RESUMO
Myeloproliferative neoplasms (MPNs) feature a malignant clone containing the JAK2 V617F mutation, or another mutation causing dysregulated JAK2 kinase activity. The multiple disease phenotypes of MPNs, and their tendency to transform phenotypically, suggest pathophysiologic heterogeneities beyond a common phenomenon of JAK2 hyperactivation. JAK2 has the potential to activate multiple other signaling molecules, either directly through downstream effectors, or indirectly through induction of target gene expression. We have interrogated myeloproliferative signaling in myelofibrosis (MF) and secondary acute myeloid leukemia (sAML) patient samples using mass cytometry, which allows the quantitative measurement of multiple signaling molecules simultaneously at the single-cell level, in cell populations representing a nearly complete spectrum of hematopoiesis. MF and sAML malignant cells demonstrated a high prevalence of hyperactivation of the JAK-STAT, MAP kinase, PI3 kinase and NFκB signaling pathways. Constitutive NFκB signaling was evident across MF and sAML patients. A supporting gene set enrichment analysis (GSEA) of MF showed many NFκB target genes to be expressed above normal levels in MF patient CD34+ cells. NFκB inhibition suppressed colony formation from MF CD34+ cells. This study indicates that NFκB signaling contributes to human myeloproliferative disease and is abnormally activated in MF and sAML.
Assuntos
Leucemia Mieloide Aguda/metabolismo , NF-kappa B/metabolismo , Mielofibrose Primária/metabolismo , Transdução de Sinais , Antígenos CD34 , Medula Óssea , Linhagem Celular , Citometria de Fluxo/métodos , Humanos , Janus Quinase 2/genética , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/patologia , Mielofibrose Primária/patologiaAssuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Policitemia Vera/tratamento farmacológico , Dasatinibe/administração & dosagem , Feminino , Proteínas de Fusão bcr-abl/genética , Humanos , Janus Quinase 2/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/complicações , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Pessoa de Meia-Idade , Nitrilas , Policitemia Vera/complicações , Policitemia Vera/genética , Pirazóis/administração & dosagem , PirimidinasRESUMO
Clonal architecture in myeloproliferative neoplasms (MPNs) is poorly understood. Here we report genomic analyses of a patient with primary myelofibrosis (PMF) transformed to secondary acute myeloid leukemia (sAML). Whole genome sequencing (WGS) was performed on PMF and sAML diagnosis samples, with skin included as a germline surrogate. Deep sequencing validation was performed on the WGS samples and an additional sample obtained during sAML remission/relapsed PMF. Clustering analysis of 649 validated somatic single-nucleotide variants revealed four distinct clonal groups, each including putative driver mutations. The first group (including JAK2 and U2AF1), representing the founding clone, included mutations with high frequency at all three disease stages. The second clonal group (including MYB) was present only in PMF, suggesting the presence of a clone that was dispensable for transformation. The third group (including ASXL1) contained mutations with low frequency in PMF and high frequency in subsequent samples, indicating evolution of the dominant clone with disease progression. The fourth clonal group (including IDH1 and RUNX1) was acquired at sAML transformation and was predominantly absent at sAML remission/relapsed PMF. Taken together, these findings illustrate the complex clonal dynamics associated with disease evolution in MPNs and sAML.
