DNA polymerase ε and δ exonuclease domain mutations in endometrial cancer.
Hum Mol Genet
; 22(14): 2820-8, 2013 Jul 15.
Article
en En
| MEDLINE
| ID: mdl-23528559
Accurate duplication of DNA prior to cell division is essential to suppress mutagenesis and tumour development. The high fidelity of eukaryotic DNA replication is due to a combination of accurate incorporation of nucleotides into the nascent DNA strand by DNA polymerases, the recognition and removal of mispaired nucleotides (proofreading) by the exonuclease activity of DNA polymerases δ and ε, and post-replication surveillance and repair of newly synthesized DNA by the mismatch repair (MMR) apparatus. While the contribution of defective MMR to neoplasia is well recognized, evidence that faulty DNA polymerase activity is important in cancer development has been limited. We have recently shown that germline POLE and POLD1 exonuclease domain mutations (EDMs) predispose to colorectal cancer (CRC) and, in the latter case, to endometrial cancer (EC). Somatic POLE mutations also occur in 5-10% of sporadic CRCs and underlie a hypermutator, microsatellite-stable molecular phenotype. We hypothesized that sporadic ECs might also acquire somatic POLE and/or POLD1 mutations. Here, we have found that missense POLE EDMs with good evidence of pathogenic effects are present in 7% of a set of 173 endometrial cancers, although POLD1 EDMs are uncommon. The POLE mutations localized to highly conserved residues and were strongly predicted to affect proofreading. Consistent with this, POLE-mutant tumours were hypermutated, with a high frequency of base substitutions, and an especially large relative excess of G:C>T:A transversions. All POLE EDM tumours were microsatellite stable, suggesting that defects in either DNA proofreading or MMR provide alternative mechanisms to achieve genomic instability and tumourigenesis.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Endometriales
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ADN Polimerasa II
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ADN Polimerasa III
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Mutación
Límite:
Adult
/
Aged
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Female
/
Humans
/
Middle aged
Idioma:
En
Revista:
Hum Mol Genet
Asunto de la revista:
BIOLOGIA MOLECULAR
/
GENETICA MEDICA
Año:
2013
Tipo del documento:
Article
Pais de publicación:
Reino Unido