Quantitative Proteomic Analysis of Differentially Expressed Protein Profiles Involved in Pancreatic Ductal Adenocarcinoma.
OBJECTIVE
The aim of this study was to identify differentially expressed proteins among various stages of pancreatic ductal adenocarcinoma (PDAC) by shotgun proteomics using nano-liquid chromatography coupled tandem mass spectrometry and stable isotope dimethyl labeling.


METHODS
Differentially expressed proteins were identified and compared based on the mass spectral differences of their isotope-labeled peptide fragments generated from protease digestion.


RESULTS
Our quantitative proteomic analysis of the differentially expressed proteins with stable isotope (deuterium/hydrogen ratio, ≥ 2) identified a total of 353 proteins, with at least 5 protein biomarker proteins that were significantly differentially expressed between cancer and normal mice by at least a 2-fold alteration. These 5 protein biomarker candidates include α-enolase, α-catenin, 14-3-3 β, VDAC1, and calmodulin with high confidence levels. The expression levels were also found to be in agreement with those examined by Western blot and histochemical staining.


CONCLUSIONS
The systematic decrease or increase of these identified marker proteins may potentially reflect the morphological aberrations and diseased stages of pancreas carcinoma throughout progressive developments leading to PDAC. The results would form a firm foundation for future work concerning validation and clinical translation of some identified biomarkers into targeted diagnosis and therapy for various stages of PDAC.
From the *Division of Hepatobiliary Surgery, Department of Surgery, Kaohsiung Medical University Hospital, †Center for Stem Cell Research, ‡Graduate Institute of Medicine, College of Medicine, §Department of Biotechnology, College of Life Science, and ∥Center for Research Resources and Development, Kaohsiung Medical University, Kaohsiung, Taiwan; ¶Cell and Developmental Biology Program, Weill Graduate School of Medical Sciences, Cornell University, New York, NY; #Department of Pathology, Kaohsiung Municipal Hiao Kang Hospital; **Department of Radiology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University; ††Department of Medical Imaging, Kaohsiung Medical University Hospital; ‡‡Department of Genome Medicine, College of Medicine, Kaohsiung Medical University; §§Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung; ∥∥Institute of Biological Chemistry, Academia Sinica, Taipei; and ¶¶Center for Infectious Disease and Cancer Research, Kaohsiung Medical University, Kaohsiung, Taiwan.
Kung-Kai
KK
Kuo
Chao-Jen
CJ
Kuo
Chiang-Yen
CY
Chiu
Shih-Shin
SS
Liang
Chun-Hao
CH
Huang
Shu-Wen
SW
Chi
Kun-Bow
KB
Tsai
Chiao-Yun
CY
Chen
Edward
E
Hsi
Kuang-Hung
KH
Cheng
Shyh-Horng
SH
Chiou
D000818:Animals; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002853:Chromatography, Liquid; D019295:Computational Biology; D030562:Databases, Protein; D004195:Disease Models, Animal; D020022:Genetic Predisposition to Disease; D007553:Isotope Labeling; D051379:Mice; D008822:Mice, Transgenic; D036103:Nanotechnology; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D010449:Peptide Mapping; D010641:Phenotype; D060066:Protein Interaction Maps; D040901:Proteomics / Q000379:methods; D053719:Tandem Mass Spectrometry; D013997:Time Factors
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins