Table of Contents
ISRN Oncology
Volume 2012, Article ID 450267, 12 pages
Research Article

Molecular Profiles of Pre- and Postoperative Breast Cancer Tumours Reveal Differentially Expressed Genes

1Department of Surgery, Akershus University Hospital, 1478 Lørenskog, Norway
2Institute for Clinical Medicine, Faculty of Medicine, University of Oslo, 0318 Oslo, Norway
3Department of Clinical Molecular Biology and Laboratory Sciences (EpiGen), Akershus University Hospital, 1478 Lørenskog, Norway
4The Simons Center for Systems Biology, Institute for Advanced Study, Princeton, NJ 08540, USA
5Department of Genetics, Institute for Cancer Research, Oslo University Hospital Radiumhospitalet, 0310 Oslo, Norway
6Department of Pathology, Akershus University Hospital, 1478 Lørenskog, Norway
7Institute of Health Promotion, Akershus University Hospital, 1478 Lørenskog, Norway

Received 31 August 2012; Accepted 18 October 2012

Academic Editors: E. A. Rakha and S. Ran

Copyright © 2012 Margit L. H. Riis et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Gene expression studies on breast cancer have generally been performed on tissue obtained at the time of surgery. In this study, we have compared the gene expression profiles in preoperative tissue (core needle biopsies) while tumor is still in its normal milieu to postoperative tissue from the same tumor obtained during surgery. Thirteen patients were included of which eleven had undergone sentinel node diagnosis procedure before operation. Microarray gene expression analysis was performed using total RNA from all the samples. Paired significance analysis of microarrays revealed 228 differently expressed genes, including several early response stress-related genes such as members of the fos and jun families as well as genes of which the expression has previously been associated with cancer. The expression profiles found in the analyses of breast cancer tissue must be evaluated with caution. Different profiles may simply be the result of differences in the surgical trauma and timing of when samples are taken and not necessarily associated with tumor biology.