Genomic effects of once-weekly, intramuscular interferon-β1a treatment after the first dose and on chronic dosing: Relationships to 5-year clinical outcomes in multiple sclerosis patients
Jacobs Neurological Institute, Buffalo General Hospital, Buffalo, NY 14203, United States. Journal of Neuroimmunology
(Impact Factor: 2.47).
11/2008; 205(1-2):113-25. DOI: 10.1016/j.jneuroim.2008.09.004
To characterize gene expression in multiple sclerosis (MS) patients after the first dose and chronic dosing of 30 microg, once weekly, intramuscular interferon-beta1a (IFN-beta) and to delineate the pharmacogenomic differences between Good Responders and Partial Responders to IFN-beta therapy.
The treatment responses after the first IFN-beta dose and chronic IFN-beta dosing were assessed in 22 relapsing MS patients (17 females, 5 males; average age: 41.5+/-SD 10.4 years). Gene expression profiles in peripheral blood mononuclear cells were obtained prior to treatment and at 1, 2, 4, 8, 24, 48, 120, 168 h after the first IFN-beta dose and at 1, 6 and 12 months after chronic dosing with once-weekly 30 microg IFN-beta-1a intramuscularly. Repeated measures statistics with false discovery rate control were used. The functional characteristics, biological pathways and transcription factor sites were analyzed.
Of the 1000 genes modulated following the first dose and upon chronic dosing of IFN-beta in MS patients, approximately 35% were up-regulated and 65% were down- regulated; the percentage of modulated genes in common was approximately 50%. The expression of the pharmacodynamic mRNA markers of IFN-beta effect showed differences in time profiles for the Good Responder and Partial Responders to IFN-beta therapy and the Jak-STAT, TNFRSF10B, IL6, TGFbeta, retinoic acid and CDC42 pathways were differentially modulated. The patients with side effects to therapy showed differences in the TGFbeta1, IFNG/STAT3 and TNF pathways.
Gene expression is a valuable tool for understanding the molecular mechanisms of IFN-beta action in MS patients.
Available from: Anna Feldman
- "Previous studies using peripheral blood gene expression arrays characterized MS pathogenesis, progression and response to treatment –. "
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ABSTRACT: Benign multiple sclerosis (BMS) occurs in about 15% of patients with relapsing-remitting multiple sclerosis (RRMS) that over time do not develop significant neurological disability. The molecular events associated with BMS are not clearly understood. This study sought to underlie the biological mechanisms associated with BMS. Blood samples obtained from a cohort of 31 patients with BMS and 36 patients with RRMS were applied for gene expression microarray analysis using HG-U133A-2 array (Affymetrix). Data were analyzed by Partek and pathway reconstruction was performed by Ingenuity for the most informative genes (MIGs). We identified a differing gene expression signature of 406 MIGs between BMS patients, mean±SE age 44.5±1.5 years, 24 females, 7 males, EDSS 1.9±0.2, disease duration 17.0±1.3 years, and RRMS patients, age 40.3±1.8 years, 24 females, 12 males, EDSS 3.5±0.2, disease duration 10.9±1.4 years. The signature was enriched by genes related RNA polymerase I (POL-1) transcription, general inflammatory response and activation of cell death. The most significant under-expressed pathway operating in BMS was the POL-1 pathway (p = 4.0*10(-5)) known while suppressed to activate P53 dependent apoptosis and to suppress NFκB induced inflammation. In accordance, of the 30 P53 target genes presented within the BMS signature, 19 had expression direction consistent with P53 activation. The transcripts within the pathway include POL-1 transcription factor 3 (RRN3, p = 4.8*10(-5)), POL-1 polypeptide D (POLR1D, p = 2.2*10(-4)), leucine-rich PPR-motif containing protein (LRPPRC p = 2.3*10(-5)), followed by suppression of the downstream family of ribosomal genes like RPL3, 6,13,22 and RPS6. In accordance POL-1 transcript and release factor PTRF that terminates POL-1 transcription, was over-expressed (p = 4.4*10(-3)). Verification of POL-1 pathway key genes was confirmed by qRT-PCR, and RRN3 silencing resulted in significant increase in the apoptosis level of PBMC sub-populations in RRMS patients. Our findings demonstrate that suppression of POL-1 pathway induce the low disease activity of BMS.
Available from: Per Soelberg Soerensen
- "The sample size was based on previous studies on the effects of IFN-β in small patient cohorts and on studies reporting that gene expression profiling in 22 MS patients could identify subgroups with different disease courses during treatment with IFN-β –. Values are given as median with inter-quartile range. Statistical testing was by the Wilcoxon test, the Mann-Whitney U-test, paired t-test, non-parametric correlation analysis (Spearman rank correlation coefficient [SRCC]), Cox regression analysis (hazard ratio with 95% confidence interval), the log-rank test and Kaplan-Meier plots. "
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ABSTRACT: Although treatment of multiple sclerosis (MS) with the type I interferon (IFN) IFN-β lowers disease activity, the role of endogenous type I IFN in MS remains controversial. We studied CD4+ T cells and CD4+ T cell subsets, monocytes and dendritic cells by flow cytometry and analysed the relationship with endogenous type I IFN-like activity, the effect of IFN-β therapy, and clinical and magnetic resonance imaging (MRI) disease activity in MS patients. Endogenous type I IFN activity was associated with decreased expression of the integrin subunit CD49d (VLA-4) on CD4+CD26(high) T cells (Th1 helper cells), and this effect was associated with less MRI disease activity. IFN-β therapy reduced CD49d expression on CD4+CD26(high) T cells, and the percentage of CD4+CD26(high) T cells that were CD49d(high) correlated with clinical and MRI disease activity in patients treated with IFN-β. Treatment with IFN-β also increased the percentage of CD4+ T cells expressing CD71 and HLA-DR (activated T cells), and this was associated with an increased risk of clinical disease activity. In contrast, induction of CD71 and HLA-DR was not observed in untreated MS patients with evidence of endogenous type IFN I activity. In conclusion, the effects of IFN-β treatment and endogenous type I IFN activity on VLA-4 expression are similar and associated with control of disease activity. However, immune-activating effects of treatment with IFN-β may counteract the beneficial effects of treatment and cause an insufficient response to therapy.
Available from: Hans-Jürgen Thiesen
- "In return, the exploration of potential targets and PBMC biomarkers arising from one year therapy monitoring is absolutely unbiased, in contrast to knowledge-based models. An ambitious highthroughput gene expression profiling project for long-term IFNB therapy has been recently performed by Weinstock-Guttman et al.  comprising 11 timecourse checkpoints and extending to 12 months of therapy with IFNB1a. Our study tries to partially reproduce this kind of exploratory analysis in a sample of the German population for IFNB1b. "
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ABSTRACT: Despite its generalized use as drug therapy for multiple sclerosis (MS), the molecular mechanisms of action of interferon beta (IFNB) are still poorly understood. IFNB therapy is long-termed and clinical effects are not immediate, therefore reliable early biomarkers for IFNB activity should maintain a differential expression over time, but longitudinal studies at a transcriptional level have been rare. Microarrays were used to monitor 18 IFNB1b treated MS patients at four time points spanning a period of 1 year. Genes showing in the majority of patients the greatest and most consistent changes in their expression levels were studied. Interferon regulated genes were significantly overrepresented. Fifteen markers were differentially expressed during all three time points and followed a consistent time course pattern: EIF2AK2, IFI6, IFI44, IFI44L, IFIH1, IFIT1, IFIT2, IFIT3, ISG15, MX1, OASL, RSAD2, SN, XAF1 and the marker 238704_at. Except for the last one, these biomarkers were all formerly identified as being indicative for IFNB activity. Expression changes were both early detectable and long lasting and could thus be optimal biomarkers for IFNB activity in long-term studies. Other known biomarkers of IFNB activity were found to be differentially expressed just for certain periods after therapy onset: Interleukin-8 was a short lasting marker and changes in STAT1 were detected with delay.
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