title: Maldi-TOF analysis of portal sera of pancreatic cancer patients: identification of diabetogenic and antidiabetogenic peptides.
abstract: BACKGROUND
  Pancreatic cancer (PC) associated diabetes mellitus (DM) might be consequent to the diabetogenic effects of tumour products, possibly acting via nitric oxide (NO). Our aims were: (1) to verify whether PC associated DM determines an increased hepatic NO and (2) using MALDI-TOF analysis, to evaluate the peptide composition of PC cell conditioned media (CM) and of portal sera from patients with PC with (n=7) or without (n=4) DM.
  
  
  METHODS
  In liver tissue homogenates of 23 patients with PC (n=17) or chronic pancreatitis (n=6) GAPDH mRNA and activity, glucose, lactate, nitrite and nitrate were assayed. MALDI-TOF analysis was performed in three PC cell lines CM, and in portal sera from patients with PC.
  
  
  RESULTS
  Higher GAPDH mRNA and nitrite were found in patients with than in patients without DM. In PC cell CM, only 9 among a total of 75 fragments identified, were tumour specific. One hundred seventy-three fragments were identified in the portal sera of patients: one was positively and six fragments were negatively correlated with DM.
  
  
  CONCLUSIONS
  Unlike liver GAPDH, NO appears to be involved in PC associated DM. In portal sera, the absence, rather than the presence, of specific fragments, appears to be correlated with the development of DM.
authors.affiliation: Department of Clinical and Experimental Medicine, University of Padova, Padova, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Valerio
authors.forename: Daniela
authors.initials: D
authors.lastname: Basso
authors.forename: Paola
authors.initials: P
authors.lastname: Fogar
authors.forename: Massimo
authors.initials: M
authors.lastname: Falconi
authors.forename: Eliana
authors.initials: E
authors.lastname: Greco
authors.forename: Claudio
authors.initials: C
authors.lastname: Bassi
authors.forename: Roberta
authors.initials: R
authors.lastname: Seraglia
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abu-Hilal
authors.forename: Filippo
authors.initials: F
authors.lastname: Navaglia
authors.forename: Carlo-Federico
authors.initials: CF
authors.lastname: Zambon
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Gallo
authors.forename: Alessandra
authors.initials: A
authors.lastname: Falda
authors.forename: Sergio
authors.initials: S
authors.lastname: Pedrazzoli
authors.forename: Mario
authors.initials: M
authors.lastname: Plebani
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D048909:Diabetes Complications / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D005260:Female; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000201:enzymology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009573:Nitrites / Q000032:analysis; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000150:complications* / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D015415:Biomarkers; D009573:Nitrites; D012333:RNA, Messenger; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases