Abstract
Purpose::
Cyclooxygenase-2 (COX-2) has been broadly investigated as a potential anti-angiogenic target in both neoplastic and non-neoplastic diseases. COX-2 has previously been shown to modulate the expression of VEGF and its receptors, suggesting that anti-COX-2 strategies represent prospective adjunct therapies to currently established anti-VEGF modalities. Previous studies have investigated the efficacy of anti-COX-2 therapies in inhibiting choroidal neovascularization in animal models, but to date no study has examined COX-2 expression in human choroidal neovascular membranes. The aim of this study was to investigate the possible expression of COX-2 in human choroidal neovascular membranes.
Methods::
Formalin-fixed, paraffin-embedded sections of choroidal neovascular membranes excised from 16 patients with wet age-related macular degeneration (AMD) were used for this study. Sections were subjected to immunohistochemistry using a mouse anti-human monoclonal COX-2 antibody. Staining was classified as either negative or positive in retinal pigment epithelial (RPE) cells, endothelial cells of blood vessels, and fibroblasts.
Results::
Eleven of 16 choroidal neovascular membranes stained positive for COX-2 in RPE cells (69%), with six of these also expressing COX-2 in vessels (38%) and five demonstrating expression in fibroblasts (31%). None of the sections that were negative for COX-2 in the RPE showed COX-2 expression in the other structures.
Conclusions::
The expression of COX-2 in human choroidal neovascular membranes suggests a possible role for this modulator in AMD pathogenesis. Specific targeting of COX-2 may represent a therapeutic approach to managing the inflammatory component of this disease. Moreover, anti-COX-2 strategies may prove to be beneficial in preventing disease progression in high-risk patients.
Keywords: age-related macular degeneration • choroid: neovascularization • immunohistochemistry