Abstract |
Acquired platinum resistance is a serious problem in the treatment of ovarian carcinomas. However, the mechanism of the drug resistance has not been elucidated. Here, we show functional significance of restoration of BRCA2 protein by secondary BRCA2 mutations in acquired drug resistance of BRCA2-mutated ovarian carcinoma. Three ovarian cancer cell lines (PEO1, PEO4, and PEO6) were derived from a BRCA2 mutation [5193C>G (Y1655X)] carrier with ovarian carcinoma with acquired cisplatin resistance and a secondary BRCA2 mutation [5193C>T (Y1655Y)] that canceled the inherited mutation. PEO1 was BRCA2 deficient and sensitive to cisplatin and a poly(ADP-ribose) polymerase inhibitor, AG14361, whereas PEO4 was resistant. PEO4 and PEO6, derived from ascites at the time of relapse with cisplatin resistance, had the secondary mutation and were BRCA2 proficient. In vitro cisplatin/ AG14361 selection of PEO1 led to restoration of BRCA2 due to another secondary BRCA2 mutation. BRCA2 depletion sensitized BRCA2-restored PEO1 clones and PEO4 to cisplatin/ AG14361. Thus, restoration of BRCA2 due to secondary BRCA2 mutation is involved in acquired drug resistance of BRCA2-mutated ovarian carcinoma.
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Authors | Wataru Sakai, Elizabeth M Swisher, Céline Jacquemont, Kurapaty Venkatapoorna Chandramohan, Fergus J Couch, Simon P Langdon, Kaitlyn Wurz, Jake Higgins, Emily Villegas, Toshiyasu Taniguchi |
Journal | Cancer research
(Cancer Res)
Vol. 69
Issue 16
Pg. 6381-6
(Aug 15 2009)
ISSN: 1538-7445 [Electronic] United States |
PMID | 19654294
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
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Chemical References |
- Apoptosis Regulatory Proteins
- BLID protein, human
- BRCA2 Protein
- BRCA2 protein, human
- RNA, Small Interfering
- Cisplatin
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Topics |
- Apoptosis Regulatory Proteins
- BRCA2 Protein
(genetics, metabolism, physiology)
- Base Sequence
- Carcinoma
(genetics, metabolism)
- Cell Survival
(drug effects, genetics)
- Cisplatin
(pharmacology, therapeutic use)
- DNA Mutational Analysis
- Drug Resistance, Neoplasm
(genetics, physiology)
- Female
- Humans
- Mutation
(physiology)
- Open Reading Frames
(drug effects, genetics)
- Ovarian Neoplasms
(genetics, metabolism)
- RNA, Small Interfering
(pharmacology)
- Tumor Cells, Cultured
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