The Expressions of MMP-2, -9 and TIMP-1, -2 after the Expression of VEGF Suppressed by siRNA in Human Tongue Squamous Cell Carcinoma in Vitro and in Vivo

Objectives To investigate the expressions of matrix metalloproteinase (MMP) -2, -9 and tissue inhibitors of metalloproteinase (TIMP) -1, -2 in human tongue squamous cell carcinoma (Tca8113) in virto and in vivo, after the expression of vascular endothelial growth factor (VEGF) suppressed by vector-based small interfering RNA (siRNA).Methods The eukaryotic expression vector taken as an experiment control and two siRNA targeting VEGF constructed in the vectors (VEGF-siRNA1, VEGF-siRNA2) were transfected into human tongue squamous cell carcinoma cell lines (Tca8113). The non-transfected Tca8113 cells were used as negative control. The transfected cells and non-transfected cells were injected subcutaneously on the back of the twenty nude-mice which were divided into four groups randomly (n=5/group), respectively. The mice were executed after 47days of transfection. The expressions of VEGF, MMP-2, -9 and TIMP-1, -2 in the cultured cells were detected by immunocytochemistry and their expressions in the xenograft tumors were detected by immunohistochemistry. Then the MMP-2, -9 and TIMP-1, -2 proteins in the extracts of the xenograft tumors were detected by gelatin zymography and western blot, respectively.Results Compared with the experimental and negative controls, the expressions of VEGF were decreased (P<0.05) in two experimental groups of the cultured cells and the xenograft tumors. There were no obvious immunohistochemical staining of MMP-2, -9 and TIMP-1, -2 in cultured cells and MMP-2 in the xenografts tissue among foure groups. There were no significant differences of the expressions of MMP-9 and TIMP-1, -2 among four groups of xenograft tumors (P>0.05).Conclusions VEGF-siRNA can down-regulate the expression of VEGF in the human tongue squamous cell carcinoma in vitro and in vivo. However, it may not influence on the expressions of MMP-2, -9 and TIMP-1, -2, efficiently.