During a median follow up of 46.0 months (8.5,79.0 months) 28 patients (20.9%) suffered from recurrences and melanoma related deaths occurred in 16 patients (11.9%). In 20 patients (14.9%) autoimmune thyroiditis (AIT) was diagnosed during IFN therapy, one of these 20 patients developed rheumatoid arthritis later while continuing IFN therapy. Other autoimmune diseases were not observed. In 2 patients (one with AIT and one with arthritis) the autoimmune disease led to discontinuation of IFN therapy, in the other patients AIT remained subclinical or responded well to treatment while IFN therapy was continued. Kaplan,Meier analyses revealed a significant better recurrence free survival and a trend for a better overall survival for patients with AIT. Thus, autoimmunity triggered by low-dose IFN therapy appears to indicate an improved prognosis and should encourage continuation of IFN therapy. © 2007 Wiley-Liss, Inc. [source] Effects of interferon alpha therapy on the catalytic domains of the polymerase gene and basal core promoter, precore and core regions of hepatitis B virusJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2003ROBERT YUNG MING CHEN Aims: The aim of the present study was to examine the catalytic domains of the polymerase gene, the basal core promoter and the precore and core regions of the hepatitis B virus (HBV) genome for specific mutations. These may account for the response to interferon alpha (IFN-,) treatment, which may have prognostic value. Methods: Multiple serum samples were collected prospectively from 30 patients with chronic active hepatitis B who were treated with IFN-,. Patients were assigned to one of three groups: group A (n = 11) and group B (n = 10) individuals were hepatitis B e antigen (HBeAg)-positive prior to treatment. Group A patients underwent HBeAg seroconversion after treatment while group B patients did not. Group C (n = 9) patients were HBeAg-negative prior to treatment. The HBV DNA was extracted from the sera collected before, during and after treatment and the various genomic regions were amplified, sequenced and examined for mutations. Results: During IFN-, therapy, multiple changes were found in the catalytic domains of the HBV polymerase gene in all groups. The frequency of mutations and associated amino acid changes were highest in virus from group C patients and lowest in group A patients. The interdomain regions of the viral polymerase were the most affected. Multiple mutations were also found in the precore, core and core promoter regions. However, no specific mutations were associated with clinical response or outcome. Conclusions: During IFN-, treatment, multiple mutations occurred in the HBV genome, including the catalytic domains of the polymerase gene. Changes that did occur could not be correlated to the clinical response or treatment outcome. However, no mutations were found that have been linked to lamivudine escape, indicating that lamivudine therapy would be effective in IFN-, non-responder patients. [source] Pleural effusion associated with pegylated interferon alpha and ribavirin treatment for chronic hepatitis C,JOURNAL OF HOSPITAL MEDICINE, Issue 7 2009Amit Arora Abstract Lung toxicity related to interferon (IFN) alpha typically takes a form of interstitial pneumonitis, granulomatous inflammation, or organizing pneumonia. We report a case of a 52-year-old woman, who developed pneumonitis with exudative, lymphocytic-predominant pleural effusion following treatment with pegylated IFN alpha and ribavirin for hepatitis C. Her symptoms and lung findings resolved over 3 months of observation without corticosteroid therapy. Journal of Hospital Medicine 2009;4:E45,E46. © 2009 Society of Hospital Medicine. [source] Serum concentrations of ribavirin and pegylated interferon and viral responses in patients infected with HIV and HCVJOURNAL OF MEDICAL VIROLOGY, Issue 9 2008Florence Nicot Abstract The hepatitis C virus (HCV) infects a substantial proportion of patients infected with human immunodeficiency virus (HIV). Patients infected with both HCV and HIV respond poorly to anti-HCV treatment with pegylated interferon alpha and ribavirin. But few data are available on the influence of ribavirin and interferon concentrations on treatment outcome for these patients. This study investigated the relationship between the serum pegylated interferon and ribavirin concentrations 3 and 6 months after treatment initiation, and treatment outcome in 35 HCV-HIV coinfected patients. The pegylated interferon and ribavirin concentrations at months 3 and 6 were similar. The pegylated interferon concentrations at 3 months in responders and nonresponders were similar. However, responders tended to have higher ribavirin concentrations (2,322 ng/ml) than nonresponders (1,833 ng/ml; P,=,0.08). Responders infected with HCV genotype 1 or 4 had higher ribavirin concentrations (2,672 ng/ml) than did similarly infected nonresponders (1,758 ng/ml; P,=,0.04). ROC curve analysis showed that a ribavirin concentration of 2,300 ng/ml was the best threshold for predicting a nonresponse (ROC area,=,0.80,±,0.12). Thus ribavirin concentrations influence treatment outcome in HIV patients infected with HCV genotype 1 or 4. Monitoring ribavirin concentrations could help adapt ribavirin concentrations and improve the sustained virological response. J. Med. Virol. 80:1523,1529, 2008. © 2008 Wiley-Liss, Inc. [source] Practical aspects of management of recurrent aphthous stomatitisJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 8 2007A Altenburg Treatment of recurrent aphthous stomatitis (RAS) remains, to date, empirical and non-specific. The main goals of therapy are to minimize pain and functional disabilities as well as decrease inflammatory reactions and frequency of recurrences. Locally, symptomatically acting modalities are the standard treatment in simple cases of RAS. Examples include topical anaesthetics and analgesics, antiseptic and anti-phlogistic preparations, topical steroids as cream, paste or lotions, antacids like sucralfate, chemically stable tetracycline suspension, medicated toothpaste containing the enzymes amyloglucosidase and glucoseoxidase in addition to the well-known silver nitrate application. Dietary management supports the treatment. In more severe cases, topical therapies are again very useful in decreasing the healing time but fail to decrease the interval between attacks. Systemic immunomodulatory agents, like colchicine, pentoxifylline, prednisolone, dapsone, levamisol, thalidomide, azathioprine, methotrexate, cyclosporin A, interferon alpha and tumour necrosis factor (TNF) antagonists, are helpful in resistant cases of major RAS or aphthosis with systemic involvement. [source] Kaposi's sarcoma , still an enigmaJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 4 2003P Babál ABSTRACT Kaposi's sarcoma (KS) is an unusual neoplasm that has proved to be an enigma in many ways since its original description in 1872. KS, a vascular tumour that is otherwise rare, is at present the most common neoplasm in patients with AIDS. The lesions contain spindle cells that share features with endothelial cells and smooth muscle cells and are in all likelihood primitive mesenchymal cells that can form vascular channels. These cells are monoclonal in origin indicating therefore that KS is a neoplasm. The presence of a novel type of human herpes virus, KS herpesvirus (KSHV) also called human herpesvirus type 8 (HHV8) in KS lesions support a viral ethiology. KS may be mistaken in the skin for an inflammatory or other lesion, thus skin biopsy is important for correct diagnosis, with the use of immunohistochemistry or molecular biology if needed. Radiation or interferon alpha dominate in the therapeutic approaches. [source] Modulation of the anti-inflammatory interleukin 10 and of proapoptotic IL-18 in patients with chronic hepatitis C treated with interferon alpha and ribavirinJOURNAL OF VIRAL HEPATITIS, Issue 4 2006E. Marín-Serrano Summary., The aim of this work was to analyse apoptosis rate, measured by the serum levels of proapoptotic interleukin (IL)-18 and of soluble Fas (sFas), as well as of anti-inflammatory IL-10, in patients with chronic hepatitis C, at baseline and after treatment with interferon alpha and ribavirin. Twenty-seven patients with biopsy-proven chronic hepatitis C were studied, at baseline and after treatment with interferon alpha (21 cases) or pegylated interferon (6 cases) plus ribavirin. A group of 15 healthy sex- and age-matched individuals was selected as control. Serum concentrations of sFas, IL-10 and IL-18 were determined by ELISA in sandwich. The relationship of these molecules to necro-inflammatory and fibrotic activity was evaluated. Evolution of the serum concentrations of these molecules was analysed after treatment. Significantly increased serum concentrations of sFas were detected in patients with chronic hepatitis, compared with controls. Levels of this molecule were significantly correlated with necroinflammatory activity. Likewise, concentrations of IL-10 were significantly increased in the group of patients, compared with controls. Treatment with interferon and ribavirin induced a significant decrease of IL-18 concentration independently of the viral response. In contrast, levels of sFas decreased only in those patients with sustained response to therapy. Finally, baseline levels of IL-10 were significantly increased in patients without response to treatment, compared with those with sustained response, but the concentration did not change with the treatment. Increased serum levels of IL-10 are a negative prognostic marker of response to hepatitis C treatment. A significant decrease of apoptotic rate, as determined by sFas, can be expected in patients with a response to therapy. [source] Review article: hepatitis C virus and calcineurin inhibition after renal transplantationALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 8 2005F. FABRIZI Summary The impact of hepatitis C virus on patient and graft survival after renal transplantation remains controversial. However, recent studies have given emphasis on the detrimental role of hepatitis C on long-term patient and graft survival after renal transplantation. Various mechanisms can promote the lower survival in hepatitis C virus-positive recipients, i.e. post-transplant diabetes mellitus, liver disease and infections. Novel evidence has been accumulated showing the inhibitory activity of ciclosporin on the hepatitis C virus replication rate in human hepatocytes; ciclosporin has been shown in vitro to suppress hepatitis C virus replication as effectively as interferon alpha. This effect has not been seen with tacrolimus and is separate from its immunosuppressive activity. Data from patients with normal kidney function or after bone marrow transplantation show that ciclosporin inhibits hepatitis C virus replication. It appears that the progression of liver fibrosis is slower in hepatitis C virus-positive liver transplant recipients treated with ciclosporin than tacrolimus. In contrast, the clinical outcome of hepatitis C in hepatitis C virus-positive patients after liver transplantation treated with ciclosporin vs. tacrolimus has given mixed results. No information after renal transplantation is available. Various parameters can promote the worsening of hepatitis C after renal transplantation but choice of calcineurin inhibition is one of the few risk factors that can potentially be modified by the physician. Prospective, comparative trials of ciclosporin and tacrolimus with large size and adequate follow-up after renal transplantation are in progress. [source] Review article: nucleoside analogues for the treatment of chronic hepatitis BALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 11-12 2004H. M. Younger Summary Current accepted treatment for chronic hepatitis B uses either the immunomodulator interferon alpha or nucleoside analogues lamivudine or adefovir. Interferon has side effects which mean it is often poorly tolerated. Long-term use of lamivudine is associated with increasing viral resistance for each year it is taken and the rebound viraemia that can occur when the drug is stopped is also of concern to many. Adefovir appears to have less of the resistance issues of lamivudine but is still a relatively new drug and at present its use is principally limited to patients with lamivudine-resistant disease. A number of other nucleoside analogues are currently being developed with some now at the stage of early clinical trials. A proportion share the significant resistance problems of lamivudine but many appear to have more potent anti-viral effect than the drugs currently available. If some of these newer anti-viral agents are approved for use in chronic hepatitis B, the potential for prolonged suppression of hepatitis B virus replication with resultant stabilization or improvement in liver disease may be achieved. [source] Efficacy of a short-term ribavirin plus interferon alpha combination therapy followed by interferon alpha alone in previously untreated patients with chronic hepatitis C: a randomized multicenter trialLIVER INTERNATIONAL, Issue 6 2000Thomas Berg Abstract:Background: Combination therapy with interferon alpha (IFN,) plus ribavirin has been shown to improve the sustained response rate in patients with chronic hepatitis C but there is little information regarding the lengths of time for this therapeutic regimen. In this study we therefore tried to evaluate whether the analysis of different virological parameters could provide new clues with respect to the early determination of the efficacy of this form of combination therapy. Furthermore, we also examined whether short-term induction combination therapy followed by IFN, alone is more effective than monotherapy in mounting an initial as well as a sustained virological response. Methods: 185 patients with histologically proven chronic hepatitis C (mean age 42 years (range 19,65 years); 110 males, 75 females) were enrolled in the study. The patients were randomly assigned to receive, over the first 12 weeks, either interferon alpha 2a 6 million units (MU) three times weekly plus ribavirin 14 mg/kg per day (n=93) or the same dose of IFN, alone (n=92). Patients with a virological response (serum HCV RNA undetectable) after 12 weeks were subsequently treated with 3 MU IFN, alone thrice weekly for a further 40 weeks. Otherwise, treatment was discontinued. After the end of treatment, patients were followed up for 24 weeks. Results: Patient characteristics at baseline were not significantly different in the two treatment groups. An initial virological response at week 12 was seen in 61 (66%) patients receiving IFN, plus ribavirin and in 44 (48%) being treated with IFN, alone (p=0.015) and this improvement in the response rate was mainly restricted to HCV genotype 1-infected patients (58% vs. 38%). In contrast, end-of-treatment (week 52) and sustained virological response rates were similar in both groups (37% vs. 29% and 26% vs. 17% [p=0.1], respectively). Interestingly, patients with HCV genotype 3, however, clearly benefited from short-term combination therapy. Thus, sustained virological response rates in these patients significantly increased from 25% (IFN, monotherapy) to 59% (combination therapy) (p=0.05). Conclusions: Short-term combined therapy for 12 weeks is more effective than the monotherapy with respect to the induction of an initial virological response but this effect applies only to genotype 1-infected patients. However, there is no significant difference between both therapeutic schedules with regard to the induction of sustained response. Although HCV genotype 3-infected patients seem to benefit from this short-term combined therapy, prolonged combined therapy may be necessary in HCV genotype 1-infected patients. [source] Outcome of 122 pregnancies in essential thrombocythemia patients: A report from the Italian registryAMERICAN JOURNAL OF HEMATOLOGY, Issue 10 2009Lorella Melillo Pregnancy is a high-risk event in women with essential thrombocythemia (ET). This observational study evaluated pregnancy outcome in ET patients focusing on the potential impact of aspirin (ASA) or interferon alpha (IFN) treatment during pregnancy. We retrospectively analyzed 122 pregnancies in 92 women consecutively observed in the last 10 years in 17 centers of the Italian thrombocythemia registry (RIT). The live birth rate was 75.4% (92/122 pregnancies). The risk of spontaneous abortion was 2.5-fold higher than in the control population (P < 0.01). ASA did not affect the live birth rate (71/93, 76.3% vs. 21/29, 72.4%, P = 0.67). However, IFN treatment during pregnancy was associated with a better outcome than was management without IFN (live births 19/20, 95% vs. 73/102, 71.6%, P = 0.025), and this finding was supported by multivariate analysis (OR: 0.10; 95% CI: 0.013,0.846, P = 0.034). The JAK2 V617F mutation was associated with a poorer outcome (fetal losses JAK2 V617F positive 9/25, 36% vs. wild type 2/24, 8.3%, P = 0.037), and this association was still significant after multivariate analysis (OR: 6.19; 95% CI: 1.17,32.61; P = 0.038). No outcome concordance between first and second pregnancies was found (P = 0.30). Maternal complications occurred in 8% of cases. In this retrospective study, in consecutively observed pregnant ET patients, IFN treatment was associated with a higher live birth rate, while ASA treatment was not. In addition, the JAK2 V617F mutation was confirmed to be an adverse prognostic factor. Am. J. Hematol. 2009. © 2009 Wiley-Liss, Inc. [source] Low expression of interferon regulatory factor-1 and identification of novel exons skipping in patients with chronic myeloid leukaemiaBRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2002Dimitrios Tzoanopoulos Summary. Chronic myeloid leukaemia (CML) is a malignant clonal disorder of the haematopoietic stem cell. Treatment of CML patients with interferon alpha (IFN-,) has induced haematological and cytogenetic remission. Interferons transcriptionally activate target genes through the JAK,STAT and interferon regulated factors (IRFs) family pathways. Interferon regulated factor-1 (IRF-1) is a transcriptional activator of genes critical for cell growth, differentiation and apoptosis. The skipping of exons 2 or 2 and 3 of IRF-1 in patients with myelodysplastic syndromes and acute myelogenous leukaemia suggests that this factor may have a critical role in leukaemogenesis. The role of IRF-1 in CML is currently unknown. Therefore, mutational analysis of IRF-1 was performed and its expression pattern was also studied in CML patients. We studied IRF-1 in peripheral blood mononuclear cells of 21 patients in chronic phase CML. No point mutations were identified at the cDNA level. Surprisingly, fourfold reduction of full-length IRF-1 mRNA expression was established in 17/21 patients compared with normal individuals. Low expression of full-length IRF-1 was observed in conjunction with high levels of aberrantly spliced mRNAs, reported for the first time. In three patients who were also analysed during blastic transformation, further reduction of full-length IRF-1 mRNA was observed. These findings demonstrate that, in CML patients, IRF-1 can produce high levels of aberrant spliced mRNAs with subsequent reduction in the levels of full-length IRF-1 mRNA. This observation is consistent with the notion that exon skipping may constitute another mechanism of tumour suppressor gene inactivation in this disease. [source] |