Abstract: BACKGROUND AND AIM: To investigate the expression of VEGF-C, VEGFR-3 and COX-2 in oral squamous cell carcinoma(OSCC), and the correlation with lymphangiogenesis and lymph node metastasis. MATERIALS AND METHODS: Immunohistochemical SP method for VEGF-C, VEGFR-3 and COX-2 were performed in 60 cases of OSCC, 23 cases of precancerous change and 19 benign lesion specimens. The lymphatic vessel density(LVD) in the tumor was counted and analyzed with clinicopathologic parameters. RESULTS: Compared with benign and precancerous change, the expressions of VEGF-C, LVD and COX-2 were significantly higher in OSCC (P<0.05). The expressions of VEGF-C and LVD were significantly correlated with lymphatic metastasis (P<0.05); COX-2 was obviously related with clinical stage and lymphatic metastasis(P<0.05). The expression of COX-2 was closely correlated with that of VEGF-C(r=0.519,P<0.01),with LVD positively correlated with their expression levels(r=0.661,P<0.01 and r=0.485, P<0.01,respectively). CONCLUSION: The expression rates of COX-2 and VEGF-C were high in OSCC. COX-2 may participate in VEGF-C lymphangiogenic pathway and play an important role in the lymph node metastasis of OSCC.

Key words: oral squamous cell carcinoma, VEGF-C, COX-2, lymphatic metastasis