Cyclooxygenase-2 and Vascular Endothelial Growth Factor Expression and Their Correlation with Angiogenesis in Gastric Carcinomas

Objective: The aim of this study was to investigate the expression of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in gastric carcinomas and lymph node metastasis and their relationship with angiogenesis and prognostic histopathological parameters. Materials and Methods: COX-2 and VEGF expression and microvessel density (MVD) grade identified by antibodies against CD34 were investigated immunohistochemically in 33 patients with gastric carcinoma. Results: The expression of COX-2 was 96.9% in normal mucosa and 87.8% in gastric carcinoma. Although COX-2 expression in mucosa was higher than in carcinoma, the difference was not statistically significant. The COX-2 positivity rates in lymph nodes were significantly higher in patients with vascular invasion (p<0.01). The expression of VEGF was 100% in normal mucosa and 93.9% in gastric carcinoma. VEGF levels in mucosa were significantly higher than in carcinoma (p=0.05). MVD grade in mucosa was significantly higher than in gastric carcinoma (p<0.01). MVD values were significantly higher in poorly differentiated carcinomas than in well and moderately differentiated carcinomas (p<0.05). There was no association between COX-2 and VEGF expression and MVD grade in tumor tissues and metastatic lymph nodes. There was no correlation of clinicopathological parameters with COX-2 and VEGF expression and MVD grade. Conclusion: Our results suggest that the MVD in gastric carcinoma may correlate with tumor grade, but the precise roles of COX-2 and VEGF in gastric cancers are not yet fully understood. Further studies with large series are needed to clarify the importance of COX-2, VEGF and MVD in cancer progression.