Differential analysis of two-dimensional gel electrophoresis profile of pancreatic ductal adenocarcinoma and adjacent tissue

Objective To study the difference of expression of proteins in pancreatic cancer and adjacent fissue.Methods Proteomes of eight pairs of pancreatic ductal adenocarcinoma tissue samples and adjacent tissue samples were obtained by high resolution two-dimensional gel electrophoresis(2-DE).Comprehensive analyses of proteins were focused on total protein spots exhibiting statistical alternations between the two groups.Protein identification was done by peptide mass fingerprinting with tandem mass spectrometry(MS/MS).In addition,Western blotting and immunohistochemistry were performed to verify the expression of certain candidate protein.Results A total of 28 protein spot-features were found to be significantly increased and 17 significantly decreased in tumor tissues.Thirty of these protein spots were identified,which included enzymes,antioxidant proteins,signal transduction proteins,calcium-binding protein,structural proteins,chaperones and others.Western blotting and IHC further validated up-regulated expressions of one candidate protein(annexin II)in tumor tissues.Conclusions The analysis of proteomics with 2-DE on human tissue is a useful method for discovering valuable cancer marker candidates.These differential expressed proteins may serve as biomarkers for early detection and therapeutic targets to pancreatic cancer.