gms | German Medical Science

27th German Cancer Congress Berlin 2006

German Cancer Society (Frankfurt/M.)

22. - 26.03.2006, Berlin

Breast cancer proteomics by laser capture microdissection, sample pooling, 54 cm immobilised pH gradient isoelectric focussing, and differential iodine radioisotope detection

Meeting Abstract

  • corresponding author presenting/speaker Hans Neubauer - University Women's Hospital, Tuebingen, Germany, Deutschland
  • Susan Clare - University Women´s Hospital, Tuebingen, Germany
  • Raffael Kurek - University Women's Hospital, Tuebingen, Germany
  • Tanja Fehm - University Women's Hospital, Tuebingen, Germany
  • Karl Sotlar - Department of Pathology, University of Tuebingen, Germany
  • Alfred Nordheim - Department of Molecular Biology and Proteome Center, Institute for Cell Biology, University of Tuebingen, Germany
  • André Schrattenholz - ProteoSys AG, Carl-Zeiss-Str. 51, 55129 Mainz, Germany
  • Michael Cahill - ProteoSys AG, Carl-Zeiss-Str. 51, 55129 Mainz, Germany
  • Diethelm Wallwiener - University Women's Hospital, Tuebingen, Germany
  • Erich Solomayer - University Women's Hospital, Tuebingen, Germany

27. Deutscher Krebskongress. Berlin, 22.-26.03.2006. Düsseldorf, Köln: German Medical Science; 2006. DocOP062

The electronic version of this article is the complete one and can be found online at:

Published: March 20, 2006

© 2006 Neubauer et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



The presence of progesterone receptor (PR) in estrogen receptor (ER)-positive breast cancer indicates that tumors are likely to respond to tamoxifen. In order to reveal the potential molecular mechanism of this phenomenon we sought to identify differential protein abundances between invasive ductal carcinoma cells from cryopreserved ER+/PR+ and ER+/PR- mammary tumor specimens. Because current proteomics methods are hampered in the examination of most primary human tumor samples by extreme tissue heterogeneity we used laser capture microdissection (LCM) to isolate tumor cells and developed a sample pooling strategy to analyse small sample protein lysates. Proteins from LCM-harvested tumors were pooled into 4 sub-pools from each condition of 3 tumors/sub-pool, and proteins from respective paired sub-pools were co-electrophoresed by 2-DE using 54 cm IEF over pH 4-9. Abundance ratios were accurately quantified by differential multiplex radioactive ProteoTope method at low attomole level (≈3.6 μg protein per labeling reaction, <180 ng per multiplex protein sample per 54 cm gel). Applying this approach, differentially displayed proteins were identified by mass spectrometry using co-migrating nonradioactively labelled tumor proteins. They include decreased cytochrome b5 and transgelin, and more abundant CRABP-II, cyclophilin A, Neudesin, and hemoglobin in ER+/PR+ tumors versus ER+/PR- providing a possible explanation for differential susceptibility against tamoxifen as a result of deregulated cytochrome b5-dependent metabolism. This study demonstrates the potential of ProteoTope and LCM to enable extremely sensitive and precise differential analyses from well defined primary