[Relationship of expression of inducible nitric oxide synthase to microvessel density in oral squamous cell carcinomas].

OBJECTIVE: To study expression of inducible nitric oxide synthase (iNOS) in oral squamous cell carcinomas (OSCC) and its relations to microvessel density (MVD) and lymphatic metastasis. METHODS: With 9 cases of normal oral mucosa as control, the expression rate of iNOS in 41 cases of OSCC was evaluated by immunohistochemstry SP staining. With CD34 as label, MVDs of these cases were also detected. RESULTS: The iNOS expression rate of OSCC cases was 63.41%(26/41), while no positive expression was seen in 9 cases of normal oral mucosa. Anymore, the expression rate of N+ group was 85.00% while that of N group 42.90%, the rate between them was significantly different (P<0.01). There was correlation between MVD and lymphatic metastasis (rs=0.51, P<0.01). MVDs in groups of different iNOS expression( approximate, equals +++) were 29.667+/-6.945, 34.833+/-4.579, 46.357+/-6.687, 54.167+/-5.565, respectively, and were significantly different with each other (P<0.001). CONCLUSION: There is high expression rate of iNOS in OSCC, and it has close relation to lymphatic metastasis; angiogenesis may facilitate lymphatic metastasis of OSCC, and expression of iNOS has positive relation to MVD in OSCC.