Cyclooxygenase-2 expression in primary and metastatic Merkel cell carcinoma.
Cyclooxygenase-2 (COX-2) is involved in the development and progression of many tumors, and its inhibition has been shown to block tumor growth. This study examined COX-2 expression in primary and metastatic Merkel cell carcinoma (MCC). Formalin-fixed paraffin-embedded tissues from 26 primary MCCs and 7 lymph node metastases were stained immunohistochemically with a monoclonal antibody directed against COX-2, and the percentage and intensity of staining were analyzed semiquantitatively. Immunopositivity for COX-2 was found in 20 primary tumors (77%), and was diffuse in 16 of them (80%). Staining intensity was strong in 5 tumors (19%), moderate in 6 (23%), and weak in 9 (35%). Five metastases (71%) showed similar staining. Prominent mitotic activity was associated with more diffuse COX-2 immunopositivity. No association was found between COX-2 expression and outcome. This study confirms that most MCCs express COX-2 and shows that COX-2 expression is related to one parameter of aggressive behavior--a high mitotic rate--but not to any others. The possibility of treating MCC with COX-2 inhibitors should be considered.
Joachims
Zohar
Z
Department of Otolaryngology, Rabin Medical Center, Beilinson Hospital, Petah Tiqwa, Israel.
Feinmesser
Raphael
R
Purim
Ofer
O
Halpern
Marisa
M
Brenner
Baruch
B
Fenig
Eyal
E
Roizman
Pepi
P
Sulkes
Jaqueline
J
Feinmesser
Meora
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D015266:Carcinoma, Merkel Cell / Q000201:enzymology* / Q000473:pathology / Q000556:secondary*; D051546:Cyclooxygenase 2 / Q000096:biosynthesis* / Q000235:genetics* / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008938:Mitosis / Q000235:genetics / Q000276:immunology; D009361:Neoplasm Invasiveness; D012878:Skin Neoplasms / Q000201:enzymology* / Q000473:pathology*
D000911:Antibodies, Monoclonal; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human