Dipeptidyl peptidase IV expression in endometrial endometrioid adenocarcinoma and its inverse correlation with tumor grade.
OBJECTIVE
Dipeptidyl peptidase IV (DPPIV)/CD26 is a cell surface aminopeptidase. This study investigated the expression and localization of DPPIV in endometrial endometrioid adenocarcinomas of different grades.


METHODS
Immunohistochemical analysis was performed by using DPPIV and regulated on activation, normal T-cell expressed and secreted (RANTES) specific monoclonal antibodies. Cell proliferation was evaluated by bromodeoxyuridine (BrdU) uptake assay.


RESULTS
Immunohistochemical analyses showed that DPPIV was strongly or moderately stained in glandular cells of the normal secretory phase. In endometrial adenocarcinoma, the DPPIV expression decreased with advancing grade (P <.01). Furthermore, RANTES, one of the possible DPPIV substrates, was highly expressed in all grades of endometrial adenocarcinoma cells. The addition of RANTES to endometrial adenocarcinoma cells increased proliferation in a concentration-dependent manner.


CONCLUSIONS
DPPIV is expressed in normal endometrial glandular cells, but its expression in endometrial adenocarcinoma is down-regulated with increasing grade. Our data also suggest a regulatory role of this ectoenzyme in neoplastic transformation and progression of endometrial adenocarcinomas possibly by degrading certain bioactive peptides such as RANTES.
Khin
Ei Ei
EE
Departments of Obstetrics and Gynecology, Nagoya University Graduate School of Medicine, Japan.
Kikkawa
Fumitaka
F
Ino
Kazuhiko
K
Kajiyama
Hiroaki
H
Suzuki
Takahiro
T
Shibata
Kiyosumi
K
Tamakoshi
Koji
K
Nagasaka
Tetsuro
T
Mizutani
Shigehiko
S
D018269:Carcinoma, Endometrioid / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D018946:Chemokine CCL5 / Q000008:administration & dosage / Q000378:metabolism; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D016889:Endometrial Neoplasms / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D009994:Osmolar Concentration
D018946:Chemokine CCL5; D018819:Dipeptidyl Peptidase 4