Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
2000-3-9
pubmed:abstractText
Women heterozygous for mutations in the breast-cancer susceptibility genes BRCA1 and BRCA2 have a highly elevated risk of developing breast cancer [1]. BRCA1 and BRCA2 encode large proteins with no sequence similarity to one another. Although involvement in DNA repair and transcription has been suggested, it is still not understood how loss of function of these genes leads to breast cancer [2]. Embryonic fibroblasts (MEFs) derived from mice homozygous for a hypomorphic mutation (Brca2(Tr2014)) within the 3' region of exon 11 in Brca2 [3], or a similar mutation (Brca2(Tr)) [4], proliferate poorly in culture and overexpress the tumour suppressor p53 and the cyclin-dependent kinase inhibitor p21(Waf1/Cip1). These MEFs have intact p53-dependent DNA damage G(1)-S [3] [4] and G(2)-M checkpoints [4], but are impaired in DNA double-strand break repair [3] and develop chromosome aberrations [4]. Here, we report that Brca2(Tr2014/Tr2014) MEFs frequently develop micronuclei. These abnormal DNA-containing bodies were formed through both loss of acentric chromosome fragments and by chromosome missegregation, which resulted in aneuploidy. Absence of Brca2 also led to centrosome amplification, which we found associated with the formation of micronuclei. These data suggest a potential mechanism whereby loss of BRCA2 may, within subclones, drive the loss of cell-cycle regulation genes, enabling proliferation and tumourigenesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0960-9822
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1107-10
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10531007-Aneuploidy, pubmed-meshheading:10531007-Animals, pubmed-meshheading:10531007-BRCA2 Protein, pubmed-meshheading:10531007-Cells, Cultured, pubmed-meshheading:10531007-Centrosome, pubmed-meshheading:10531007-Chromosome Breakage, pubmed-meshheading:10531007-DNA, Satellite, pubmed-meshheading:10531007-Epithelial Cells, pubmed-meshheading:10531007-Exons, pubmed-meshheading:10531007-Fluorescein-5-isothiocyanate, pubmed-meshheading:10531007-Gene Amplification, pubmed-meshheading:10531007-Gene Expression Regulation, Neoplastic, pubmed-meshheading:10531007-Genome, pubmed-meshheading:10531007-Humans, pubmed-meshheading:10531007-Mice, pubmed-meshheading:10531007-Micronuclei, Chromosome-Defective, pubmed-meshheading:10531007-Mitosis, pubmed-meshheading:10531007-Mutation, pubmed-meshheading:10531007-Neoplasm Proteins, pubmed-meshheading:10531007-Time Factors, pubmed-meshheading:10531007-Transcription Factors
pubmed:year
1999
pubmed:articleTitle
Absence of Brca2 causes genome instability by chromosome breakage and loss associated with centrosome amplification.
pubmed:affiliation
Section of Gene Function and Regulation Chester Beatty Laboratories Institute of Cancer Research 237 Fulham Road, London, SW3 6JB, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't