Inhibition of Gastric Carcinoma Lymphangiogenesis with Small Interfering RNA Against VEGF2C

Objective 　To evaluate the inhibitory effect s of VEGF2C siRNA on VEGF2C expression and tumor lymphangiogenesis in nude mice SGC7901 subcutaneous xenograf t tumor models. Methods 　The nude mice model was divided randomly into 4 group s ( n = 6) : VEGF2C siRNA2liposome2suspension, lipo2 some only, siRNA only, and PBS injection. Af ter injection int ratumorally of every group the accumulation of tumor volume of each group was obtained. The expression of VEGF2C in tumor tissue was measured by Immunohistochemist ry ( IHC) . And the status of Angiogenesis and Lymphangiogenesis were examined by IHC staining with anti2CD31 monoclonal antibody and anti2L YVE21 monoclonal antibody. Results 　The expression of VEGF2C in the VEGF2C siRNA group was down regulated to 68. 3 %( P < 0. 01) compared with cont rol group. The LVD value of interference group and cont rol group was 3. 2 ±1. 3 and 9. 8 ±2. 7 respectively, reduced to 32. 7 %( P < 0. 01) of that in cont rol group. But there is no obviously variance in MVD value between interference group and cont rol group ( P > 0. 05) . Conclusion 　The VEGF2C siRNA can dramatically down regulated expression of VEGF2C in tumor tissue. And it lead to inhibition of tumor growth and tumor Lymphangiogeneis, but no effect on angiogenesis.