title: Proteomic analysis of gastric cancer and immunoblot validation of potential biomarkers.
abstract: OBJECTIVE
  To search for and validate differentially expressed proteins in patients with gastric adenocarcinoma.
  
  
  METHODS
  We used two-dimensional gel electrophoresis and mass spectrometry to search for differentially expressed proteins in patients with gastric adenocarcinoma. A set of proteins was validated with immunoblotting.
  
  
  RESULTS
  We identified 30 different proteins involved in various biological processes: metabolism, development, death, response to stress, cell cycle, cell communication, transport, and cell motility. Eight proteins were chosen for further validation by immunoblotting. Our results show that gastrokine-1, 39S ribosomal protein L12 (mitochondrial precursor), plasma cell-induced resident endoplasmic reticulum protein, and glutathione S-transferase mu 3 were significantly underexpressed in gastric adenocarcinoma relative to adjacent non-tumor tissue samples. On the other hand, septin-2, ubiquitin-conjugating enzyme E2 N, and transaldolase were significantly overexpressed. Translationally controlled tumor protein was shown to be differentially expressed only in patients with cancer of the gastric cardia/esophageal border.
  
  
  CONCLUSIONS
  This work presents a set of possible diagnostic biomarkers, validated for the first time. It might contribute to the efforts of understanding gastric cancer carcinogenesis.
authors.affiliation: Medical Centre for Molecular Biology, Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana 1000, Slovenia.
authors.forename: Nina
authors.initials: N
authors.lastname: Kočevar
authors.forename: Federico
authors.initials: F
authors.lastname: Odreman
authors.forename: Alessandro
authors.initials: A
authors.lastname: Vindigni
authors.forename: Snježana Frković
authors.initials: SF
authors.lastname: Grazio
authors.forename: Radovan
authors.initials: R
authors.lastname: Komel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D005260:Female; D006801:Humans; D015151:Immunoblotting / Q000379:methods*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D008875:Middle Aged; D040901:Proteomics / Q000379:methods*; D015203:Reproducibility of Results; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor