Protein lysate microarray analysis of uPA and PAI-1 from formalin-fixed breast cancers

Coordinator:		Prof. Dr. Karl-Friedrich Becker
Institution:		Institut für Pathologie der Technischen Universität München
Homepage:		www.path.med.tu-muenchen.de/

Two markers with extraordinary clinical relevance are the urokinase-type plasminogen activator (uPA) and its inhibitor, PAI-1. Both proteins play a key role in tumour invasion and metastasis. Node-negative breast cancer patients with low levels of uPA and PAI-1 in their primary tumours have a very good prognosis; thus, for these patients the burden of adjuvant chemotherapy may be spared. Unfortunately, the method of choice to determine both markers in tissues is by an immunometric assay (ELISA) with the need for fresh or frozen tissues, thus preventing application of both markers in many hospitals. The aim of this subproject is to analyse for the first time both markers in routinely formalin-fixed tissues using protein lysate microarrays; the methodology needed has been established recently. We will determine the abundances of uPA and PAI-1, compare the measurements with ELISA data obtained in parallel and correlate the results with disease free survival and overall survival. We will define standards for the analysis of uPA and PAI-1 for routine use of both markers in many hospitals around the world.