Linked Life Data

12393509

Source:http://linkedlifedata.com/resource/pubmed/id/12393509

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2003-1-31
pubmed:abstractText
Children with Down syndrome (DS) with acute myeloid leukemia (AML) have significantly higher event-free survival rates compared to those with non-DS AML, linked to greater cytosine arabinoside (ara-C) sensitivity and higher transcript levels of the chromosome 21-localized gene, cystathionine-beta-synthase (CBS), in DS myeloblasts. In this study, we examined the transcriptional regulation of the CBS gene in the DS megakaryocytic leukemia (AMkL) cell line, CMK, characterized by significantly higher CBS transcripts compared with the non-DS AMkL cell line, CMS. Rapid amplification of 5'-cDNA ends (5'-RACE) analysis demonstrated exclusive use of the CBS -1b promoter in the cell lines, and transient transfections with the full-length CBS -1b luciferase reporter gene construct showed 40-fold greater promoter activity in the CMK than CMS cells. Electrophoretic mobility shift assays showed enhanced binding of the transcription factors Sp1/Sp3 to 2 GC/GT-box elements (GC-f and GT-d) in the upstream regions of the CBS -1b promoter in CMK nuclear extracts and undetectable binding in CMS cells. Mutation of the GC-f- or GT-d-binding site resulted in an approximately 90% decrease of the CBS -1b promoter activity in transient transfections of CMK cells. Chromatin immunoprecipitation assays confirmed in vivo binding of Sp3, USF-1, and nuclear factor YA (NF-YA) to the CBS -1b promoter region in chromatin extracts of CMK and CMS cells. Decreased binding of Sp1/Sp3 in CMK nuclear extracts following treatment with calf alkaline phosphatase suggested a role for phosphorylation of Sp1/Sp3 in regulating CBS promoter activity and in the differential CBS expression between CMK and CMS cells. The results of this study with clinically relevant cell line models suggest potential mechanisms for disparate patterns of CBS gene expression in DS and non-DS myeloblasts and may, in part, explain the greater sensitivity to chemotherapy shown by patients with DS AML.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
101
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1551-7
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:12393509-Cystathionine beta-Synthase, pubmed-meshheading:12393509-Cytarabine, pubmed-meshheading:12393509-DNA, pubmed-meshheading:12393509-DNA-Binding Proteins, pubmed-meshheading:12393509-Down Syndrome, pubmed-meshheading:12393509-Gene Expression Regulation, Enzymologic, pubmed-meshheading:12393509-Humans, pubmed-meshheading:12393509-Leukemia, Megakaryoblastic, Acute, pubmed-meshheading:12393509-Luciferases, pubmed-meshheading:12393509-Mutagenesis, Site-Directed, pubmed-meshheading:12393509-Phosphorylation, pubmed-meshheading:12393509-Promoter Regions, Genetic, pubmed-meshheading:12393509-Sp1 Transcription Factor, pubmed-meshheading:12393509-Sp3 Transcription Factor, pubmed-meshheading:12393509-Transcription, Genetic, pubmed-meshheading:12393509-Transcription Factors, pubmed-meshheading:12393509-Transfection, pubmed-meshheading:12393509-Tumor Cells, Cultured
pubmed:year
2003
pubmed:articleTitle
Transcriptional regulation of the cystathionine-beta -synthase gene in Down syndrome and non-Down syndrome megakaryocytic leukemia cell lines.
pubmed:affiliation
Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Division of Pediatric Hematology/Oncology, Children's Hospital of Michigan, Detroit, MI 48201, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't