title: Proteomic identification of serum biomarkers for gastric cancer using multi-dimensional liquid chromatography and 2D differential gel electrophoresis.
abstract: BACKGROUND
  Early diagnosis and treatment of gastric cancer patients is essential for improving prognosis. However, no available serum-based test provides sufficient sensitivity or specificity for widespread use. Therefore, in this study we aimed to identify cancer biomarkers in human sera using 2-dimensional difference gel electrophoresis (2D-DIGE), and to characterize protein biomarkers with tandem mass spectrometry.
  
  
  METHODS
  We compared the serum proteomic profiles of 20 gastric cancer patients and 10 healthy volunteers. Serum samples were first chromatographed using an immunoaffinity high-performance liquid chromatography (HPLC) column to selectively remove albumin, immunoglobulins, transferrin, haptoglobin, and antitrypsin. Differential protein analysis was then performed using DIGE. Significantly increased and decreased protein spot features were excised, trypsin digested, and analyzed by tandem matrix-assisted laser desorption/ionization (MALDI) time of flight (TOF)/TOF and a linear trap quadrupole (LTQ) mass spectrometer.
  
  
  RESULTS
  Seventeen protein spot features were significantly increased and 7 were significantly decreased in cancer serum samples compared to healthy controls. We identified 7 unique proteins that were upregulated, including plasminogen, apolipoprotein A-IV, Kininogen-1, complex-forming glycoprotein HC, complement component C4A, apolipoprotein J, and clusterin, and 5 that were decreased.
  
  
  CONCLUSIONS
  These results suggest that the combination of multi-dimensional HPLC and 2D-DIGE provides a valuable tool for serum proteomics in gastric cancer.
authors.affiliation: Key Laboratory of Shanghai Gastric Neoplasms, Department of Surgery, Ruijin Hospital, Shanghai Jiao Tong University, Shanghai 200025, PR China.
authors.forename: Wentao
authors.initials: W
authors.lastname: Liu
authors.forename: Bingya
authors.initials: B
authors.lastname: Liu
authors.forename: Qu
authors.initials: Q
authors.lastname: Cai
authors.forename: Jianfang
authors.initials: J
authors.lastname: Li
authors.forename: Xuehua
authors.initials: X
authors.lastname: Chen
authors.forename: Zhenggang
authors.initials: Z
authors.lastname: Zhu
mesh_terms: D000328:Adult; D000368:Aged; D000418:Albumins / Q000032:analysis; D014408:Biomarkers, Tumor / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D006242:Haptoglobins / Q000032:analysis; D006801:Humans; D007136:Immunoglobulins / Q000097:blood; D008297:Male; D008875:Middle Aged; D040901:Proteomics; D013274:Stomach Neoplasms / Q000097:blood* / Q000175:diagnosis; D014168:Transferrin / Q000032:analysis; D000515:alpha 1-Antitrypsin / Q000097:blood
chemical_list: D000418:Albumins; D014408:Biomarkers, Tumor; D006242:Haptoglobins; D007136:Immunoglobulins; D014168:Transferrin; D000515:alpha 1-Antitrypsin