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: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:Background: MicroRNAs are regulators of gene expression, mainly functioning by decreasing mRNA levels of their multiple targets. Deregulated microRNA expression has been shown for acute myeloid leukemia, a disease also characterized by altered gene expression associated with distinct genomic aberrations such as nucleophosmin (NPM1) mutations. To further illuminate the role of deregulated microRNA and gene expression in cytogenetically normal acute myeloid leukemia with NPM1 mutation, we performed an integrative analysis of microRNA and mRNA expression data sets. Design and Methods: Both microRNA and gene expression profiles were measured in a cohort of 43 adult acute myeloid leukemia patient samples (n=42 cytogenetically normal, n=1 del7q; median age 46 years [range 23-60]) of known NPM1 mutation status (n=23 mutated, n=20 wild-type) and data integratively analyzed. Putative microRNA-mRNA interactions were validated by quantitative RT-PCR, Western Blot and luciferase reporter assays. For selected microRNAs, sensitivity of microRNA-overexpressing cells to cytarabine treatment was tested by FACS viability and cell proliferation assays. Results: Our integrative approach of analyzing both microRNA and gene expression profiles in parallel resulted in a refined list of putative target genes affected by NPM1 mutation-associated microRNA deregulation. Of 177 putative microRNA - target mRNA interactions, we could identify and validate 77 novel candidates with known or potential implication in leukemogenesis, such as IRF2-miR-20a, KIT-miR-20a and MN1-miR-15a. Furthermore, our data showed that deregulated expression of tumor suppressor microRNAs such as miR-29a and miR-30c might contribute to the sensitivity to cytarabine, which is observed in NPM1-mutated acute myeloid leukemia. Conclusions: Overall, our observations highlight that integrative data analysis approaches can improve insights into leukemia biology, and lead to the identification of novel microRNA - target gene interactions of potential relevance for acute myeloid leukemia treatment. MicroRNA and gene expression profiles were measured in a cohort of 43 adult (42 cytogenetically normal and 1 del7q) acute myeloid leukemia patient samples of known NPM1 mutation status (n=23 mutated, n=20 wild-type). This submission represents the mRNA expression component of the study. The miRNA expression data will be deposited as supplementary information along with the accompanying manuscript.
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:Acute myeloid leukemia (AML) carrying NPM1 mutations and cytoplasmic nucleophosmin (NPMc+ AML) accounts for about one-third of adult AML and shows distinct features, including a unique gene expression profile. MicroRNAs (miRNAs) are small noncoding RNAs of 19-25 nucleotides in length that have been linked to the development of cancer. Here, we investigated the role of miRNAs in the biology of NPMc+ AML. The miRNA expression was evaluated in 85 adult de novo AML patients characterized for subcellular localization/mutation status of NPM1 and FLT3 mutations using a custom microarray platform. Data were analyzed by using univariate t test within BRB tools. We identified a strong miRNA signature that distinguishes NPMc+ mutated (n = 55) from the cytoplasmic-negative (NPM1 unmutated) cases (n = 30) and includes the up-regulation of miR-10a, miR-10b, several let-7 and miR-29 family members. Many of the down-regulated miRNAs including miR-204 and miR-128a are predicted to target several HOX genes. Indeed, we confirmed that miR-204 targets HOXA10 and MEIS1, suggesting that the HOX up-regulation observed in NPMc+ AML may be due in part by loss of HOX regulators-miRNAs. FLT3-ITD+ samples were characterized by up-regulation of miR-155. Further experiments demonstrated that the up-regulation of miR-155 was independent from FLT3 signaling. Our results identify a unique miRNA signature associated with NPMc+ AML and provide evidence that support a role for miRNAs in the regulation of HOX genes in this leukemia subtype. Moreover, we found that miR-155 was strongly but independently associated with FLT3-ITD mutations.