Cyclooxygenase-2 promotes prostate cancer progression.
BACKGROUND
Cyclooxygenase (COX) -2, an inducible isoform of COX, has been observed to be expressed in prostate cancer. Several studies have reported that COX-2 overexpression is associated with carcinogenesis, cell growth, angiogenesis, apoptosis, and invasiveness in a variety of tumor types.


METHODS
To investigate the function of COX-2 in prostate cancer directly, we stably transfected human full-length COX-2 cDNA into LNCaP cells (LNCaP-COX-2), which express low levels of endogenous COX-2.


RESULTS
The level of COX-2 mRNA and protein and the COX activity in COX-2 LNCaP-COX-2 cells was significantly increased compared with parent and control-transfected cells. Overexpression of COX-2 increased both proliferation in vitro and tumor growth rate in vivo. However, the pro-tumor effect was neither associated with changes of androgen receptor (AR) expression level nor AR activity. Furthermore, addition of the major metabolites of COX-2-mediated arachidonic acid metabolism did not alter the proliferation of LNCaP-COX-2 cells in vitro. LNCaP-COX-2 cells had increased secretion of vascular endothelial growth factor (VEGF) protein, suggesting that angiogenesis induced by COX-2 stimulates tumor growth in vivo.


CONCLUSIONS
These data demonstrate that COX-2 contributes to prostate cancer progression and suggest that it mediates this effect, in part, through increased VEGF.
Fujita
Hiroshi
H
Department of Urology, Kanazawa University, Kanazawa-City, Japan.
Koshida
Kiyoshi
K
Keller
Evan T
ET
Takahashi
Yoshitake
Y
Yoshimito
Tanihiro
T
Namiki
Mikio
M
Mizokami
Atsushi
A
D000818:Animals; D015153:Blotting, Western; D002455:Cell Division / Q000187:drug effects; D051546:Cyclooxygenase 2; D016228:Endothelial Growth Factors / Q000096:biosynthesis; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D008222:Lymphokines / Q000096:biosynthesis; D008297:Male; D008565:Membrane Proteins; D051379:Mice; D016513:Mice, SCID; D009376:Neoplasms, Hormone-Dependent / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000378:metabolism; D009578:Nitrobenzenes / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism*; D017430:Prostate-Specific Antigen / Q000235:genetics; D011471:Prostatic Neoplasms / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011944:Receptors, Androgen / Q000096:biosynthesis / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013449:Sulfonamides / Q000494:pharmacology; D014162:Transfection; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D036341:Intercellular Signaling Peptides and Proteins; D007527:Isoenzymes; D008222:Lymphokines; D008565:Membrane Proteins; D009578:Nitrobenzenes; D012333:RNA, Messenger; D011944:Receptors, Androgen; D013449:Sulfonamides; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D017430:Prostate-Specific Antigen