血管内皮生长因子RNA干扰效应对鼻咽癌生长的影响

Effect of vascular endothelial growth factor RNA interference on nasopharyngeal carcinoma

目的研究RNA干扰(RNA interference)效应对人鼻咽癌低分化上皮细胞株CNE血管内皮生长因子(vascular endothelial growth factor,VEGF)基因表达及肿瘤生长的抑制作用。方法体外转录试剂盒合成VEGF siR-NA;荧光素标记试剂盒标记siRNA;脂质体法将siRNA转入CNE细胞株。荧光显微镜下观察siRNA的转染效率;ELISA检测siRNA对VEGF蛋白表达的抑制作用;用VEGF siRNA转染过的CNE细胞注射入裸鼠,监测裸鼠肿瘤的大小,并采用HE染色,光镜下观察VEGF siRNA对肿瘤组织的影响。结果在VEGF siRNA转染后的CNE细胞株,VEGF的表达得到有效地抑制。对鼻咽癌异种移植肿瘤裸鼠内的治疗观察表明,肿瘤生长在治疗3周后显著减少,病理切片HE染色siRNA组肿瘤的坏死灶增多。结论体外转录合成的siRNA能特异有效地下调VEGF基因的表达,提示用2′-脱氧修饰的VEGF特定siRNA能作为一种有效的肿瘤制剂,为抗鼻咽癌基因治疗提供了新的思路。

Objective To study the inhibition of vascular endothelial growth factor（VEGF） gene expression by RNA interference in CNE cell and its inhibitory effects on tumor growth in nude mice. Methods VEGF small interfering RNA（siRNA） gene were synthesized by short interfering RNA construction kit ; Fluorescent labeled siRNA were performed with FAM silencer TM siRNA labeling kit; siRNA was transfected into CNE cells by using lipofectamine TM2000 reagent; siRNA transfection efficencies were analyzed by fluorescent micmscopy;Iinhibition of VEGF was detected by ELISA;CNE cells were injected into nude mice and the tumor - bearing nude mice were treated with VEGF siRNA. Modified NC siRNA or saline was used as control. Size of tumors was measured with digital calipers. Tumor tissues were embedded in paraffin and the secfiongs were stained by HE, Results The expression of VEGF was effectively suppressed by VEGF specific siRNA after a single dose as measured by ELISA. Tumor growth was significantly reduced after three week＇s treatment. By histological study, more necrosis areas were detected after VEGF siRNA gene transfection. Conclusions The synthesized siRNA in vitro were able to down-regulate the expression of VEGF. It is suggested that VEGF specific siRNA can be used as a potential agent for tumor therapy and provide a new method for gene therapy of asopharyngeal carcinoma.