title: Altered Activity and Expression of Cytosolic Peptidases in Colorectal Cancer.
abstract: OBJECTIVE
  The role of peptidases in carcinogenic processes and their potential usefulness as tumor markers in colorectal cancer (CRC) have been classically attributed to cell-surface enzymes. The objective of the present study was to analyze the activity and mRNA expression of three cytosolic peptidases in the CRC and to correlate the obtained results with classic histopathological parameters for tumor prognosis and survival.
  
  
  METHODS
  The activity and mRNA levels of puromycin-sensitive aminopeptidase (PSA), aminopeptidase B (APB) and pyroglutamyl-peptidase I (PGI) were measured by fluorimetric and quantitative RT-PCR methods in colorectal mucosa and tumor tissues and plasma samples from CRC patients (n=81).
  
  
  RESULTS
  1) PSA and APB activity was higher in adenomas and carcinomas than in the uninvolved mucosa. 2) mRNA levels of PSA and PGI was lower in tumors. 3) PGI activity in CRC tissue correlated negatively with histological grade, tumor size and 5-year overall survival of CRC patients. 4) Higher plasmatic APB activity was independently associated with better 5-year overall survival.
  
  
  CONCLUSIONS
  Data suggest that cytosolic peptidases may be involved in colorectal carcinogenesis and point to the determination of this enzymes as a valuable method in the determination of CRC prognosis.
authors.affiliation: 1. Department of Nursing I, School of Nursing, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Itxaro
authors.initials: I
authors.lastname: Perez
authors.affiliation: 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Lorena
authors.initials: L
authors.lastname: Blanco
authors.affiliation: 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Begoña
authors.initials: B
authors.lastname: Sanz
authors.affiliation: 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Peio
authors.initials: P
authors.lastname: Errarte
authors.affiliation: 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Usue
authors.initials: U
authors.lastname: Ariz
authors.affiliation: 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Maider
authors.initials: M
authors.lastname: Beitia
authors.affiliation: 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Ainhoa
authors.initials: A
authors.lastname: Fernández
authors.affiliation: 3. Department of Surgery, Basurto University Hospital, University of the Basque Country (UPV/EHU), Bilbao, Bizkaia, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Loizate
authors.affiliation: 4. Institute for Chemical Research, CSIC-Isla de la Cartuja, Sevilla, Spain;
authors.forename: M Luz
authors.initials: ML
authors.lastname: Candenas
authors.affiliation: 4. Institute for Chemical Research, CSIC-Isla de la Cartuja, Sevilla, Spain;
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Pinto
authors.affiliation: 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Gil
authors.affiliation: 5. Department of Anatomic Pathology, Cruces University Hospital, University of the Basque Country (UPV/EHU), Barakaldo, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: José I
authors.initials: JI
authors.lastname: López
authors.affiliation: 1. Department of Nursing I, School of Nursing, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 2. Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain ; 6. BioCruces Health Research Institute, Barakaldo, Bizkaia, Spain.
authors.forename: Gorka
authors.initials: G
authors.lastname: Larrinaga
mesh_terms: D000368:Aged; D000626:Aminopeptidases / Q000096:biosynthesis* / Q000235:genetics; D015179:Colorectal Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D003600:Cytosol / Q000201:enzymology; D018572:Disease-Free Survival; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011751:Pyroglutamyl-Peptidase I / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
chemical_list: D012333:RNA, Messenger; D000626:Aminopeptidases; C025579:enkephalin degrading enzyme; C019721:aminopeptidase B; D011751:Pyroglutamyl-Peptidase I
keywords: colorectal cancer; cytosolic; peptidases.; prognosis; soluble; survival