Project description:Cytogenetically normal acute myeloid leukemia (CN-AML) comprise between forty and fifty percent of all adult acute myeloid leukemia (AML) cases. In this clinically diverse group molecular aberrations such as FLT3ITD, 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 89 CN-AML samples in a test and a validation cohort for genome-wide promoter DNA methylation with Illumina Methylation Bead arrays and compared them to normal myeloid precursors and global gene expression. IDH and NPM1 mutations were associated with different methylation patterns (p=0.0004 and 0.04, respectively). Genome-wide methylation levels were elevated in IDH mutated samples (p=0.006). 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<0.0001). Furthermore, high methylation levels of PcG target genes were independently associated with better progression free (OR 0.47, p=0.01) and overall survival (OR 0.36, p=0.001). In summary, genome wide methylation patterns show preferential methylation of PcG targets with prognostic impact in CN-AML.
Project description:Cytogenetically normal acute myeloid leukemia (CN-AML) comprise between forty and fifty percent of all adult acute myeloid leukemia (AML) cases. In this clinically diverse group molecular aberrations such as FLT3ITD, 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 89 CN-AML samples in a test and a validation cohort for genome-wide promoter DNA methylation with Illumina Methylation Bead arrays and compared them to normal myeloid precursors and global gene expression. IDH and NPM1 mutations were associated with different methylation patterns (p=0.0004 and 0.04, respectively). Genome-wide methylation levels were elevated in IDH mutated samples (p=0.006). 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<0.0001). Furthermore, high methylation levels of PcG target genes were independently associated with better progression free (OR 0.47, p=0.01) and overall survival (OR 0.36, p=0.001). In summary, genome wide methylation patterns show preferential methylation of PcG targets with prognostic impact in CN-AML. Genome wide methylation pattern study of cytogenetically normal AML
Project description:Purpose: CEBPA mutations are found as either biallelic (biCEBPA) or monoallelic (moCEBPA). We set out to explore whether the kind of CEBPA mutation is of prognostic relevance in cytogenetically normal AML (CN-AML). Patients and Methods: 467 homogeneously treated CN-AML patients were subdivided into moCEBPA, biCEBPA and wildtype (wt) CEBPA patients. The subgroups were analyzed for clinical parameters and for additional mutations in the NPM1, FLT3 and MLL genes. Furthermore, we obtained gene expression profiles (GEP) for a subgroup of 61 patients using oligonucleotide microarrays.
Project description:The study integrated both miRNA and mRNA profiles to explore novel miRNA-mRNA interactions that affect the regulatory patterns in de novo CN-AML. A total of 637 significant negative correlations (FDR <0.05) were reported. Network analysis revealed a cluster of 12 miRNAs that represents the majority of the mRNA targets. Within the cluster, five miRNAs; miR-495-3p, miR-185-5p, let-7i-5p, miR-409-3p, and miR-127-3p were suggested to play a pivotal role in the regulation of CN-AML as they are associated with negative regulation of myeloid leukocyte differentiation, negative regulation of myeloid cell differentiation, positive regulation of haematopoiesis, and hematopoiesis and its regulation. Three novel interactions in CN-AML were predicted, let-7i-5p:HOXA9, miR-495-3p:PIK3R1 and miR-495-3p:CDK6 which are responsible in regulating myeloid cell differentiation in CN-AML.
Project description:The study integrated both miRNA and mRNA profiles to explore novel miRNA-mRNA interactions that affect the regulatory patterns in de novo CN-AML. A total of 637 significant negative correlations (FDR <0.05) were reported. Network analysis revealed a cluster of 12 miRNAs that represents the majority of the mRNA targets. Within the cluster, five miRNAs; miR-495-3p, miR-185-5p, let-7i-5p, miR-409-3p, and miR-127-3p were suggested to play a pivotal role in the regulation of CN-AML as they are associated with negative regulation of myeloid leukocyte differentiation, negative regulation of myeloid cell differentiation, positive regulation of haematopoiesis, and hematopoiesis and its regulation. Three novel interactions in CN-AML were predicted, let-7i-5p:HOXA9, miR-495-3p:PIK3R1 and miR-495-3p:CDK6 which are responsible in regulating myeloid cell differentiation in CN-AML.
Project description:Chromosomal abnormalities are detected in 50-60% of patients with acute myeloid leukemia (AML) and are important predictors of prognosis and risk of relapse. The remaining patients, those with cytogenetically normal AML, are a seemingly homogeneous group that in fact consists of subsets of patients with distinct clinical outcomes. This heterogeneity is likely related to acquired gene mutations, as well as altered miRNA and gene-expression profiles, which occur within the group. The identification of recurrent molecular abnormalities has improved prognostication and provided insight into mechanisms of leukemogenesis for patients with cytogenetically normal AML, as well as led to the discovery of novel therapeutic targets. As the number of mutations continues to expand, bioinformatic algorithms that allow for integration of multiple markers will be necessary to provide optimal care for patients with this disease.
Project description:Purpose: CEBPA mutations are found as either biallelic (biCEBPA) or monoallelic (moCEBPA). We set out to explore whether the kind of CEBPA mutation is of prognostic relevance in cytogenetically normal AML (CN-AML). Patients and Methods: 467 homogeneously treated CN-AML patients were subdivided into moCEBPA, biCEBPA and wildtype (wt) CEBPA patients. The subgroups were analyzed for clinical parameters and for additional mutations in the NPM1, FLT3 and MLL genes. Furthermore, we obtained gene expression profiles (GEP) for a subgroup of 61 patients using oligonucleotide microarrays. 61 bone-marrow samples from CN-AML patients were analyzed using Affymetrix HG-U133 oligonucleotide microarrays (Affymetrix, Santa Clara, CA). Sample preparation, hybridization and image acquisition were performed according to standard Affymetrix protocols. Custom chip definition files based on the GeneAnnot database were used for data analysis (Ferrari et al, BMC Bioinformatics 8:446). The twilight algorithm was used to comapre gene expression profiles of patients with wildtype CEBPA and mono- and biallelic CEBPA mutations.
Project description:We have previously shown that expression levels of 48 long non-coding RNAs (lncRNAs) can generate a prognostic lncRNA score that independently associates with outcome of older patients (aged ≥ 60 years) with cytogenetically normal acute myeloid leukemia (CN-AML). However, the techniques that were used to identify and measure prognostic lncRNAs are not tailored for real-life clinical testing. Herein we report on an assay (based on the nCounter platform), which is designed to produce targeted measurements of prognostic lncRNAs in a clinically friendly manner. We analyzed an independent cohort of 76 older CN-AML patients and found that the nCounter assay yielded reproducible measurements and that the lncRNA score retained its prognostic value; patients with favorable lncRNA scores were more likely to achieve a complete remission (CR, P=0.009) and have longer diseased-free (DFS, P=0.05), overall (OS, P=0.02) and event-free survival (EFS, P=0.002) than patients with unfavorable lncRNA scores. In multivariable analyses, lncRNA score status independently associated with CR rates (P=0.02), as well as OS (P=0.02) and EFS (P=0.02) duration. To gain biological insights, we examined a dataset of older CN-AML patients, previously analyzed with RNA sequencing. We found genes involved in immune response and B cell receptor signaling (for which targeted inhibitors are currently available) to be enriched in patients with unfavorable lncRNA scores. We conclude that clinically applicable lncRNA profiling is feasible and potentially useful for risk stratification of older CN-AML patients. In addition we identify potentially targetable molecular pathways that are active in the high-risk patients with unfavorable lncRNA scores.
Project description:Acute myeloid leukemia (AML) is a malignant hematological disease in which nearly half have normal cytogenetics. We have tried to find some significant molecular markers for this part of the cytogenetic normal AML, which hopes to provide a benefit for the diagnosis, molecular typing and prognosis prediction of AML patients. In the present study, we calculated and compared the gene expression profiles of cytogenetically normal acute myeloid leukemia (CN-AML) patients in database of The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and dataset Vizome (a total of 632 CN-AML samples), and we have demonstrated a correlation between PDE7B gene and CN-AML. Then we proceeded to a survival analysis and prognostic risk analysis between the expression levels of PDE7B gene and CN-AML patients. The result showed that the event-free survival (EFS) and overall survival (OS) were significantly shorter in CN-AML patients with high PDE7B levels in each dataset. And we detected a significantly higher expression level of PDE7B in the leukemia stem cell (LSC) positive group. The Cox proportional hazards regression model showed that PDE7B is an independent risk predictor for CN-AML. All results indicate that PDE7B is an unfavorable prognostic factor for CN-AML.