Increased APN/CD13 and acid aminopeptidase activities in head and neck squamous cell carcinoma.
BACKGROUND
Involvement of peptidases in carcinogenic processes of several tumor types has been investigated in recent years. Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers worldwide and accounts for more than 90% of all head and neck cancers. Increased understanding of its pathophysiology has led to implication of several proteinases, specially matrix metalloproteinases, in its genesis, growth, and dissemination. However, very little is known about involvement of peptidases in this neoplasm.


METHODS
Seventeen HNSCC tissue samples were selected for the study. Tumor and normal tissue samples were frozen for enzymatic study. The catalytic activity for a pool of peptidases (PSA, APN/CD13, APB, APA, Asp-AP, CAP, DPPIV/CD26, NEP/CD10, and PGI) was measured fluorometrically.


RESULTS
The activity of 2 cell surface aminopeptidases (APN/CD13 and APA) and a cytosolic aminopeptidase (Asp-AP) was significantly increased in HNSCC tissues.


CONCLUSIONS
These data show the involvement of cell surface and cytosolic peptidases in the mechanisms underlying HNSCC.
Pérez
Itxaro
I
Department of Physiology, School of Medicine and Dentistry, University of the Basque Country, Bilbao, Spain.
Varona
Adolfo
A
Blanco
Lorena
L
Gil
Javier
J
Santaolalla
Francisco
F
Zabala
Aitor
A
Ibarguen
Agustin Martínez
AM
Irazusta
Jon
J
Larrinaga
Gorka
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018826:CD13 Antigens / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000201:enzymology* / Q000503:physiopathology; D005260:Female; D043384:Glutamyl Aminopeptidase / Q000378:metabolism*; D006258:Head and Neck Neoplasms / Q000201:enzymology* / Q000503:physiopathology; D006801:Humans; D007150:Immunohistochemistry; D007822:Laryngeal Neoplasms / Q000201:enzymology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged
D018826:CD13 Antigens; D043384:Glutamyl Aminopeptidase