Comparison of Chronic Lymphocytic Leukemia patients expressing high or low levels of ZAP70 mRNA
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ABSTRACT: Comparison of Chronic Lymphocytic Leukemia patients expressing high or low levels of ZAP70 mRNA: prognostic factors and interaction with the microenvironment. Zeta-associated protein 70 (ZAP70) is a widely recognized prognostic factor in chronic lymphocytic leukemia (CLL), but mechanisms by which its higher expression leads to a poor outcome remain to be fully explained. In an attempt to unveil unfavorable cellular properties linked to high ZAP70 expression, we used gene expression profiling to identify genes associated with disparities in B-cells from CLL patients expressing high versus low ZAP70 mRNA, measured by quantitative real-time PCR. Keywords: comparison of poor and good prognosis CLL patient transcriptome regarding ZAP70 expression
Project description:Comparison of Chronic Lymphocytic Leukemia patients expressing high or low levels of ZAP70 mRNA: prognostic factors and interaction with the microenvironment. Zeta-associated protein 70 (ZAP70) is a widely recognized prognostic factor in chronic lymphocytic leukemia (CLL), but mechanisms by which its higher expression leads to a poor outcome remain to be fully explained. In an attempt to unveil unfavorable cellular properties linked to high ZAP70 expression, we used gene expression profiling to identify genes associated with disparities in B-cells from CLL patients expressing high versus low ZAP70 mRNA, measured by quantitative real-time PCR. Experiment Overall Design: Two groups of seven CLL patients were compared, selected on the basis of either high or low ZAP70 mRNA expression. Total RNA from CD19+ purified cells was exctracted and hybidyzed on Affymetrix GeneChipî Human Genome U133 Plus 2.0 Array. Amplification, hybridization and scanning were done according to standard Affymetrix protocols (www.affymetrix.com). CEL files were ,normalized with RMA method.
Project description:Chronic lymphocytic leukemia (CLL) is a disease with a highly variable prognosis. The clinical course can however be predicted thanks to prognostic markers. Poor prognosis is associated with expression of a B cell receptor (BCR) from unmutated immunoglobulin variable heavy-chain genes (IgVH) and expression of zeta associated protein of 70 kDa (ZAP-70). The reason why ZAP-70 expression is associated with poor prognosis and whether the protein has a direct pathogenic function is at present unknown. By transfer of ZAP-70 to CLL cells, we show here that expression of ZAP-70 in CLL cells leads to increased expression of the NF-κB target genes interleukin-1β (IL-1β), IL-6 and IL-8 upon BCR triggering. This could be blocked by inhibition of NF-κB signaling through inhibition of IκB kinases (IKK). Transcriptome analysis identified a NF-κB RelA signature imposed by ZAP-70 expression in BCR stimulated CLL cells. We conclude that ZAP-70 acts directly as an amplifier of NF-κB signaling in CLL cells which could be an underlying mechanism for its association with poor prognosis and which may represent a therapeutic target.
Project description:B cell chronic lymphocytic leukemia - A model with immune response
Seema Nanda 1, , Lisette dePillis 2, and Ami Radunskaya 3,
1.
Tata Institute of Fundamental Research, Centre for Applicable Mathematics, Bangalore 560065, India
2.
Department of Mathematics, Harvey Mudd College, Claremont, CA 91711
3.
Department of Mathematics, Pomona College, Claremont, CA, 91711, United States
Abstract
B cell chronic lymphocytic leukemia (B-CLL) is known to have substantial clinical heterogeneity. There is no cure, but treatments allow for disease management. However, the wide range of clinical courses experienced by B-CLL patients makes prognosis and hence treatment a significant challenge. In an attempt to study disease progression across different patients via a unified yet flexible approach, we present a mathematical model of B-CLL with immune response, that can capture both rapid and slow disease progression. This model includes four different cell populations in the peripheral blood of humans: B-CLL cells, NK cells, cytotoxic T cells and helper T cells. We analyze existing data in the medical literature, determine ranges of values for parameters of the model, and compare our model outcomes to clinical patient data. The goal of this work is to provide a tool that may shed light on factors affecting the course of disease progression in patients. This modeling tool can serve as a foundation upon which future treatments can be based.
Keywords: NK cell, chronic lymphocytic leukemia, mathematical model, T cell., B-CLL.
Project description:Chronic lymphocytic leukemia (CLL) is a disease with a highly variable prognosis. The clinical course can however be predicted thanks to prognostic markers. Poor prognosis is associated with expression of a B cell receptor (BCR) from unmutated immunoglobulin variable heavy-chain genes (IgVH) and expression of zeta associated protein of 70 kDa (ZAP-70). The reason why ZAP-70 expression is associated with poor prognosis and whether the protein has a direct pathogenic function is at present unknown. By transfer of ZAP-70 to CLL cells, we show here that expression of ZAP-70 in CLL cells leads to increased expression of the NF-M-NM-:B target genes interleukin-1M-NM-2 (IL-1M-NM-2), IL-6 and IL-8 upon BCR triggering. This could be blocked by inhibition of NF-M-NM-:B signaling through inhibition of IM-NM-:B kinases (IKK). Transcriptome analysis identified a NF-M-NM-:B RelA signature imposed by ZAP-70 expression in BCR stimulated CLL cells. We conclude that ZAP-70 acts directly as an amplifier of NF-M-NM-:B signaling in CLL cells which could be an underlying mechanism for its association with poor prognosis and which may represent a therapeutic target. 22 patient samples, Stimulated for 3h or 24h, Electroporated with capped ZAP-70 mRNA or uncapped ZAP-70 mRNA (negative control)
Project description:This study investigates genomic imbalance in chronic lymphocytic leukemia (CLL) and aims to identify genomic gains and losses with prognostic significance.
Project description:This study investigates genomic imbalance in chronic lymphocytic leukemia (CLL) and aims to identify genomic gains and losses with prognostic significance. Two-condition experiment, Test CLL specimens vs. Reference human genome DNA equimixture of normal male and normal female.
Project description:LPL co-deregulated genes after LPL specific siRNA knock-down In chronic lymphocytic leukemia (CLL), lipoprotein lipase (LPL) mRNA overexpression is an established poor prognostic marker, its function, however, is poorly understood. Measuring extracellular LPL enzymatic activity and protein, we found no difference between levels in CLL patients and those of controls, both before and after heparin treatment in vivo and in vitro. Investigating LPL knock down effects, we determined five potential downstream targets, of which one gene, STXBP3, reportedly is involved in fatty acid metabolism. While possibly reflecting an epigenetic switch towards an incorrect transcriptional program, LPL overexpression by itself does not appear to significantly influence CLL cell survival.
Project description:LPL co-deregulated genes after LPL specific siRNA knock-down In chronic lymphocytic leukemia (CLL), lipoprotein lipase (LPL) mRNA overexpression is an established poor prognostic marker, its function, however, is poorly understood. Measuring extracellular LPL enzymatic activity and protein, we found no difference between levels in CLL patients and those of controls, both before and after heparin treatment in vivo and in vitro. Investigating LPL knock down effects, we determined five potential downstream targets, of which one gene, STXBP3, reportedly is involved in fatty acid metabolism.
Project description:Chronic lymphocytic leukemia (CLL) is a common and heterogeneous disease. An accurate prediction of outcome is highly relevant for the development of personalized treatment strategies. Microarray technology was shown to be a useful tool for the development of prognostic gene expression scores. However, there are no gene expression scores which are able to predict overall survival in CLL based on the expression of few genes that are better than established prognostic markers. We correlated 151 CLL microarray data sets with overall survival using Cox regression and supervised principal component analysis to derive a prognostic score. This score based on the expression levels of eight genes and was validated in an independent group of 149 CLL patients by quantitative real time PCR. The score was predictive for overall survival and time to treatment in univariate Cox regression in the validation data set (both: p<0.001) and in a multivariate analysis after adjustment for 17p and 11q deletions and the IgVH-status. The score achieved superior prognostic accuracy compared to models based on genomic aberrations and IgVH-status and may support personalized therapy. Analysis of 151 samples of peripheral blood mononuclear cells (107 HGU-133plus2; 44 HGU-133A; 44 HGU-133B) from adult patients with chronic lymphocytic leukemia (CLL)
Project description:In chronic lymphocytic leukemia (CLL), 13q14 and 11q22-23 deletions are found in 2/3 of the cases. 11q22-23 deletions are associated with poor survival, whereas 13q14 deletions as single abnormality are often found in indolent disease forms. The molecular basis for this difference in prognosis is not known. ARHGAP20 encodes an evolutionarily conserved protein. In the zebra fish (Danio rerio) genome the syntenic regions of human chromosomal bands 13q14 and 11q22-23 are juxtaposed. The similar expression profiles of ARHGAP20 in 13q14 and 11q22-23 deleted CLL cases suggest a molecular connection and an intriguing mechanism of regulation. Analysis of 154 samples of peripheral blood mononuclear cells (109 HGU-133plus2; 45 HGU-133A; 45 HGU-133B) from adult patients with chronic lymphocytic leukemia (CLL).