Suppression Of VEGF Expression And Tumor Growth By Vector-Based Sirna In Human Toungue Squamous Carcinoma Cell Line In Vitro And In Vivo

Objectives To assess supression effects of vector-based small interfering RNA(siRNA)on vascular endothelial growth factor(VEGF)expression of human tongue squamous carcinoma cell line(Tca8113)and tumour growth and angiogenesis in vitro and in vivo.Methods Two vector-based siRNA targeting VEGF(PU-VEGF-siRNA1, PU-VEGF-siRNA2)and eukaryotic expression vector(experiment control)were transfected into Tca8113 cells by lipofectamine2000,and screened by G418. Non-transfected cells was used as negative control.The proliferation and apoptosis,cell cycle,VEGF mRNA expression in Tca8113 cells were detected by 3-(4,5-dimthy-2-2thiazoly)2,5-dipheny-2H-tetrazoliun bromide(MTT),flow cytometry,and reverse transcription polymerse chain reaction(RT-PCR), respectively,after transfection.Twenty nude-mice were divided into 4 groups randomly,and then the transfected cells and non-transfected cell were subcutaneous injected on the back of mice,respectively.The tumor volume, weight,and growth curve of every groups were recorded.The protein expression of VEGF and Microvessel density(MVD)of tumor tissue were detected by immunohistochemical technique.The apoptosis of the neoplasms in nude mice was quantitatively determined by TdT mediated dUTP nick end labeling (TUNEL).Results Compared with experiment and negative controls,the expression of VEGF mRNA and proliferation and apoptosis rate were significantly descreased(P＜0.05),the percentage of S stage was significantly lower(P＜0.05), the growth of tumors was significantly reduced,and tumor volume and weight were decreased(P＜0.05),VEGF expression and MVD significantly were decreased in two experiment groups(P＜0.05).Numerous apoptotic cells were found in the experimental groups,but few in the controls.The apoptotic indices were significantly higher in the experimental group than those in the controls (P＜0.05).But there were not statistically significantly difference of those between two controls(P＞0.05).There was no statistically significantly difference of those between two control groups.Conclusions Vector-based siRNAs targeting VEOF are efficient in down-regulating VEGF expression in Tca8113 cell,suppressing angiogenesis in vivo and the growth both in vitro and in vivo.