Abstract:Object To investigate the expression of inducible nitric oxide synthase(iNOS)and vascular endothelial growth factor(VEGF) in human esophageal squamous cell carcinoma and their clinical significances,and to evaluate the correlation between the expression of iNOS and VEGF. Methods Immunohistochemical SABC methond was used to detect the expression of iNOS and VEGF in 52 cases of esophageal squamous cell carcinoma and 20 cases of paired para-carcinama. The correlation between the expression of iNOS and VEGF was analyzed statistically. And the correlation between the expression of iNOS and VEGF and the clinical pathological features of the patients was analyzed statistically. Results The positive expression rates of iNOS and VEGF in esophageal squamous cell carcinoma were 63.46％(33/52) and 67.31％(35/52),respectively. The positive expression rates of iNOS and VEGF in paired para-carcinama tissues were 10%（2/20）and 20%（4/20）respectively. The positive expression rates of iNOS and VEGF in esophageal squamous cell carcinoma were significantly higher than those in paired para-carcinama tissues（P﹤0.01）. There was significiat correlation between the expression of iNOS, VEGF and the pathological grade（P﹤0.01）,clinic TNM stage（P﹤0.05）, lymph noed metastasis（P﹤0.05），but there was no correlation between the expression of iNOS, VEGF and the patients sex（P＞0.05）. Expression of iNOS was positively correlated with that of VEGF（ｒ＝0.7482，P﹤0.01）. Conclusion iNOS and VEGF are highly expressed and correlated in esophageal carcinoma. It is speculated that a common activation mechanism may coexists between the two genes. The expression of iNOS and VEGF plays an important role in the malignant progression.

Key words:Esophageal neoplasms,Nitric oxide synthas,Vascular endothelial growth factors