The correlation between VEGF-C and COX-2 mRNA expression in colon carcinoma and its role in metastasis

Objective To study the expressions of vascular endotheliol growth factor C(VEGF-C), cyclooxygenase-2(COX-2) mRNA and microvessel density (MVD) in colon carcinoma and their significance in the angiogenesis, lymph node metastasis and clinical pathologic characteristics. Methods Expression of COX-2 mRNA was evaluated by in situ hybridization method and that of VEGF-C and CD34 was detected immunohistochemically by MaxvisionTM method in 62 cases of colon carcinoma, 22 cases of colon adenoma and 22 cases normal colon tissues. Results The percentage of positive VEGF-C was 74.19% in 62 cases of colon carcinoma,which was significantly higher than that of colon adenoma and normal colon tissues(P0.01).Expressions of COX-2 mRNA were detected in a significantly greater proportion of colon carcinoma and adenoma samples than those in the normal colon tissues[74.19% vs. 36.36%(P0.01) and 72.73% vs. 36.36%(P0.05)]. The expression of MVD was significantly greater in colon carcinoma samples than that in adenoma and normal tissues of colon(P0.01).In 62 cases with colon carcinoma, the percentage of VEGF-C expression was 82.61%, which was positively correlated with the expressions of VEGF-C and COX-2 mRNA(P0.01).The positive expression of COX-2 mRNA in high differentiation group was significantly higher than that in low differentiation group(P0.05).The expression of MVD in advanced carcinoma group was significantly greater than that in early carcinoma group(P0.01).MVD in the patients with lymphatic metastasis and angiogenesis infiltration was higher than that in those without lymphatic metastasis and angiogenesis infiltration(P0.01 or P0.05).Conclusion COX-2 may play an important role in tumor cell proliferation and lymphatic metastasis by upregulating VEGF-C in colon carcinoma.