Gene Expression Profiling in Breast Cancer: Understanding the Molecular Basis of Histologic Grade To Improve Prognosis
SIB Swiss Institute of Bioinformatics · Université Libre de Bruxelles · +8 more institutions
Abstract
Histologic grade in breast cancer provides clinically important prognostic information. However, 30%–60% of tumors are classified as histologic grade 2. This grade is associated with an intermediate risk of recurrence and is thus not informative for clinical decision making. We examined whether histologic grade was associated with gene expression profiles of breast cancers and whether such profiles could be used to improve histologic grading.
We analyzed microarray data from 189 invasive breast carcinomas and from three published gene expression datasets from breast carcinomas. We identified differentially expressed genes in a training set of 64 estrogen receptor (ER)–positive tumor samples by comparing expression profiles between histologic grade 3 tumors and histologic grade 1 tumors and used the expression of these genes to define the gene expression grade index. Data from 597 independent tumors were used to evaluate the association between relapse-free survival and the gene expression grade index in a Kaplan–Meier analysis. All statistical tests were two-sided.
Citation impact
- FWCI
- 50.09
- Percentile
- 100%
- References
- 32
Authors
20- CSChristos SotiriouCorresponding
SIB Swiss Institute of Bioinformatics, Université Libre de Bruxelles, Karolinska University Hospital, Uppsala University Hospital, Cancer Research UK, John Radcliffe Hospital, The Netherlands Cancer Institute, University of Oxford, International Drug Development Institute (Belgium), Translational Research in Oncology
- PWPratyaksha Wirapati
SIB Swiss Institute of Bioinformatics, Université Libre de Bruxelles, Karolinska University Hospital, Uppsala University Hospital, Cancer Research UK, John Radcliffe Hospital, The Netherlands Cancer Institute, University of Oxford, International Drug Development Institute (Belgium), Translational Research in Oncology
- SLSherene Loi
SIB Swiss Institute of Bioinformatics, Université Libre de Bruxelles, Karolinska University Hospital, Uppsala University Hospital, Cancer Research UK, John Radcliffe Hospital, The Netherlands Cancer Institute, University of Oxford, International Drug Development Institute (Belgium), Translational Research in Oncology
- ALAdrian L. Harris
SIB Swiss Institute of Bioinformatics, Université Libre de Bruxelles, Karolinska University Hospital, Uppsala University Hospital, Cancer Research UK, John Radcliffe Hospital, The Netherlands Cancer Institute, University of Oxford, International Drug Development Institute (Belgium), Translational Research in Oncology
- SFSteve Fox
SIB Swiss Institute of Bioinformatics, Université Libre de Bruxelles, Karolinska University Hospital, Uppsala University Hospital, Cancer Research UK, John Radcliffe Hospital, The Netherlands Cancer Institute, University of Oxford, International Drug Development Institute (Belgium), Translational Research in Oncology
Topics & keywords
- Grading (engineering)
- Breast cancer
- Gene expression profiling
- Gene expression
- Medicine
- Pathology
- Proliferative index
- Oncology