Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
2010-10-8
pubmed:abstractText
In Burkitt lymphoma/leukemia (BL), achievement of complete remission with first-line chemotherapy remains a challenging issue, as most patients who respond remain disease-free, whereas those refractory have few options of being rescued with salvage therapies. The mechanisms underlying BL chemoresistance and how it can be circumvented remain undetermined. We previously reported the frequent inactivation of the proapoptotic BIM gene in B-cell lymphomas. Here we show that BIM epigenetic silencing by concurrent promoter hypermethylation and deacetylation occurs frequently in primary BL samples and BL-derived cell lines. Remarkably, patients with BL with hypermethylated BIM presented lower complete remission rate (24% vs 79%; P = .002) and shorter overall survival (P = .007) than those with BIM-expressing lymphomas, indicating that BIM transcriptional repression may mediate tumor chemoresistance. Accordingly, by combining in vitro and in vivo studies of human BL-xenografts grown in immunodeficient RAG2(-/-)?c(-/-) mice and of murine B220(+)IgM(+) B-cell lymphomas generated in E?-MYC and E?-MYC-BIM(+/-) transgenes, we demonstrate that lymphoma chemoresistance is dictated by BIM gene dosage and is reversible on BIM reactivation by genetic manipulation or after treatment with histone-deacetylase inhibitors. We suggest that the combination of histone-deacetylase inhibitors and high-dose chemotherapy may overcome chemoresistance, achieve durable remission, and improve survival of patients with BL.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1528-0020
pubmed:author
pubmed:issnType
Electronic
pubmed:day
7
pubmed:volume
116
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2531-42
pubmed:meshHeading
pubmed-meshheading:20570860-Animals, pubmed-meshheading:20570860-Antibiotics, Antineoplastic, pubmed-meshheading:20570860-Apoptosis Regulatory Proteins, pubmed-meshheading:20570860-Burkitt Lymphoma, pubmed-meshheading:20570860-Cell Line, Tumor, pubmed-meshheading:20570860-Doxorubicin, pubmed-meshheading:20570860-Drug Resistance, Neoplasm, pubmed-meshheading:20570860-Gene Expression Regulation, Neoplastic, pubmed-meshheading:20570860-Gene Silencing, pubmed-meshheading:20570860-Histone Deacetylase Inhibitors, pubmed-meshheading:20570860-Humans, pubmed-meshheading:20570860-Membrane Proteins, pubmed-meshheading:20570860-Mice, pubmed-meshheading:20570860-Mice, Inbred C57BL, pubmed-meshheading:20570860-Mice, Knockout, pubmed-meshheading:20570860-Mice, Transgenic, pubmed-meshheading:20570860-Promoter Regions, Genetic, pubmed-meshheading:20570860-Proto-Oncogene Proteins, pubmed-meshheading:20570860-Proto-Oncogene Proteins c-myc, pubmed-meshheading:20570860-Tumor Cells, Cultured
pubmed:year
2010
pubmed:articleTitle
Reversion of epigenetically mediated BIM silencing overcomes chemoresistance in Burkitt lymphoma.
pubmed:affiliation
Division of Oncology, Center for Applied Medical Research, University of Navarra, Pamplona, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't