Adipocyte-derived leucine aminopeptidase suppresses angiogenesis in human endometrial carcinoma via renin-angiotensin system.
OBJECTIVE
Angiotensin (Ang) II was reported to induce vascular endothelial growth factor (VEGF) expression in various cells. Adipocyte-derived leucine aminopeptidase (A-LAP) is a novel member of the M1 family of zinc metallopeptidases. Enzymatic characterization demonstrated that A-LAP hydrolyzes Ang II. This study examined the role of A-LAP in angiogenesis of human endometrial carcinoma.


METHODS
We investigated whether Ang II induces VEGF expression in human endometrial carcinoma cells. To investigate the possible function of A-LAP in angiogenesis of endometrial carcinoma, we transfected A-LAP cDNA into HEC-1A cells, showing the lowest expression of A-LAP.


RESULTS
In the present study, we showed that Ang II enhanced VEGF expression in a dose-dependent manner in endometrial carcinoma cells (HEC-1A cells). Overexpression of A-LAP attenuated Ang II-induced VEGF expression in HEC-1A cells. In addition, Human umbilical vascular endothelial cell migration was increased in conditioned media from Ang II-treated wild-type cells, but not in conditioned media from Ang II-treated A-LAP-overexpressing cells (HEC-1A-A-LAP cells). In an in vivo study, we showed that A-LAP overexpression in endometrial carcinoma cells results in a reduction of VEGF immunoreactivity and the number of blood vessels within tumors.


CONCLUSIONS
Our study demonstrates that it is feasible to overexpress Ang II-degrading enzymes in cultured cells and that this overexpression attenuated some effects of exogenous and endogenous Ang II. These experiments are a first step toward the development of novel strategies to selectively antagonize locally generated Ang II and suppress VEGF-induced angiogenesis in endometrial carcinoma.
Watanabe
Yoshiteru
Y
Department of Obstetrics and Gynecology, Nagoya Graduate University School of Medicine, Nagoya, Japan.
Shibata
Kiyosumi
K
Kikkawa
Fumitaka
F
Kajiyama
Hiroaki
H
Ino
Kazuhiko
K
Hattori
Akira
A
Tsujimoto
Masafumi
M
Mizutani
Shigehiko
S
D017667:Adipocytes / Q000378:metabolism*; D000804:Angiotensin II / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D002277:Carcinoma / Q000378:metabolism*; D045744:Cell Line, Tumor; D002465:Cell Movement; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016889:Endometrial Neoplasms / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007931:Leucyl Aminopeptidase / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D009389:Neovascularization, Pathologic; D010957:Plasmids / Q000378:metabolism; D012084:Renin-Angiotensin System; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D015032:Zinc / Q000378:metabolism
D017077:Culture Media, Conditioned; D018076:DNA, Complementary; D000804:Angiotensin II; D007931:Leucyl Aminopeptidase; D015032:Zinc