Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Genome-wide DNA methylation in MDS/secondary AML and de novo AML

ABSTRACT: An increasing body of work reveals aberrant hypermethylation of genes occurring in and potentially contributing to the pathogenesis of myeloid malignancies. Several of these diseases, such as myelodysplastic syndromes (MDS), are responsive to DNA methyltransferase inhibitors. In order to determine the extent of promoter hypermethylation in such tumors we compared the distribution of DNA methylation of 14,000 promoters in MDS and secondary AML patients enrolled in a phase I trial of 5-azacytidine and the histone deacetylase inhibitor entinostat against de novo AML patients and normal CD34+ bone marrow cells. The MDS and secondary AML patients displayed more extensive aberrant DNA methylation involving thousands of genes than did the normal CD34+ bone marrow cells or de novo AML blasts. Aberrant methylation in MDS and secondary AML tended to affect particular chromosomal regions, occurred more frequently in Alu poor genes, and included prominent involvement of genes involved in the WNT and MAPK signaling pathways. DNA methylation was also measured at days 15 and 29 after the first treatment cycle. DNA methylation was reversed at day 15 in a uniform manner throughout the genome, and this effect persisted through day 29, even without continuous administration of the study drugs. Keywords: DNA methylation profiling Direct comparison of DNA methylation in bone marrow samples from patients with Myelodysplastic syndrome or secondary Acute Myeloid Leukemia (AML) at baseline and after in vivo treatment with 5-azacytidine + etinostat. A comparison to de novo normal karyotype AML was also performed. Two control groups were included: one consisting of 8 CD34+ bone marrow samples from healthy donors and a second one consisting of matched CD34+ and CD34- fractions from the bone marrows of 4 healthy donors.

ORGANISM(S): Homo sapiens

SUBMITTER: Maria Figueroa

PROVIDER: E-GEOD-17328 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

MDS and secondary AML display unique patterns and abundance of aberrant DNA methylation.

Figueroa Maria E ME Skrabanek Lucy L Li Yushan Y Jiemjit Anchalee A Fandy Tamer E TE Paietta Elisabeth E Fernandez Hugo H Tallman Martin S MS Greally John M JM Carraway Hetty H Licht Jonathan D JD Gore Steven D SD Melnick Ari A

Blood 20090803 16

Increasing evidence shows aberrant hypermethylation of genes occurring in and potentially contributing to pathogenesis of myeloid malignancies. Several of these diseases, such as myelodysplastic syndromes (MDSs), are responsive to DNA methyltransferase inhibitors. To determine the extent of promoter hypermethylation in such tumors, we compared the distribution of DNA methylation of 14 000 promoters in MDS and secondary acute myeloid leukemia (AML) patients enrolled in a phase 1 trial of 5-azacyt ...[more]

PMID: 19652201

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Dataset Information

Genome-wide DNA methylation in MDS/secondary AML and de novo AML

Publications

MDS and secondary AML display unique patterns and abundance of aberrant DNA methylation.

Similar Datasets

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