Identification of novel sub-microscopic copy number aberrations in adult acute myeloid leukemia
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Manu Gupta
PROVIDER: E-GEOD-20672 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Mutations in the nucleophosmin 1 (NPM1) gene are considered as a founder event in the pathogenesis of acute myeloid leukemia (AML). To address the role of clonal evolution in relapsed NPM1 mutated (NPM1mut) AML, we applied high-resolution genome-wide single-nucleotide polymorphism (SNP) array profiling to detect copy number alterations (CNA) and uniparental disomies (UPD) and performed comprehensive gene mutation screening in 53 paired bone marrow/peripheral blood samples obtained at diagnosis and relapse. At diagnosis, 15 aberrations (CNAs, n=10; UPDs, n=5) were identified in 13 patients (25%), whereas at relapse 56 genomic alterations (CNAs, n=46; UPDs, n=10) were detected in 29 patients (55%) indicating an increase in genomic complexity. Recurrent aberrations acquired at relapse included deletions affecting tumor suppressor genes [ETV6 (n=3), TP53 (n=2), NF1 (n=2), WT1 (n=3), FHIT (n=2)] and homozygous FLT3 mutations acquired via UPD13q (n=7). DNMT3A mutations (DNMT3Amut) showed the highest stability (97%). Persistence of DNMT3Amut in 5 patients who lost NPM1mut at relapse suggests that DNMT3Amut may precede NPM1mut in AML pathogenesis. Of note, all relapse samples shared at least one genetic aberration with the matched primary AML sample implying common ancestral clones. In conclusion, our study reveals novel insights into clonal evolution in NPM1mut AML. Bone marrow or peripheral blood samples from diagnosis, remission and relapse of 53 NPM1 mutated AML patient were analyzed on the Affymetrix Genome-Wide Human SNP 6.0 Array. Raw data (CEL-Files) were transformed to genotyping files (CHP) with Genotyping Console Version 4.2 from Affymetrix. Bioinformatic evaluation of CNAs was performed using dChipSNP and circular binary segmentation .
2013-05-30 | E-GEOD-46951 | biostudies-arrayexpress
Project description:In this study we have screened 56 pairs of AML samples for cryptic copy number aberration and loss-of-heterozygosity. We have identified 80 CNAs among 56 patient samples; 21 containing <5 genes while 11 contained or were present within a single gene. Four (7%) patients carried gains at sub-telomeres on multiple chromosomes. Some of the cryptic regions are common with other recent studies while most are novel. Also, we show that it is better to analyse sample at diagnosis and sample at remission (paired control) both against a common unrelated control and then compare the two results than analysing the diagnostic sample directly against the paired control.
2012-03-08 | GSE20672 | GEO
Project description:To identify cooperating lesions in core-binding-factor acute myeloid leukemia (CBF-AML), we performed single-nucleotide polymorphism (SNP)-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemia samples. We identified a mean of 1.28 copy number alterations (CNAs) per case at diagnosis in both patient populations. Recurrent minimally deleted regions (MDRs) were identified at 7q36.1 (7.7%), 9q21.13 (5%), 11p13 (2.3%), and 17q11.2 (2%). Recurrent focal gains were identified at 8q24.21 (4.7%) and 11q25 (1.7%), both containing a single non-coding RNA. Recurrent regions of copy-neutral loss-of-heterozygosity were identified at 1p (1%), 4q (0.7%), and 19p (0.7%), with known mutated cancer genes present in the minimally altered region. Analysis of relapse samples identified recurrent MDRs at 3q13 (12.2%), 5q (4.9%), and 17p (4.9%). SNP genotyping was performed on 300 adult and pediatric CBF-AMLs; t(8;21), n=157 (adult, n=114; pediatric, n=43); and inv(16), n=143 (adult, n=104; pediatric, n=39). Germline control DNA from remission bone marrow or peripheral blood was available for paired analysis in 175 patients. In addition, for 41 patients, matched relapse samples were analyzed. Data were processed using reference alignment, dChipSNP and circular binary segmentation.
2012-02-07 | E-GEOD-32462 | biostudies-arrayexpress
Project description:To identify cooperating lesions in de novo and therapy-related acute myeloid leukemia (t-AML) with translocation t(9;11)(p22;q23) we performed high-resolution SNP-array profiling on 40 leukemia samples [de novo: n=22; t-AML: n=16; unknown: n=2]. A mean of 1.73 copy number alterations (CNAs)/case were identified with no differences between de novo and t-AML cases. We identified a novel minimally deleted region (MDR) at 7q36.1-q36.2 partly overlapping with a MDR previously identified in core-binding factor AML; MLL3 was the only gene affected in both regions. In addition, a recurrent gain was found at 13q21.33-q22.1 harboring the potential oncogene KLF5. Sequence/expression analysis of selected candidate genes revealed deregulated EVI1 at high frequency (50%). Copy-neutral loss-of-heterozygosity (CN-LOH) was absent in the paired cohort Further analysis of the candidate genes might provide novel insights into the pathogenesis of t(9;11) AML SNP genotyping was performed on 40 de novo and therapy-related MLL-MLLT3-rearranged acute myeloid leukemia samples; Germline control DNA from remission bone marrow or peripheral blood was available for paired analysis in 15 patients. Data were processed using reference alignment, dChipSNP and circular binary segmentation.
2014-05-22 | E-GEOD-46745 | biostudies-arrayexpress
Project description:The frequent occurrence of persistent or relapsed disease following induction chemotherapy in AML necessitates a better understanding of the clonal relationship of AML in various disease phases. In this study, we employed SNP 6.0 array-based genomic profiling of acquired copy number aberrations (aCNA) and copy neutral LOH (cnLOH) together with sequence analysis of recurrently mutated genes to characterize paired AML genomes. We analyzed 28 AML sample pairs from patients that achieved complete remission with chemotherapy and subsequently relapsed and 11 sample pairs from patients with persistent disease following induction chemotherapy. Through review of aCNA/cnLOH and gene mutation profiles in informative cases we demonstrate that relapsed AML invariably represents reemergence or evolution of a founder clone. Furthermore, all individual aCNA or cnLOH detected at presentation persisted at relapse indicating that this lesion type is proximally involved in AML evolution. Analysis of informative paired persistent AML disease samples uncovered cases with two coexisting dominant clones of which at least one was chemotherapy sensitive and one resistant, respectively. These data support the conclusion that incomplete eradication of AML founder clones rather than stochastic emergence of fully unrelated novel clones underlies AML relapse and persistence with direct implications for clinical AML research This study is based on 39 patients with AML for which either paired enrollment or relapse samples or persistent disease samples were available. The patients were enrolled into this study at the University of Michigan Comprehensive Cancer Center. The study was approved by the University of Michigan Institutional Review Board (IRBMED #2004-1022) and written informed consent was obtained from all patients prior to enrollment. Genomic DNA was extracted from purified AML blasts and paired buccal cells. DNA thus obtained was hybridized to Affymetrix SNP 6.0 arrays. Note: There is no normal sample available for MIAML015.
2013-02-12 | E-GEOD-41646 | biostudies-arrayexpress
Project description:We analysed, by last-generation high-resolution SNP arrays, Normal Karyotype (NK)-AML patients at diagnosis (Dx) and remission (R) phases, in order to determine the number of tumor-associated copy number abnormalities (CNAs) and copy neutral-loss of heterozygosity (CN-LOH) regions per patient and to identify possible recurring genomic abnormalities. The number of tumor-associated CNAs was detemined after comparison of 11 matched Dx/R samples using stringent conditions able to reduce the number of false positive CNAs. 8 additional unmatched Dx samples were included in the analysis of recurring CNAs and for detection of broad CN-LOH segments. With the exception of a single outlier case, a low number of CNAs per patient was detected (median value of 1 somatic loss or gain per patient). However, a high prevalence of CNAs (60-70% of the patients showed at least 1 tumor-associated gain or loss) and few recurring CNAs were observed, thus providing new hints towards identification of cooperating mutations. An extensive search of all CN-LOH regions > 1 Mb revealed only 3 broad regions (terminal 12Mb of 22q, terminal 27Mb of 1p and the whole chromosome 21) in three patients out of 19 (16%). CN-LOH of the whole chromosome 21 was responsible for homozygosity of a missense mutation (R80C) of RUNX1/AML1. Our study suggests that a relative submicroscopic copy number stability NK-AML genomes is associated with low recurrence of specific CNAs and CN-LOH in NK-AML patient population. Nineteen AML bone marrow samples were collected at the time of diagnosis (>90% blasts), defined as karyotypically-normal on the basis of standard metaphase cytogenetics (MC) and analysed by the Affymetrix SNP 6.0 arrays. In 11 of such cases (matched Dx) we obtained a bone marrow sample at the remission phase (matched R) of comparable high quality as evaluated by Contrast QC and MAPD values. In 8 cases (unmatched Dx) the corresponding R sample was not available or was not of comparable quality. As a reference set the publicly available data from 270 HapMap individuals were used.
2010-12-31 | E-GEOD-21780 | biostudies-arrayexpress
Project description:One lung tumor and its adjacent normal were profiled for copy-number alterations with the high-resolution Affymetrix SNP6.0 Array. The SRA ID for the high throughput sequencing project will accompany our study is SRP002045. One lung tumor sample and an adjacent normal sample were assayed on the Affymetrix SNP6.0 array.
2010-06-09 | E-GEOD-20584 | biostudies-arrayexpress
Project description:Constitutional epimutations of tumor suppressor genes manifest as promoter methylation and transcriptional silencing of a single allele in normal somatic tissues, thereby predisposing to cancer. Constitutional MLH1 epimutations occur in individuals with young-onset cancer and demonstrate non-Mendelian inheritance through their reversal in the germline. We report a cancer-affected family showing dominant transmission of soma-wide highly mosaic MLH1 methylation and transcriptional repression linked to a particular genetic haplotype. The epimutation was erased in spermatozoa but reinstated in the somatic cells of the next generation. The affected haplotype harbored two single nucleotide substitutions in tandem: c.-27C>A located near the transcription initiation site and c.85G>T. The c.-27C>A variant significantly reduced transcriptional activity in reporter assays and is the probable cause of this epimutation. Five members of a three-generation Caucasian Lynch syndrome family with an autosomal dominant MLH1 epimutation linked to a single nucleotide variant (c.-27C>A) within the MLH1 5'UTR were examined for copy number variations and retention of heterozygosity on chromosome 3. These five carriers of constitutional MLH1 methylation and the c.-27C>A variant were compared with 300 healthy Caucasian controls from the Wellcome Trust Case Control Consortium using three algorithms (QuantiSNP, PennCNV, COKGEN) to detect any copy number variants. The five family members studied were female (the proband II5, her affected mother I1, and three asymptomatic relatives II2, II4 and III2) are labeled according to the pedigree in Figure 3 of the associated publication (Hitchins et al., Cancer Cell, 2011). The supplementary file 'GSE30348_gw6.lrr_baf.txt' contains log R ratio and B-allele frequency values in a tab-delimited format with one marker per row.
2011-07-01 | E-GEOD-30348 | biostudies-arrayexpress
Project description:Genome-wide analysis of single nucleotide polymorphisms in 64 acute myeloid leukemias has revealed that 20% exhibited large regions of homozygosity that could not be accounted for by visible chromosomal abnormalities in the karyotype. Further analysis confirmed that these patterns were due to partial uniparental disomy (UPD). Remission bone marrow was available from five patients showing UPD in their leukemias, and in all cases the homozygosity was found to be restricted to the leukemic clone. Two examples of UPD11p were shown to be of different parental origin as indicated by the methylation pattern of the H19 gene. Furthermore, a previously identified homozygous mutation in the CEBPA gene coincided with a large-scale UPD on chromosome 19. These cryptic chromosomal abnormalities, which seem to be nonrandom, have the characteristics of somatic recombination events and may define an important new subclass of leukemia. Patient No. from Table 1 of Raghavan et al 2005 and Sample name; Patient No: 1 = Sample name: AML sample 35 diagnosis; Patient No: 1 = Sample name: AML sample 107 remission; Patient No: 2 = Sample name: AML sample 37 diagnosis; Patient No: 3 = Sample name: AML sample 10 diagnosis; Patient No: 3 = Sample name: AML sample 44 remission; Patient No: 4 = Sample name: AML sample 20 diagnosis; Patient No: 5 = Sample name: AML sample 65 diagnosis; Patient No: 6 = Sample name: AML sample 69 diagnosis; Patient No: 6 = Sample name: AML sample 94 remission; Patient No: 7 = Sample name: AML sample 40 diagnosis; Patient No: 7 = Sample name: AML sample 41 remission; Patient No: 8 = Sample name: AML sample 64 diagnosis; Patient No: 9 = Sample name: AML sample 7 diagnosis; Patient No: 10 = Sample name: AML sample 49 diagnosis; Patient No: 10 = Sample name: AML sample 106 remission; Patient No: 11 = Sample name: AML sample 76 diagnosis; Patient No: 12 = Sample name: AML sample 79 diagnosis Experiment Overall Design: DNA from 64 diagnostic AML samples were analysed using Affymetrix 10K SNP arrays. Large regions of homozygosity were identified and compared with remission bone marrow where available.
2008-06-15 | E-GEOD-7490 | biostudies-arrayexpress
Project description:SNP 6.0 profiles of matched plasma, tumour, and normal lymphocytes in 65 breast cancer patients and 8 female controls
2011-08-01 | E-MTAB-624 | biostudies-arrayexpress