Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2006-1-4
pubmed:abstractText
Aberrant methylation of seven potential binding sites of the CTCF factor in the differentially methylated region upstream of the H19 gene (H19-DMR) has been suggested as critical for the regulation of IGF2 and H19 imprinted genes. In this study, we analyzed the allele-specific methylation pattern of CTCF binding sites 5 and 6 using methylation-sensitive restriction enzyme PCR followed by RFLP analysis in matched tumoral and lymphocyte DNA from head-and-neck squamous cell carcinoma (HNSCC) patients, as well as in lymphocyte DNA from control individuals who were cancer-free. The monoallelic methylation pattern was maintained in CTCF binding site 5 in 22 heterozygous out of 91 samples analyzed. Nevertheless, a biallelic methylation pattern was detected in CTCF binding site 6 in a subgroup of HNSCC patients as a somatic acquired feature of tumor cells. An atypical biallelic methylation was also observed in both tumor and lymphocyte DNA from two patients, and at a high frequency in the control group (29 out of 64 informative controls). Additionally, we found that the C/T transition detected by HhaI RFLP suppressed one dinucleotide CpG in critical CTCF binding site 6, of a mutation showing polymorphic frequencies. Although a heterogeneous methylation pattern was observed after DNA sequencing modified by sodium bisulfite, the biallelic methylation pattern was confirmed in 9 out of 10 HNSCCs. These findings are likely to be relevant in the epigenetic regulation of the DMR, especially in pathological conditions in which the imprinting of IGF2 and H19 genes is disrupted.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1107-3756
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
397-404
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:16391843-Adult, pubmed-meshheading:16391843-Aged, pubmed-meshheading:16391843-Aged, 80 and over, pubmed-meshheading:16391843-Alleles, pubmed-meshheading:16391843-Binding Sites, pubmed-meshheading:16391843-Case-Control Studies, pubmed-meshheading:16391843-DNA, pubmed-meshheading:16391843-DNA-Binding Proteins, pubmed-meshheading:16391843-Female, pubmed-meshheading:16391843-Genetic Heterogeneity, pubmed-meshheading:16391843-Genome, Human, pubmed-meshheading:16391843-Head and Neck Neoplasms, pubmed-meshheading:16391843-Heterozygote, pubmed-meshheading:16391843-Humans, pubmed-meshheading:16391843-Male, pubmed-meshheading:16391843-Methylation, pubmed-meshheading:16391843-Middle Aged, pubmed-meshheading:16391843-Pilot Projects, pubmed-meshheading:16391843-Polymorphism, Genetic, pubmed-meshheading:16391843-Protein Binding, pubmed-meshheading:16391843-Repressor Proteins, pubmed-meshheading:16391843-Sulfates
pubmed:year
2006
pubmed:articleTitle
H19-DMR allele-specific methylation analysis reveals epigenetic heterogeneity of CTCF binding site 6 but not of site 5 in head-and-neck carcinomas: a pilot case-control analysis.
pubmed:affiliation
Department of Genetics, Institute of Biosciences, Faculty of Medicine, UNESP -- Sao Paulo State University, Botucatu, SP 18618-000, Sao Paulo, Brazil.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't