Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
2005-10-5
pubmed:abstractText
Human Rad9 (hRad9), a structural homologue of yeast Schizosaccharomyces pombe rad9, is involved in cell cycle checkpoints and apoptosis. hRad9 can serve as a corepressor of androgen receptor in prostate cancer cells, but little is known about its role in the development of breast or other cancers. In the present study, semiquantitative reverse transcription-PCR showed that Rad9 mRNA levels were up-regulated in 52.1% (25 of 48) of breast tumors, and this up-regulation correlated with tumor size (P = 0.037) and local recurrence (P = 0.033). Overexpression of Rad9 mRNA was partly due to an increase in Rad9 gene number as measured by quantitative PCR. In other breast tumors with Rad9 mRNA overexpression but without increase in gene number, there was differential methylation of two putative Sp1/3 binding sites within the first and second introns of the Rad9 gene, which was similarly found in MCF-7 breast cancer cell line with increased Rad9 mRNA. Silencing Rad9 expression by RNA interference in MCF-7 cell line inhibited its proliferation in vitro. Promoter assays indicated that the Sp1/3 site in intron 2 may act as a silencer. In vivo binding of Sp3 to intron 2 was shown by chromatin immunoprecipitation assays. Treatment of MCF-7 cell line with 5'-aza-2'-deoxycytidine reduced Rad9 mRNA expression and also increased binding of Sp3 to the demethylated intron 2 region. Collectively, these findings suggest that Rad9 is a novel oncogene candidate activated by 11q13 amplification and DNA hypermethylation in breast cancer and may play a role in tumor proliferation and local invasion.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8646-54
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:16204032-Azacitidine, pubmed-meshheading:16204032-Base Sequence, pubmed-meshheading:16204032-Breast Neoplasms, pubmed-meshheading:16204032-Breast Neoplasms, Male, pubmed-meshheading:16204032-Cell Cycle Proteins, pubmed-meshheading:16204032-Cell Growth Processes, pubmed-meshheading:16204032-Cell Line, Tumor, pubmed-meshheading:16204032-Chromosomes, Human, Pair 11, pubmed-meshheading:16204032-Cyclin D1, pubmed-meshheading:16204032-DNA Methylation, pubmed-meshheading:16204032-Female, pubmed-meshheading:16204032-Gene Amplification, pubmed-meshheading:16204032-Gene Expression Regulation, Neoplastic, pubmed-meshheading:16204032-Gene Silencing, pubmed-meshheading:16204032-Humans, pubmed-meshheading:16204032-Introns, pubmed-meshheading:16204032-Male, pubmed-meshheading:16204032-Middle Aged, pubmed-meshheading:16204032-Molecular Sequence Data, pubmed-meshheading:16204032-RNA, Messenger
pubmed:year
2005
pubmed:articleTitle
The cell cycle checkpoint gene Rad9 is a novel oncogene activated by 11q13 amplification and DNA methylation in breast cancer.
pubmed:affiliation
University Department of Medicine, Queen Mary Hospital, Pokfulam, Hong Kong, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't