Table of Contents
International Journal of Proteomics
Volume 2011, Article ID 628787, 13 pages
http://dx.doi.org/10.1155/2011/628787
Research Article

The Application of a Three-Step Proteome Analysis for Identification of New Biomarkers of Pancreatic Cancer

1Department of Molecular Diagnosis, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
2Clinical Proteomics Research Center, Chiba University Hospital, Chiba 260-8677, Japan
3Laboratory of Proteome Research, National Institute of Biomedical Innovation, Osaka 567-0085, Japan
4Laboratory of Biomolecular Dynamics, Department of Physics, Kitasato University School of Science, Sagamihara 252-0373, Japan
5Department of General Surgery, Graduate School of Medicine, Chiba University, 260-8670 Chiba, Japan

Received 31 May 2011; Accepted 2 August 2011

Academic Editor: Tadashi Kondo

Copyright © 2011 Mayinuer Abulaizi 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.

Abstract

We searched for novel tumor markers of pancreatic cancer by three-step serum proteome analysis. Twelve serum abundant proteins were depleted using immunoaffinity columns followed by fractionation by reverse-phase high-performance liquid chromatography. Proteins in each fraction were separated by two-dimensional gel electrophoresis. Then the gel was stained by Coomassie Brilliant Blue. Protein spots in which the expression levels were significantly different between cancer and normal control were identified by LC-MS/MS. One hundred and two spots were upregulated, and 84 spots were downregulated in serum samples obtained from patients with pancreatic cancers, and 58 proteins were identified by mass spectrometry. These candidate proteins were validated using western blot analysis and enzyme-linked immunosorbent assay (ELISA). As a result of these validation process, we could confirm that the serum levels of apolipoprotein A-IV, vitamin D-binding protein, plasma retinol-binding protein 4, and tetranectin were significantly decreased in patients with pancreatic cancer.