scholarly journals Genome-wide DNA Methylation Analysis in Pediatric Acute Myeloid Leukemia

2022 ◽  
Author(s):  
Genki Yamato ◽  
Tomoko Kawai ◽  
Norio Shiba ◽  
Junji Ikeda ◽  
Yusuke Hara ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Acute Myeloid Leukemia ◽  
Adverse Events ◽  
Myeloid Leukemia ◽  
Genetic Alterations ◽  
Binding Motif ◽  
Cpg Sites ◽  
Genome Wide ◽  
Methylation Patterns ◽  
Acute Myeloid

We investigated genome-wide DNA methylation patterns in 64 pediatric patients with acute myeloid leukemia (AML). Based on unsupervised clustering with 567 most variably methylated CpG sites, patients were categorized into four clusters associated with genetic alterations. Clusters 1 and 3 were characterized by the presence of known favorable prognostic factors, such as RUNX1-RUNX1T1 fusion and KMT2A rearrangement with low MECOM expression, and biallelic CEBPA mutations (all 8 patients), respectively. Clusters 2 and 4 comprised patients exhibiting molecular features associated with adverse outcomes, namely FLT3-ITD, KMT2A-PTD, and high PRDM16 expression. Depending on the methylation values of the 1243 CpG sites that were significantly different between FLT3-ITD positive and negative AML, patients were categorized into three clusters: A, B, and C. The STAT5-binding motif was most frequently found close to the 1,243 CpG sites. All eight patients with FLT3-ITD in Cluster A harbored high PRDM16 expression and experienced adverse events, whereas only one of seven patients with FLT3-ITD in the other clusters experienced adverse events. PRDM16 expression levels were also related to DNA methylation patterns, which were drastically changed at the cutoff value of PRDM16/ABL1 = 0.10. The assay for transposase-accessible chromatin sequencing of AMLs supported enhanced chromatin accessibilities around genomic regions, such as HOXB cluster genes, SCHIP1, and PRDM16, which were associated with DNA methylation changes in AMLs with FLT3-ITD and high PRDM16 expression. Our results suggest that DNA methylation levels at specific CpG sites are useful to support genetic alterations and gene expression patterns of patients with pediatric AML.

scholarly journals Prognostic DNA methylation patterns in cytogenetically normal acute myeloid leukemia are predefined by stem cell chromatin marks

Blood ◽  
2011 ◽  
Vol 118 (20) ◽  
pp. 5573-5582 ◽  
Author(s):  
Stefan Deneberg ◽  
Philippe Guardiola ◽  
Andreas Lennartsson ◽  
Ying Qu ◽  
Verena Gaidzik ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Acute Myeloid Leukemia ◽  
Odds Ratio ◽  
Myeloid Leukemia ◽  
Negative Impact ◽  
Prognostic Impact ◽  
Aberrant Methylation ◽  
Genome Wide ◽  
Methylation Patterns ◽  
Acute Myeloid

Abstract Cytogenetically normal acute myeloid leukemia (CN-AML) compose between 40% and 50% of all adult acute myeloid leukemia (AML) cases. In this clinically diverse group, molecular aberrations, such as FLT3-ITD, NPM1, and CEBPA mutations, recently have added to the prognostic accuracy. Aberrant DNA methylation is a hallmark of cancer, including AML. We investigated in total 118 CN-AML samples in a test and a validation cohort for genome-wide promoter DNA methylation with Illumina Methylation Bead arrays and compared them with normal myeloid precursors and global gene expression. IDH and NPM1 mutations were associated with different methylation patterns (P = .0004 and .04, respectively). Genome-wide methylation levels were elevated in IDH-mutated samples (P = .006). We observed a negative impact of DNA methylation on transcription. Genes targeted by Polycomb group (PcG) proteins and genes associated with bivalent histone marks in stem cells showed increased aberrant methylation in AML (P < .0001). Furthermore, high methylation levels of PcG target genes were independently associated with better progression-free survival (odds ratio = 0.47, P = .01) and overall survival (odds ratio = 0.36, P = .001). In summary, genome-wide methylation patterns show preferential methylation of PcG targets with prognostic impact in CN-AML.

scholarly journals Investigation of measurable residual disease in acute myeloid leukemia by DNA methylation patterns

Leukemia ◽  
2021 ◽  
Author(s):  
Tanja Božić ◽  
Chao-Chung Kuo ◽  
Jan Hapala ◽  
Julia Franzen ◽  
Monika Eipel ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Residual Disease ◽  
Amplicon Sequencing ◽  
Multiparametric Flow Cytometry ◽  
Methylation Patterns ◽  
Cg Dinucleotides ◽  
Measurable Residual Disease ◽  
Acute Myeloid

AbstractAssessment of measurable residual disease (MRD) upon treatment of acute myeloid leukemia (AML) remains challenging. It is usually addressed by highly sensitive PCR- or sequencing-based screening of specific mutations, or by multiparametric flow cytometry. However, not all patients have suitable mutations and heterogeneity of surface markers hampers standardization in clinical routine. In this study, we propose an alternative approach to estimate MRD based on AML-associated DNA methylation (DNAm) patterns. We identified four CG dinucleotides (CpGs) that commonly reveal aberrant DNAm in AML and their combination could reliably discern healthy and AML samples. Interestingly, bisulfite amplicon sequencing demonstrated that aberrant DNAm patterns were symmetric on both alleles, indicating that there is epigenetic crosstalk between homologous chromosomes. We trained shallow-learning and deep-learning algorithms to identify anomalous DNAm patterns. The method was then tested on follow-up samples with and without MRD. Notably, even samples that were classified as MRD negative often revealed higher anomaly ratios than healthy controls, which may reflect clonal hematopoiesis. Our results demonstrate that targeted DNAm analysis facilitates reliable discrimination of malignant and healthy samples. However, since healthy samples also comprise few abnormal-classified DNAm reads the approach does not yet reliably discriminate MRD positive and negative samples.

Selective and Titratable Effects On AML Genome Wide Methylation Patterning, Transcription and Clonogenicity Using Very Low Concentrations of 5-Aza-2'deoxycytidine.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2385-2385
Author(s):  
Elisabeth Heuston ◽  
Jason E. Farrar ◽  
Timothy Triche ◽  
Jonathan Buckley ◽  
Poul Sorensen ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Conflicts Of Interest ◽  
Cellular Reprogramming ◽  
Transcription Profiles ◽  
Genome Wide ◽  
Low Concentrations ◽  
Xenograft Models ◽  
Methylation Patterns ◽  
Acute Myeloid

Abstract Abstract 2385 Poster Board II-362 5-Aza-2'deoxycytidine (5AzadC) has significantly contributed to the treatment of myelodysplatic syndromes (MDS) and acute myeloid leukemia (AML). But while the cytotoxic effects of 5AzadC have been well characterized, its influence on methylation-induced cellular reprogramming remains poorly understood. We have treated several AML cell lines at extremely low concentrations of 5AzadC (0 nM to 1.0 nM) over the course of three days, followed by the determination of genome wide methylation changes, alterations in transcription profiles as well as cell viability, proliferation, apoptosis and changes in clonogenicity. The results demonstrate titratable responses on both genomic methylation and transcriptional patterns as well as a selective effect on clonogenicity compared to cytotoxicity. An alternative chemotherapeutic cytosine analog, cytosine arabinofuranoside (AraC), does not show the same selective depletion of clonogenic cells, suggesting that 5AzadC's effects are likely due to altered epigenetic changes associated with cellular reprogramming rather than a direct cytotoxic effect. We are currently evaluating 5AzadC and AraC effects on this population using immunophenotyping methods as well as xenograft models of tumorigenicity. These findings describe a potential role for very low concentrations of 5AzadC in treating acute myeloid leukemia through a selective affect on genome wide methylation patterns leading to altered transcription that differentially effects the clonogenic, leukemic stem cell compartment. Disclosures: No relevant conflicts of interest to declare.

Genome-Wide Genotyping of Acute Myeloid Leukemia with t(9;11) Reveals New Recurrent Genomic Alterations,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3546-3546
Author(s):  
Michael W.M. Kühn ◽  
Lars Bullinger ◽  
Jennifer Edelmann ◽  
Jan Krönke ◽  
Gröschel Stefan ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Genetic Alterations ◽  
Mixed Lineage Leukemia ◽  
Genetic Event ◽  
Genome Wide ◽  
De Novo Aml ◽  
Paired Analysis ◽  
Acute Myeloid

Abstract Abstract 3546 Rearrangements of the mixed lineage leukemia (MLL) gene are associated with the development of acute leukemia, and a variety of translocation partners have been described to date. In acute myeloid leukemia (AML), the translocation t(9;11)(p22;q23), resulting in the MLLT3-MLL fusion gene, is the most common genetic event involving MLL. The translocation t(9;11) can occur de novo, or as a consequence of previous chemotherapy (t-AML). Both types exhibit significant biological and clinical heterogeneity, and cooperating genetic events have been implicated underlying these heterogeneous phenotypes. To identify additional genomic abnormalities in AML with t(9;11), we performed high-resolution, genome-wide analysis of DNA copy number alterations (CNA) and copy neutral loss of heterozygosity (CN-LOH) using Affymetrix 6.0 single nucleotide polymorphism (SNP) microarrays in 34 AMLs with t(9;11) [de novo AML, n=22; t-AML, n=12]. Samples were also analyzed for AML-associated mutations: FLT3 [internal tandem duplication (ITD; 2/33); tyrosine kinase domain (TKD; 2/26)], NPM1 (0/28), CEBPA (0/23), IDH1 (0/28), IDH 2 (0/28), DNMT3A (0/19), NRAS (0/6); and deregulated expression of EVI1 (8/16). Control DNA from remission bone marrow or peripheral blood was available for paired analysis in 12 (33%) cases. Data were processed using reference alignment, dChipSNP, and circular binary segmentation. Paired analysis revealed a mean of 1.9 somatic CNAs per case (range: 0–12); 45% of cases lacked any CNAs. Deletions were more common than gains (1.73 losses/case vs. 0.25 gains/case; p =0.04). There were no significant differences in the mean number of CNAs between de novo and therapy-related cases (de novo AML: 1.0, range: 0–2; t-AML: 2.7, range: 0–12; p =0.93). Recurrent deletions were detected at chromosomal bands 7q36.1–36.2 (n=2) and at the chromosomal translocation breakpoint at 11q23 (n=2). The del(7q36.1–36.2) overlapped with a minimally deleted region at 7q36.1 that we previously identified in 8% of core-binding factor AML containing only 4 genes (PRKAG2, GALNT11, GALNTL5 and MLL3). The only gene contained in both regions was MLL3, a member of the mixed-lineage leukemia gene family. The most recurrent CNA was trisomy 8 (n=5), also detected by conventional cytogenetics in all 5 cases. Novel recurrent focal gains were identified at 9p22.1 (n=2; size: 341 Kb) and at 13q21.33-q22.1 (n=2; size: 1021 Kb) with each region containing genes potentially involved in cancer pathogenesis (ACER2 in 9p; KLF5 in 13q). Analysis of CN-LOH revealed no such lesion in any of the cases. In summary, our data provide a comprehensive survey of CNAs in a well characterized cohort of AMLs with t(9;11). These data demonstrate a very low occurrence of CNAs, with no significant differences between de novo and therapy-related cases and complete absence of CN-LOH. Interestingly, a number of novel recurrent secondary genetic alterations were identified. Determining the functional role of these lesions in leukemogenesis and drug resistance should provide new insights into t(9;11)-bearing AMLs. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Genome-wide regulation of CpG methylation by ecCEBPα in acute myeloid leukemia

F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 204
Author(s):  
Adewale J. Ogunleye ◽  
Ekaterina Romanova ◽  
Yulia A. Medvedeva
Keyword(s):  
Dna Methylation ◽  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Cpg Methylation ◽  
The Cancer Genome Atlas ◽  
Binding Potential ◽  
Hematopoietic Malignancy ◽  
Genome Wide ◽  
A Genome ◽  
Acute Myeloid

Background: Acute myeloid leukemia (AML) is a hematopoietic malignancy characterized by genetic and epigenetic aberrations that alter the differentiation capacity of myeloid progenitor cells. The transcription factor CEBPα is frequently mutated in AML patients leading to an increase in DNA methylation in many genomic locations. Previously, it has been shown that ecCEBPα (extra coding CEBPα) - a lncRNA transcribed in the same direction as CEBPα gene - regulates DNA methylation of CEBPα promoter in cis. Here, we hypothesize that ecCEBPα could participate in the regulation of DNA methylation in trans. Method: First, we retrieved the methylation profile of AML patients with mutated CEBPα locus from The Cancer Genome Atlas (TCGA). We then predicted the ecCEBPα secondary structure in order to check the potential of ecCEBPα to form triplexes around CpG loci and checked if triplex formation influenced CpG methylation, genome-wide. Results: Using DNA methylation profiles of AML patients with a mutated CEBPα locus, we show that ecCEBPα could interact with DNA by forming DNA:RNA triple helices and protect regions near its binding sites from global DNA methylation. Further analysis revealed that triplex-forming oligonucleotides in ecCEBPα are structurally unpaired supporting the DNA-binding potential of these regions. ecCEBPα triplexes supported with the RNA-chromatin co-localization data are located in the promoters of leukemia-linked transcriptional factors such as MLF2. Discussion: Overall, these results suggest a novel regulatory mechanism for ecCEBPα as a genome-wide epigenetic modulator through triple-helix formation which may provide a foundation for sequence-specific engineering of RNA for regulating methylation of specific genes.

scholarly journals Genome-wide regulation of CpG methylation by ecCEBPα in acute myeloid leukemia

F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 204
Author(s):  
Adewale J. Ogunleye ◽  
Ekaterina Romanova ◽  
Yulia A. Medvedeva
Keyword(s):  
Dna Methylation ◽  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Cpg Methylation ◽  
The Cancer Genome Atlas ◽  
Binding Potential ◽  
Hematopoietic Malignancy ◽  
Genome Wide ◽  
A Genome ◽  
Acute Myeloid

Background: Acute myeloid leukemia (AML) is a hematopoietic malignancy characterized by genetic and epigenetic aberrations that alter the differentiation capacity of myeloid progenitor cells. The transcription factor CEBPα is frequently mutated in AML patients leading to an increase in DNA methylation in many genomic locations. Previously, it has been shown that ecCEBPα (extra coding CEBPα) - a lncRNA transcribed in the same direction as CEBPα gene - regulates DNA methylation of CEBPα promoter in cis. Here, we hypothesize that ecCEBPα could participate in the regulation of DNA methylation in trans. Method: First, we retrieved the methylation profile of AML patients with mutated CEBPα locus from The Cancer Genome Atlas (TCGA). We then predicted the ecCEBPα secondary structure in order to check the potential of ecCEBPα to form triplexes around CpG loci and checked if triplex formation influenced CpG methylation, genome-wide. Results: Using DNA methylation profiles of AML patients with a mutated CEBPα locus, we show that ecCEBPα could interact with DNA by forming DNA:RNA triple helices and protect regions near its binding sites from global DNA methylation. Further analysis revealed that triplex-forming oligonucleotides in ecCEBPα are structurally unpaired supporting the DNA-binding potential of these regions. ecCEBPα triplexes supported with the RNA-chromatin co-localization data are located in the promoters of leukemia-linked transcriptional factors such as MLF2. Discussion: Overall, these results suggest a novel regulatory mechanism for ecCEBPα as a genome-wide epigenetic modulator through triple-helix formation which may provide a foundation for sequence-specific engineering of RNA for regulating methylation of specific genes.

scholarly journals Aberrant DNA Methylation in Acute Myeloid Leukemia and Its Clinical Implications

2019 ◽  
Vol 20 (18) ◽  
pp. 4576 ◽  
Author(s):  
Xianwen Yang ◽  
Molly Pui Man Wong ◽  
Ray Kit Ng
Keyword(s):  
Dna Methylation ◽  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Epigenetic Modification ◽  
Critical Role ◽  
Genetic Alterations ◽  
Dna Methyltransferases ◽  
Clinical Implications ◽  
Aberrant Dna Methylation ◽  
Acute Myeloid

Acute myeloid leukemia (AML) is a heterogeneous disease that is characterized by distinct cytogenetic or genetic abnormalities. Recent discoveries in cancer epigenetics demonstrated a critical role of epigenetic dysregulation in AML pathogenesis. Unlike genetic alterations, the reversible nature of epigenetic modifications is therapeutically attractive in cancer therapy. DNA methylation is an epigenetic modification that regulates gene expression and plays a pivotal role in mammalian development including hematopoiesis. DNA methyltransferases (DNMTs) and Ten-eleven-translocation (TET) dioxygenases are responsible for the dynamics of DNA methylation. Genetic alterations of DNMTs or TETs disrupt normal hematopoiesis and subsequently result in hematological malignancies. Emerging evidence reveals that the dysregulation of DNA methylation is a key event for AML initiation and progression. Importantly, aberrant DNA methylation is regarded as a hallmark of AML, which is heralded as a powerful epigenetic marker in early diagnosis, prognostic prediction, and therapeutic decision-making. In this review, we summarize the current knowledge of DNA methylation in normal hematopoiesis and AML pathogenesis. We also discuss the clinical implications of DNA methylation and the current therapeutic strategies of targeting DNA methylation in AML therapy.

scholarly journals Genome-Wide Mapping and Subtype Classification of Long Non-Coding RNA in Acute Myeloid Leukemia

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2355-2355
Author(s):  
Rong Chen ◽  
Gabriel G Malouf ◽  
Jianping Zhang ◽  
Xuelin Huang ◽  
John N Weinstein ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Conflicts Of Interest ◽  
Genetic Alterations ◽  
Cell Physiology ◽  
Fusion Transcripts ◽  
Subtype Classification ◽  
Genome Wide ◽  
Acute Myeloid

Abstract Background: Most efforts to characterize acute myeloid leukemia (AML) have focused so far on genetic and epigenetic aberrations, which can ultimately lead to altered protein-coding gene function. The roles of long non-coding RNAs (lncRNAs), which orchestrate cell physiology and act as key regulators of the AML oncogenic state, remain uncharacterized globally. Material and Methods: We performed a genomic analysis of GENCODE lncRNAs in 179 clinically annotated cases of de novo AML, using The Cancer Genome Atlas (TCGA) RNA-Seq data. In addition, we described global correlations between lncRNAs and the expression of cis- and trans-acting genes. We also established lncRNA-based subtype classification based on distinct signatures and then correlated that classification with fusion transcripts and genetic alterations. Results: Using stringent criteria (RPKM ≥1 in at least 10% of AML), we identified 2,913 expressed lncRNAs and used an integrative analysis to predict those that are potential regulators of AML oncogenic state. The expression of 1,935 (66.4%) lncRNAs showed positive correlations with the mRNA expression of their neighboring genes, while only 14 (0.4%) of the lncRNAs showed negative correlations. Gene ontology analysis using GREAT revealed enrichment of cis-neighboring genes in the PML body gene set (p=8.2x10-7). Unsupervised clustering of lncRNA-based expression showed five robust molecular clusters (C1 to C5), which were highly correlated with the mRNA-based classification. Of those, three clusters (C1, C2 and C5) were tightly associated with recurrent fusion transcripts; cluster C1 (n=16) was composed exclusively of promyelocytic leukemias, while cluster C5 (n=45) was enriched for MLL-rearranged cases (24.4%), and cluster C2 (n=31) was enriched for MYH11-CBFB or RUNX1-RUNX1T1 (55.2%) rearranged cases. Importantly, cluster C4 (n=30), which includes cytogenetically normal leukemias, was highly enriched for NPM1 (p=2.3x10-11) and FLT3 (p=1.6x10-4) mutations; conversely, cluster C3 (n=53) was highly enriched for recurrent copy-number alterations as well as RUNX1 (p=0.001) and TP53 somatic mutations (p=0.004). We further discovered a core of 37 lncRNAs significantly associated with a MLL-signature and 16 lncRNAs with a NPM1-mutated signature. Conclusion: This study describes the first genome-wide mapping and characterization of lncRNAs in AML and proposes a robust lncRNA-based classification. This classification may serve in defining core lncRNAs that orchestrate key oncogenic states in the different clinical subtypes. Disclosures No relevant conflicts of interest to declare.

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