Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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IGR_Itzykson_CMML

ABSTRACT: Genomic studies in chronic myeloid malignancies, including myeloproliferative neoplasms (MPN), myelodysplastic syndromes (MDS) and MPN/MDS, have identified common mutations in genes encoding signaling, epigenetic, transcription and splicing factors. Analysis of 18 of these genes in a cohort of 224 chronic myelomonocytic leukemias (CMML), which is the most frequent MPN/MDS, identified at least one mutated gene in 95% of the patients, with some of the mutations affecting the disease phenotype. The number of mutated genes negatively affected progression-free and overall survival in multivariate analysis. Analysis of sorted progenitors indicated an early amplification of the CMML clone at the CD34+/CD38- stage of hematopoiesis, together with a premature granulomonocytic differentiation skewing. We interrogated the clone architecture by mutation-specific discrimination analysis of single-cell-derived colonies. The genetic classification of individual colonies allowed a designation of sub-clones and the assembly of putative evolutionary trees, indicating a linear acquisition of the studied mutations. Analysis of matched pre- and post-treatment samples demonstrated clonal persistence with limited and selective elimination of sub-clones. The disease was characterized by an amplification of multipotent and common myeloid progenitors in the CD34+ compartment, both fractions showing increased granulomonocytic differentiation at the expense of erythroid progenitors, contrasting with normal granulomonocytic progenitors. Altogether, early amplification of the leukemic clone and increased granulomonocytic differentiation of early progenitors may account for the specificity of CMML among myeloid neoplasms. This experiment correspond to the analysis of gene expression profiles in total CD34+ cells from the peripheral blood of 15 patients (Chronic Myelomonocytic Leukemia) and 4 healthy controls.

ORGANISM(S): Homo sapiens

SUBMITTER: Eric Solary

PROVIDER: E-MTAB-1044 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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IGR_Itzykson_CMML

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