Increased prolyl endopeptidase activity in human neoplasia

• Published in: Regulatory peptides Vol. 163; no. 1; pp. 102 - 106
• Main Authors: Larrinaga, Gorka, Perez, Itxaro, Blanco, Lorena, López, José I., Andrés, Leire, Etxezarraga, Carmen, Santaolalla, Francisco, Zabala, Aitor, Varona, Adolfo, Irazusta, Jon
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 09.08.2010; Elsevier
• Subjects: Adult; Aged; Aged, 80 and over; Bioactive peptides; Biological and medical sciences; Cancer; Colorectal Neoplasms - enzymology; Colorectal Neoplasms - metabolism; Female; Fundamental and applied biological sciences. Psychology; Humans; Kidney Neoplasms - enzymology; Kidney Neoplasms - metabolism; Laryngeal Neoplasms - enzymology; Laryngeal Neoplasms - metabolism; Male; Middle Aged; Mouth Neoplasms - enzymology; Mouth Neoplasms - metabolism; PEP; Prolyl endopeptidase; Prolyl oligopeptidase; Serine Endopeptidases - metabolism; Testicular Neoplasms - enzymology; Testicular Neoplasms - metabolism; Thyroid Neoplasms - enzymology; Thyroid Neoplasms - metabolism; Tumor markers; Vertebrates: endocrinology; Prolyl endopeptidase; PEP; Tumor markers; Bioactive peptides; Prolyl oligopeptidase; Cancer; Human; Peptides; Malignant tumor
• ISSN: 0167-0115; 1873-1686
• DOI: 10.1016/j.regpep.2010.03.012

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.