Project description:Gene expression in NPM1 wildtype and mutated AML patients with high or low hsa_circ_0075001 expression In acute myeloid leukemia there is growing evidence for splicing pattern deregulation, including differential expression of linear splice isoforms of the commonly mutated gene nucleophosmin (NPM1). In this study, we detect circular RNAs of NPM1 and quantify circRNA hsa_circ_0075001 in a cohort of NPM1 wildtype and mutated acute myeloid leukemia (n=46). Hsa_circ_0075001 expression correlates positively with total NPM1 expression, but is independent of the NPM1 mutational status. High versus low hsa_circ_0075001 expression defines patient subgroups characterized by distinct gene expression patterns, such as lower expression of components of the Toll-like receptor signaling pathway in high hsa_circ_0075001 expression cases. Global evaluation of circRNA expression in sorted healthy hematopoietic controls (n=10) and acute myeloid leukemia (n=10) reveals circRNA transcripts for 47.9% of all highly expressed genes. While circRNA expression correlates globally with parental gene expression, we identify hematopoietic differentiation-associated as well as acute myeloid leukemia subgroup-specific circRNA signatures.
Project description:In acute myeloid leukemia, there is growing evidence for splicing pattern deregulation, including differential expression of linear splice isoforms of the commonly mutated gene nucleophosmin (NPM1). In this study, we detect circular RNAs of NPM1 and quantify circRNA hsa_circ_0075001 in a cohort of NPM1 wild-type and mutated acute myeloid leukemia (n=46). Hsa_circ_0075001 expression correlates positively with total NPM1 expression, but is independent of the NPM1 mutational status. High versus low hsa_circ_0075001 expression defines patient subgroups characterized by distinct gene expression patterns, such as lower expression of components of the Toll-like receptor signaling pathway in high hsa_circ_0075001 expression cases. Global evaluation of circRNA expression in sorted healthy hematopoietic controls (n=10) and acute myeloid leukemia (n=10) reveals circRNA transcripts for 47.9% of all highly expressed genes. While circRNA expression correlates globally with parental gene expression, we identify hematopoietic differentiation-associated as well as acute myeloid leukemia subgroup-specific circRNA signatures.
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 .
Project description:Mutation in the nucleophosmin (NPM1) gene is frequent in acute myeloid leukemia (AML). This mutation has remarkable prognostic significance and correlates with distinct biological features. Our data from the sample-paired microRNA (miRNA) and mRNA microarrays of de novo AML patients strongly indicated that miRNAâmRNA regulation (MMR) may be dynamic and can be modulated by NPM1 mutation. We identified 493 NPM1 mutation-modulated MMR pairs by a systematic framework, in which MMR was attenuated specifically in patients carrying NPM1 mutations. The involved miRNAs/mRNAs were associated with cancer and hematological diseases, as well as known functions of NPM1 mutation including cell death and cellular response to therapeutics. The NPM1 mutation modulation could be validated with three approaches, including two independent cohort datasets, a high-throughput dataset derived from cell line-based experiments, and two in vitro models. Our study provides novel biological insights into the role of NPM1 mutation as a modulator of MMR, based on which novel prognostic markers are derived in AML. Cryopreserved bone marrow cells were obtained from 109 de novo AML patients. Each sample was analyzed with Illumina HumanHT-12 V4.0 expression beadchip.
Project description:Mutation in the nucleophosmin (NPM1) gene is frequent in acute myeloid leukemia (AML). This mutation has remarkable prognostic significance and correlates with distinct biological features. Our data from the sample-paired microRNA (miRNA) and mRNA microarrays of de novo AML patients strongly indicated that miRNAâmRNA regulation (MMR) may be dynamic and can be modulated by NPM1 mutation. We identified 493 NPM1 mutation-modulated MMR pairs by a systematic framework, in which MMR was attenuated specifically in patients carrying NPM1 mutations. The involved miRNAs/mRNAs were associated with cancer and hematological diseases, as well as known functions of NPM1 mutation including cell death and cellular response to therapeutics. The NPM1 mutation modulation could be validated with three approaches, including two independent cohort datasets, a high-throughput dataset derived from cell line-based experiments, and two in vitro models. Our study provides novel biological insights into the role of NPM1 mutation as a modulator of MMR, based on which novel prognostic markers are derived in AML. Cryopreserved bone marrow cells were obtained from 109 de novo AML patients. Each sample was analyzed with nCounter® Human miRNA Expression Array.
Project description:Mutation in the nucleophosmin (NPM1) gene is frequent in acute myeloid leukemia (AML). This mutation has remarkable prognostic significance and correlates with distinct biological features. Our data from the sample-paired microRNA (miRNA) and mRNA microarrays of de novo AML patients strongly indicated that miRNA−mRNA regulation (MMR) may be dynamic and can be modulated by NPM1 mutation. We identified 493 NPM1 mutation-modulated MMR pairs by a systematic framework, in which MMR was attenuated specifically in patients carrying NPM1 mutations. The involved miRNAs/mRNAs were associated with cancer and hematological diseases, as well as known functions of NPM1 mutation including cell death and cellular response to therapeutics. The NPM1 mutation modulation could be validated with three approaches, including two independent cohort datasets, a high-throughput dataset derived from cell line-based experiments, and two in vitro models. Our study provides novel biological insights into the role of NPM1 mutation as a modulator of MMR, based on which novel prognostic markers are derived in AML.
Project description:Mutation in the nucleophosmin (NPM1) gene is frequent in acute myeloid leukemia (AML). This mutation has remarkable prognostic significance and correlates with distinct biological features. Our data from the sample-paired microRNA (miRNA) and mRNA microarrays of de novo AML patients strongly indicated that miRNA−mRNA regulation (MMR) may be dynamic and can be modulated by NPM1 mutation. We identified 493 NPM1 mutation-modulated MMR pairs by a systematic framework, in which MMR was attenuated specifically in patients carrying NPM1 mutations. The involved miRNAs/mRNAs were associated with cancer and hematological diseases, as well as known functions of NPM1 mutation including cell death and cellular response to therapeutics. The NPM1 mutation modulation could be validated with three approaches, including two independent cohort datasets, a high-throughput dataset derived from cell line-based experiments, and two in vitro models. Our study provides novel biological insights into the role of NPM1 mutation as a modulator of MMR, based on which novel prognostic markers are derived in AML.
Project description:Abstract Mutations in the gene encoding nucleophosmin (NPM1) carry prognostic value for patients with acute myeloid leukemia (AML). Various techniques are currently being used to detect these mutations in routine molecular diagnostics. Incorporation of accurate NPM1 mutation detection on a gene expression platform would enable simultaneous detection with various other expression biomarkers. Here we present an array based mutation detection using custom probes for NPM1 WT mRNA and NPM1 type A, B, and D mutant mRNA. This method was 100% accurate on a training cohort of 505 newly diagnosed unselected AML cases. Validation on an independent cohort of 143 normal karyotype AML cases revealed no false negative results, and one false positive (sensitivity 100.0%, and specificity 98.7%). Based on this, we conclude that this method provides a reliable method for NPM1 mutation detection. The method can be applied to other genes/mutations as long as the mutant alleles are sufficiently high expressed. Validation cohort of 143 AML cases analyzed using the AMLprofiler
Project description:Abstract Mutations in the gene encoding nucleophosmin (NPM1) carry prognostic value for patients with acute myeloid leukemia (AML). Various techniques are currently being used to detect these mutations in routine molecular diagnostics. Incorporation of accurate NPM1 mutation detection on a gene expression platform would enable simultaneous detection with various other expression biomarkers. Here we present an array based mutation detection using custom probes for NPM1 WT mRNA and NPM1 type A, B, and D mutant mRNA. This method was 100% accurate on a training cohort of 505 newly diagnosed unselected AML cases. Validation on an independent cohort of 143 normal karyotype AML cases revealed no false negative results, and one false positive (sensitivity 100.0%, and specificity 98.7%). Based on this, we conclude that this method provides a reliable method for NPM1 mutation detection. The method can be applied to other genes/mutations as long as the mutant alleles are sufficiently high expressed. Training cohort of 505 AML cases analyzed using the AMLprofiler
Project description:Adult de novo acute myeloid leukemia (AML) is a hematologic malignancy with poor prognosis, commonly driven by mutations in genes including the DNA methyltransferase DNMT3A and nucleophosmin NPM1. We previously generated sequentially inducible mouse models of these mutations and observed transformation from clonal hematopoiesis (CH) to myeloproliferative disorder to AML. In transformed AML, leukemia-propagating cells have a myeloid-restricted progenitor cell phenotype (c-Kit+). Here, to identify mechanisms that sustain tumorigenesis, we performed single-cell RNA-seq of c-Kit+ cells from four primary Dnmt3a;Npm1-mutant AML samples. The most primitive subset of c-Kit+ cells, a multipotent progenitor population Multi-Lin-2, had increased expression of the antioxidant and heavy metal chelator metallothionein 1 (Mt1) in all AML samples. Cas9-mediated Mt1 knockout in primary Dnmt3a;Npm1-mutant AML resulted in reduced cell cycling and proliferation and increased pyroptosis in vitro and increased overall survival following transplant into congenic recipient mice.