Urinary Proteomic Biomarkers in Coronary Artery Disease

• DOI: 10.1074/mcp.m700394-mcp200
• Publication Date: 2007-10-19T23:33:24Z
• Authors: Lukas U. Zimmerli; Eric Schiffer; Petra Zürbig; David M. Good; Markus Kellmann; Laetitia Mouls; Andrew R. Pitt; Joshua J. Coon; Roland E. Schmieder; Karlheinz H. Peter; Harald Mischak; Walter Kolch; Christian Delles; Anna F. Dominiczak
• Keywords: Male; 0301 basic medicine; 1602 Analytical Chemistry; 1303 Biochemistry; Proteome; Molecular Sequence Data; 610 Medicine & health; Coronary Artery Disease; Middle Aged; Mass Spectrometry; Body Mass Index; 3. Good health; 03 medical and health sciences; ROC Curve; Case-Control Studies; 1312 Molecular Biology; Humans; Female; Amino Acid Sequence; 10029 Clinic and Policlinic for Internal Medicine; Peptides; Biomarkers

Urinary proteomics is emerging as a powerful non-invasive tool for diagnosis and monitoring of variety of human diseases. We tested whether signatures of urinary polypeptides can contribute to the existing biomarkers for coronary artery disease (CAD). We examined a total of 359 urine samples from 88 patients with severe CAD and 282 controls. Spot urine was analyzed using capillary electrophoresis on-line coupled to ESI-TOF-MS enabling characterization of more than 1000 polypeptides per sample. In a first step a "training set" for biomarker definition was created. Multiple biomarker patterns clearly distinguished healthy controls from CAD patients, and we extracted 15 peptides that define a characteristic CAD signature panel. In a second step, the ability of the CAD-specific panel to predict the presence of CAD was evaluated in a blinded study using a "test set." The signature panel showed sensitivity of 98% (95% confidence interval, 88.7-99.6) and 83% specificity (95% confidence interval, 51.6-97.4). Furthermore the peptide pattern significantly changed toward the healthy signature correlating with the level of physical activity after therapeutic intervention. Our results show that urinary proteomics can identify CAD patients with high confidence and might also play a role in monitoring the effects of therapeutic interventions. The workflow is amenable to clinical routine testing suggesting that non-invasive proteomics analysis can become a valuable addition to other biomarkers used in cardiovascular risk assessment.