ABSTRACT
<p><b>OBJECTIVE</b>To investigate the expression of COX-2 and VEGF in clear cell renal cell carcinoma (CCRCC) and their correlation with tumor angiogenesis.</p><p><b>METHODS</b>Envision immunohistochemistry was used to determine the expression of COX-2 and VEGF, and microvessel density (MVD) was marked by CD34 in 80 CCRCC tissues and 20 normal kidney tissues. The relationship between the above mentioned markers were analyzed.</p><p><b>RESULTS</b>Expressions of COX-2 and VEGF were noted in both CCRCC and normal kidney tissues. The positive rates of COX-2 and VEGF were significantly higher in CCRCC than in normal kidney (P < 0.05); The expression of COX-2 was correlated with TNM stage (P < 0.05), histological grade (P < 0.05) and lymph node metastasis (P < 0.05) in CCRCC, but not with age (P = 0.663) and diameter of tumor (P = 0.528). Both COX-2 expression (r = 0.851, P < 0.01) and VEGF expression (r = 0.736, P < 0.01) were significantly associated with MVD in CCRCC. There was a positive correlation between expression of cox-2 and that of VEGF in CCRCC.</p><p><b>CONCLUSION</b>COX-2 expression is correlated with tumor angiogenesis in CCRCC. It is likely that VEGF is one of the most important mediators in the COX-2 angiogenic pathway.</p>