Study on the Association Between COX-2、VEGF and MVD Expression in Colorectal Adenocarcinoma

Objective To investigate the association between cyclooxygenase-2 (COX-2),vascular endothelial growth factor (VEGF) expression,microvessel density (MVD) and proliferating cell nuclear antigen (PCNA) or the histological type in colorectal adenocarcinoma.Methods COX-2,VEGF and PCNA expression were studied by means of immunohistochemistry in 50 cases of colorectal adenocarcinomas and 26 cases of colorectal adenomas.MVD was assessed after CD 34 staining in 3×200 fields in the most vascularized areas.Results COX-2 and VEGF were overexpressed in colorectal adenocarcinoma (78% and 76% vs 32%) compared with normal colon mucosa.COX-2 positively correlated with the levels of VEGF expression.The low MVD of colorectal adenocarcinoma could participate in their overall better prognosis.Conclusion Overexpression of COX-2 and VEGF occur early during colorectal carcinogenesis which contribute to tumour formation,development and angiogenesis.