Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

The gene expression signature of genomic instability in breast cancer is an independent predictor of clinical outcome

ABSTRACT: Recently, expression profiling of breast carcinomas has revealed gene signatures that predict clinical outcome, and discerned prognostically relevant breast cancer subtypes. Measurement of the degree of genomic instability provides a very similar stratification of prognostic groups. We therefore hypothesized that these features are linked. We used gene expression profiling of 48 breast cancer specimens that profoundly differed in their degree of genomic instability and identified a set of 12 genes that defines the two groups. The biological and prognostic significance of this gene set was established through survival prediction in published datasets from patients with breast cancer. Of note, the gene expression signatures that define specific prognostic subtypes in other breast cancer datasets predicted genomic instability in our samples. This remarkable congruence suggests a biological dependency of poor-prognosis gene signatures, breast cancer subtypes, genomic instability, and clinical outcome. Keywords: disease state analysis 44 samples

ORGANISM(S): Homo sapiens

SUBMITTER: Jens Habermann

PROVIDER: E-GEOD-11901 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Chromosomal instability determines taxane response.

Swanton Charles C Nicke Barbara B Schuett Marion M Eklund Aron C AC Ng Charlotte C Li Qiyuan Q Hardcastle Thomas T Lee Alvin A Roy Rajat R East Philip P Kschischo Maik M Endesfelder David D Wylie Paul P Kim Se Nyun SN Chen Jie-Guang JG Howell Michael M Ried Thomas T Habermann Jens K JK Auer Gert G Brenton James D JD Szallasi Zoltan Z Downward Julian J

Proceedings of the National Academy of Sciences of the United States of America 20090519 21

Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells. Ov ...[more]

PMID: 19458043

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Dataset Information

The gene expression signature of genomic instability in breast cancer is an independent predictor of clinical outcome

Publications

Chromosomal instability determines taxane response.

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