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Oligonucleotide Array CGH Profiles of Breast Cancer Patients Treated with High Dose or Conventional Chemotherapy

ABSTRACT: DNA copy number profiles can identify patients with a defect in BRCA1 or BRCA2. We previously showed that patients with a BRCA1 like profile benefit from intensified alkylating chemotherapy (IA, 4 cycles 5-fluorouracyl (5FU), epirubicin, cyclophosphamide (C) + 1 cycle carboplatin, thiotepa and cyclophosphamide with autologous stem cell transplantation (ASCT)). Presumably, this is because of the defect in error free homologous recombination DNA repair. Here we present an independent study IA chemotherapy (2 cycles induction, followed by ifosfamide, 12 g/m2; carboplatin, 900 mg/m2; and epirubicin, 180 mg/m2 with ASCT) versus anthracyclin-C (AC) or C-methothrexate-5FU (CMF) regimens in high risk breast cancer. DNA isolated from untreated resection specimens of 117 patients was labeled using Enzo labeling kit for array CGH and hybridized to a custom 135k Nimblegen platform.

ORGANISM(S): Homo sapiens

SUBMITTER: Philip Schouten

PROVIDER: E-GEOD-50407 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Breast cancers with a BRCA1-like DNA copy number profile recur less often than expected after high-dose alkylating chemotherapy.

Schouten Philip C PC Marmé Frederik F Aulmann Sebastian S Sinn Hans-Peter HP van Essen Hendrik F HF Ylstra Bauke B Hauptmann Michael M Schneeweiss Andreas A Linn Sabine C SC

Clinical cancer research : an official journal of the American Association for Cancer Research 20141205 4

<h4>Purpose</h4>Breast cancers in carriers of inactivating mutations of the BRCA1 gene carry a specific DNA copy-number signature ("BRCA1-like"). This signature is shared with cancers that inactivate BRCA1 through other mechanisms. Because BRCA1 is important in repair of DNA double-strand breaks through error-free homologous recombination, patients with a BRCA1-like tumor may benefit from high-dose alkylating (HD) chemotherapy, which induces DNA double-strand breaks.<h4>Experimental design</h4>W ...[more]

PMID: 25480832

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Dataset Information

Oligonucleotide Array CGH Profiles of Breast Cancer Patients Treated with High Dose or Conventional Chemotherapy

Publications

Breast cancers with a BRCA1-like DNA copy number profile recur less often than expected after high-dose alkylating chemotherapy.

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