Abstract: Objective To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and the angiogenesis in human malignant melanoma (MM). Methods Tissue sections from 31 MM patients were examined. The protein expression of eNOS and VEGF was detected using immunohistochemistry technique and morphological quantitative analysis. Microvessel density (MVD) was also counted by immunostaining with anti-FⅧRAg antibody. Results (1)The positive staining of eNOS and VEGF was detected in 71.4% (24 cases) and 83.9% (26 cases) of MM respectively. As negative control there was no staining in the nevus pigmentosus tissue sections. (2)There was a positive correlation between the expression of eNOS and VEGF in MM. (3)The positive correlation was also found between the MVD and the expression of eNOS and VEGF in MM. The number of MVD was higher in MM than that in nevus pigmentosus tissue. (4)The lymphatic metastasis was not correlated with the expression of eNOS and VEGF. Conclusion The number of the MVD increases along with the high expression of eNOS and VEGF in MM.

Key words: Melanoma, Nitric-oxide synthase, Endothelial growth factors, Neovascularization, pathologic