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Genome-wide DNA methylation profiling predicts relapse in childhood B-cell acute lymphoblastic leukemia

ABSTRACT: Although the 5-year survival of childhood Acute Lymphoblastic Leukemia (ALL) exceeds 80%, a group of patients presents poor prognosis due to early relapse. To date, treatment strategies are defined by cytogenetically-based subtype categorization. However, ALL patients without chromosomal translocations associated with poor prognosis lack diagnostic markers to adjust specific therapies. DNA methylation alteration is a frequent event in cancer with high potential in diagnosis, prognosis and prediction of drug response. Hence, we aimed to characterize childhood B-ALLs without Philadelphia (BCR-ABL) and MLL translocations based on their DNA methylation profile of more than 450,000 CpG sites to improve accuracy in prognosis and treatment strategies. DNA was quantified by Quant-iT PicoGreen dsDNA Reagent (Invitrogen) and the integrity was analyzed in a 1.3% agarose gel. Bisulfite conversion of 600 ng of each sample was performed according to the manufacturer's recommendation for the Illumina Infinium Assay. Effective bisulfite conversion was checked for three controls that were converted simultaneously with the samples. 4 ul of bisulfite-converted DNA were used to hybridize on Infinium HumanMethylation 450 BeadChip, following the Illumina Infinium HD Methylation protocol. Chip analysis was performed using the Illumina HiScan SQ fluorescent scanner. The intensities of the images were extracted using GenomeStudio (2010.3) Methylation module (1.8.5) software. The methylation score of each CpG is represented as a beta value.

ORGANISM(S): Homo sapiens

SUBMITTER: Antonio Gómez

PROVIDER: E-GEOD-39141 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Genome-wide DNA methylation profiling predicts relapse in childhood B-cell acute lymphoblastic leukaemia.

Sandoval Juan J Heyn Holger H Méndez-González Jesús J Gomez Antonio A Moran Sebastian S Baiget Montserrat M Melo Montserrat M Badell Isabel I Nomdedéu Josep F JF Esteller Manel M

British journal of haematology 20121030 3

PMID: 23110451

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