title: Increased prolyl endopeptidase activity in human neoplasia.
abstract: Prolyl endopeptidase (EC 3.4.21.26) (PEP) is a serine peptidase that converts several biologically active peptides. This enzyme has been linked to several neurological, digestive, cardiovascular and infectous disorders. However, little is known about its involvement in neoplastic processes. This study analyzes fluorimetrically cytosolic and membrane-bound PEP activity in a large series (n=122) of normal and neoplastic tissues from the kidney, colon, oral cavity, larynx, thyroid gland and testis. Cytosolic PEP activity significantly increased in clear cell renal cell carcinoma, urothelial carcinoma of the renal pelvis and head and neck squamous cell carcinoma. Both cytosolic and membrane-bound PEP activity were also increased in colorectal adenomatous polyps. These data suggest the involvement of PEP in some mechanisms that underlie neoplastic processes.
authors.affiliation: Department of Physiology, School of Medicine and Dentistry, Leioa, Bizkaia, Spain. gorka.larrinaga@ehu.es
authors.forename: Gorka
authors.initials: G
authors.lastname: Larrinaga
authors.forename: Itxaro
authors.initials: I
authors.lastname: Perez
authors.forename: Lorena
authors.initials: L
authors.lastname: Blanco
authors.forename: José I
authors.initials: JI
authors.lastname: López
authors.forename: Leire
authors.initials: L
authors.lastname: Andrés
authors.forename: Carmen
authors.initials: C
authors.lastname: Etxezarraga
authors.forename: Francisco
authors.initials: F
authors.lastname: Santaolalla
authors.forename: Aitor
authors.initials: A
authors.lastname: Zabala
authors.forename: Adolfo
authors.initials: A
authors.lastname: Varona
authors.forename: Jon
authors.initials: J
authors.lastname: Irazusta
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000378:metabolism; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000201:enzymology* / Q000378:metabolism; D007822:Laryngeal Neoplasms / Q000201:enzymology* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000201:enzymology* / Q000378:metabolism; D000085822:Prolyl Oligopeptidases; D012697:Serine Endopeptidases / Q000378:metabolism*; D013736:Testicular Neoplasms / Q000201:enzymology* / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000201:enzymology* / Q000378:metabolism
chemical_list: D012697:Serine Endopeptidases; C000705287:PREPL protein, human; D000085822:Prolyl Oligopeptidases