Cyclooxygenase-2 is overexpressed in human cervical cancer.
Multiple lines of evidence suggest that cyclooxygenase-2 (COX-2) is an important target for preventing epithelial malignancies. Little is known, however, about the expression of COX-2 in gynecological malignancies. By immunoblot analysis, COX-2 was detected in 12 of 13 cases of cervical cancer but was undetectable in normal cervical tissue. Immunohistochemistry revealed COX-2 in malignant epithelial cells. COX-2 was also expressed in cervical intraepithelial neoplasia. The mechanism by which COX-2 is up-regulated in cervical cancer is unknown. Because the epidermal growth factor (EGF) receptor is commonly overexpressed in cervical cancer, we investigated whether EGF could induce COX-2 in cultured human cervical carcinoma cells. Treatment with EGF markedly induced COX-2 protein, COX-2 mRNA, and stimulated COX-2 promoter activity. The induction of COX-2 by EGF was suppressed by inhibitors of tyrosine kinase activity, phosphatidylinositol 3-kinase, mitogen-activated protein kinase kinase, and p38 mitogen-activated protein kinase. Moreover, overexpressing dominant-negative forms of extracellular signal-regulated kinase 1, c-Jun NH2-terminal kinase, p38, and c-Jun blocked EGF-mediated induction of COX-2 promoter activity. Taken together, these findings suggest that deregulation of the EGF receptor signaling pathway may lead to enhanced COX-2 expression in cervical cancer.
Kulkarni
S
S
Department of Medicine, New York Presbyterian Hospital-Cornell, New York 10021, USA.
Rader
J S
JS
Zhang
F
F
Liapis
H
H
Koki
A T
AT
Masferrer
J L
JL
Subbaramaiah
K
K
Dannenberg
A J
AJ
D000230:Adenocarcinoma / Q000201:enzymology*; D015152:Blotting, Northern; D015153:Blotting, Western; D018196:Carcinoma, Adenosquamous / Q000201:enzymology*; D002294:Carcinoma, Squamous Cell / Q000201:enzymology*; D051546:Cyclooxygenase 2; D005260:Female; D018773:Genes, erbB-1 / Q000502:physiology; D006801:Humans; D007124:Immunoenzyme Techniques; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010957:Plasmids; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D012509:Sarcoma / Q000201:enzymology*; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D002583:Uterine Cervical Neoplasms / Q000201:enzymology*
D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D020928:Mitogen-Activated Protein Kinases