CLL targeted exome sequencing
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ABSTRACT:
PROVIDER: EGAS00001001963 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Aim to characterise cancer gene landscape in CLL, particularly in cases with mutated POT1 gene. Treatment-naive CLL cases will be interrogated by targeted exome sequencing using a cancer gene panel. .
This dataset contains all the data available for this study on 2018-03-14.
| EGAD00001004037 | EGA
Project description:To identify genomic alterations contributing to the pathogenesis of high‑risk chronic lymphocytic leukemia (CLL) beyond the well‑established role of TP53 aberrations, we comprehensively analyzed 146 high‑risk CLL cases by single‑nucleotide polymorphism (SNP)‑arrays and targeted next‑generation sequencing including 75 relapsed/refractory and 71 treatment‑naïve high‑risk cases from prospective clinical trials. Increased genomic complexity was a hallmark of relapsed/refractory and treatment‑naïve high‑risk CLL, and was associated with TP53 and ATM dysfunction. In relapsed/refractory cases previously exposed to the selective pressure of chemo(immuno)therapy, gain(8)(q24.21) and del(9)(p21.3) were found particularly enriched. Both of these copy number alterations (CNAs) affected key regulators of cell cycle progression, namely c‑MYC and CDKN2A/B. Gains in 8q24.21 were either focal gains in a c‑MYC enhancer region or larger gains directly affecting the c‑MYC locus, but only the latter type was highly enriched in relapsed/refractory CLL (17%). Loss of CDKN2A/B was found frequently to co‑occur with gain of c‑MYC and in this combination it was likely associated with Richter transformation. In addition to a high frequency of NOTCH1 mutations (23%), we found recurrent genetic alterations in SPEN (4% mutated), RBPJ (8% deleted) and SNW1 (8% deleted), all affecting a protein complex that represses transcription of NOTCH1 target genes. We investigated the functional impact of these alterations on HES1, DTX1 and c‑MYC gene transcription and found de‑repression of these NOTCH1 target genes particularly with SPEN mutations. In summary, we provide new insights into the pathogenesis of high‑risk CLL by defining novel recurrent CNAs and identifying alterations that likely contribute to disease refractoriness.
2020-05-06 | GSE131114 | GEO
Project description:CD38 and CD49d are associated negative prognosticators in chronic lymphocytic leukemia (CLL). Despite evidence that both molecules are involved in interactions occurring between CLL and normal cells in the context of CLL-involved tissues, a functional link is still missing. Using gene expression profiles comparing CD38+CD49d+ vs. CD38-CD49d- CLL cells, we demonstrated overexpression of the CCL3 and CCL4 chemokines in cells from the former group. These chemokines were also upregulated by CD38 signals in CLL; moreover, CCL3 was expressed by CLL cells from bone marrow biopsies (BMB) of CD38+CD49d+ but not CD38-CD49d- cases. High levels of CCR1 and, to a lesser extent, CCR5, the receptors for CCL3 and CCL4, were found in CLL-derived monocyte-macrophages. Consistently, CCL3 increased monocyte migration, and CD68+ macrophage infiltration was particularly high in BMB from CD38+CD49d+ CLL. Conditioned media from CCL3-stimulated macrophages induced endothelial cells to express VCAM-1, the CD49d ligand, likely through TNFα over-production. These effects were apparent in BMB from CD38+CD49d+CLL, where lymphoid infiltrates were characterized by a prominent meshwork of VCAM-1+ stromal/endothelial cells. Lastly, CD49d engagement by VCAM-1-transfectants increased viability of CD38+CD49d+ CLL cells. Altogether, CD38 and CD49d can be thought of as a part of a consecutive chain of events ultimately leading to improved survival of CLL cells.
2009-03-03 | GSE14560 | GEO
Project description:NOTCH1 is mutationally activated in ~15% of cases of chronic lymphocytic leukaemia (CLL), but its role in B-cell development and leukemogenesis is not known. Here, we report that the active intracellular portion of NOTCH1 (ICN1) is detectable in ~50% of peripheral blood CLL cases lacking gene mutations. We identify a ‘NOTCH1 CLL gene expression signature’ in CLL cells, and show that this signature is significantly enriched in primary CLL cases expressing ICN1, independent of NOTCH1 mutation. NOTCH1 target genes include key regulators of B-cell proliferation, survival and signal transduction physiology. In particular, we show that MYC is a direct target of NOTCH1 via B-cell specific distal regulatory elements, thus implicating this oncogene in the pathogenesis of the disease.
2017-03-24 | GSE92626 | GEO
Project description:NOTCH1 is mutationally activated in ~15% of cases of chronic lymphocytic leukaemia (CLL), but its role in B-cell development and leukemogenesis is not known. Here, we report that the active intracellular portion of NOTCH1 (ICN1) is detectable in ~50% of peripheral blood CLL cases lacking gene mutations. We identify a ‘NOTCH1 CLL gene expression signature’ in CLL cells, and show that this signature is significantly enriched in primary CLL cases expressing ICN1, independent of NOTCH1 mutation. NOTCH1 target genes include key regulators of B-cell proliferation, survival and signal transduction physiology. In particular, we show that MYC is a direct target of NOTCH1 via B-cell specific distal regulatory elements, thus implicating this oncogene in the pathogenesis of the disease.
2017-03-24 | GSE92701 | GEO
Project description:Chronic lymphocytic leukemia (CLL) is a biologically heterogeneous illness with a variable clinical course. Loss of chromosomal material on chromosome 13 at cytoband 13q14 is the most frequent genetic abnormality in CLL, but the molecular aberrations underlying del13q14 in CLL remain incompletely characterized. We analyzed 171 CLL cases for LOH and sub-chromosomal copy loss on chromosome 13 in DNA from FACS-sorted CD19+ cells and paired buccal cells using the Affymetrix XbaI 50K SNP-array platform. The resulting high-resolution genomic maps, together with array-based measurements of expression levels of RNA in CLL cases with and without del13q14 and Q-PCR-based expression analysis of selected genes support the following conclusions: i) del13q14 is heterogeneous and composed of multiple subtypes with deletion of Rb or the miR15a/16 loci serving as anatomic landmarks, respectively ii) del13q14 type Ia deletions are relatively uniform in length and extend from breakpoints close to the miR15a/16 cluster to a newly identified telomeric breakpoint cluster at ~50.2-50.5 Mb physical position iii) LATS2 RNA levels are ~2.6-2.8-fold lower in cases with del13q14 type I that do not delete Rb as opposed to all other CLL cases and iv) ~15% of CLL cases display marked reductions in miR15a/16 expression often but not invariably associated with bi-allelic miR15a/16 loss. This data should aid future investigations into biological differences imparted on CLL by different del13q14 subtypes including investigations into LATS2 as one of the genes found deregulated as part of del13q14. Keywords: Chronic lymphocytic leukemia, CLL, gene expression comparison, del13q14, del13q
2007-10-06 | GSE9250 | GEO
Project description:Purpose: The chromosomal deletion 11q affects biology and clinical outcome in CLL but del11q-deregulated genes remain incompletely characterized. Results: We have identified differential expression of the insulin receptor (INSR) in CLL, including high-level INSR expression in the majority of CLL with del11q. High INSR mRNA expression in 11q CLL (~10-fold higher mean levels than other genomic categories) was confirmed by Q-PCR in 247 CLL cases. INSR protein measurements in 257 CLL cases through FACS, compared with measurements in normal CD19+ B-cells and monocytes, confirmed that a subset of CLL aberrantly expresses high INSR levels. We have employed integrated genomic profiling approaches upon CLL cases with and without del11q to identify 11q-relevant genes. Included are 10 primary human cases with del11q and 9 cases without del11q
2011-05-05 | E-GEOD-26526 | biostudies-arrayexpress
Project description:Purpose: The chromosomal deletion 11q affects biology and clinical outcome in CLL but del11q-deregulated genes remain incompletely characterized. Results: We have identified differential expression of the insulin receptor (INSR) in CLL, including high-level INSR expression in the majority of CLL with del11q. High INSR mRNA expression in 11q CLL (~10-fold higher mean levels than other genomic categories) was confirmed by Q-PCR in 247 CLL cases. INSR protein measurements in 257 CLL cases through FACS, compared with measurements in normal CD19+ B-cells and monocytes, confirmed that a subset of CLL aberrantly expresses high INSR levels.
2011-05-06 | GSE26526 | GEO
Project description:Stabilizing mutations of NOTCH1 have been identified in about 10% of chronic lymphocytic leukemia (CLL) cases at diagnosis, with a higher frequency in unmutated IGHV (IGHV-UM) CLL, chemorefractory CLL and CLL in advanced disease phases. Clinically, the presence of NOTCH1 mutations is an independent predictor of overall survival in CLL and associates with resistance to anti-Cd20 immunotherapy. The Gene Expression Profile was generated to identify the peculiar molecular signatures of NOTCH1 mutated CLL in the context of IGHV-UM CLL.
2016-03-01 | GSE75122 | GEO
Project description:Background: p53 plays a key role in determining the clinical features of B cell chronic lymphocytic leukemia (CLL). Disruption of p53 by point mutations, deletion at 17p13, or both, occurs in a fraction of cases at diagnosis and predicts poor survival and chemorefractoriness. In cells with functional p53, p53 activity is inhibited through interaction with MDM2. In fact, p53 can be activated upon exposure of cells to inhibitors of p53/MDM2 interaction, like Nutlins. Exposure of CLL cells to Nutlin-3 is effective in raising the levels of p53 protein with subsequent induction of cell cycle arrest and/or apoptosis, independently of the most relevant prognostic markers. Specific gene-sets and GEP were documented to be associated with response or resistance to Nutlin-3 exposure in p53(wt) or p53(del/mut) CLL. These findings may help to identify novel molecular targets for CLL therapy. Aim: to analyze the gene expression profile (GEP) induced by Nutlin-3 exposure in primary CLL cells from p53(wt) and p53(del/mut) cases. Methods: purified cells from 24 PB CLL samples, all characterized for IGHV mutational status, CD38 and ZAP-70 and p53 mutations (16 p53(wt) CLL, 8 p53(del/mut) CLL of which 6 with del17p13 and p53 mutations, 1 with del17p13 alone, and 1 with p53 mutations alone), were exposed to 10 uM Nutlin-3 for 24 hours. GEP was performed using a dual labelling strategy; the differential expression of the below reported genes were validated by quantitative real-time PCR. specific gene-sets and GEP were documented to be associated with response or resistance to Nutlin-3 exposure in p53(wt) or p53(del/mut) CLL. These findings may help to identify novel molecular targets for CLL therapy.
2009-11-11 | GSE18971 | GEO