title: Pre-treatment plasma proteomic markers associated with survival in oesophageal cancer.
abstract: BACKGROUND
  The incidence of oesophageal adenocarcinoma is increasing worldwide but survival remains poor. Neoadjuvant chemotherapy can improve survival, but prognostic and predictive biomarkers are required. This study built upon preclinical approaches to identify prognostic plasma proteomic markers in oesophageal cancer.
  
  
  METHODS
  Plasma samples collected before and during the treatment of oesophageal cancer and non-cancer controls were analysed by surface-enhanced laser desorption/ionisation time-of-flight (SELDI-TOF) mass spectroscopy (MS). Protein peaks were identified by MS in tryptic digests of purified fractions. Associations between peak intensities obtained in the spectra and clinical endpoints (survival, disease-free survival) were tested by univariate (Fisher's exact test) and multivariate analysis (binary logistic regression).
  
  
  RESULTS
  Plasma protein peaks were identified that differed significantly (P<0.05, ANOVA) between the oesophageal cancer and control groups at baseline. Three peaks, confirmed as apolipoprotein A-I, serum amyloid A and transthyretin, in baseline (pre-treatment) samples were associated by univariate and multivariate analysis with disease-free survival and overall survival.
  
  
  CONCLUSIONS
  Plasma proteins can be detected prior to treatment for oesophageal cancer that are associated with outcome and merit testing as prognostic and predictive markers of response to guide chemotherapy in oesophageal cancer.
authors.affiliation: Dundee Cancer Centre, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK. peter.kelly@axis-shield.com
authors.forename: P
authors.initials: P
authors.lastname: Kelly
authors.forename: F
authors.initials: F
authors.lastname: Paulin
authors.forename: D
authors.initials: D
authors.lastname: Lamont
authors.forename: L
authors.initials: L
authors.lastname: Baker
authors.forename: S
authors.initials: S
authors.lastname: Clearly
authors.forename: D
authors.initials: D
authors.lastname: Exon
authors.forename: A
authors.initials: A
authors.lastname: Thompson
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000401:mortality; D000328:Adult; D000368:Aged; D016632:Apolipoprotein A-I / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood; D001798:Blood Proteins / Q000032:analysis*; D018572:Disease-Free Survival; D004938:Esophageal Neoplasms / Q000097:blood* / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011228:Prealbumin / Q000032:analysis*; D040901:Proteomics / Q000379:methods; D000685:Serum Amyloid A Protein / Q000032:analysis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D016632:Apolipoprotein A-I; D014408:Biomarkers, Tumor; D001798:Blood Proteins; D011228:Prealbumin; D000685:Serum Amyloid A Protein