超声与造影剂促VEGF siRNA抑制鼻咽癌的实验研究  

Ultrasound and contrast agents enhance VEGF siRNA-mediated anti-cancer effect on human nasopharyngeal carcinoma

作　　者：张海[1] 李莹 陈善义[3] 冯程[1] 焦阳[1] 李华锋[1] 陈彤[4] 陈泽建 

机构地区：[1]深圳市人民医院暨南大学第二临床医学院超声科,518020 [2]深圳市人民医院暨南大学第二临床医学院放射科,518020 [3]深圳市肿瘤研究所 [4]深圳市肿瘤研究所外科 [5]深圳赛百诺基因技术有限公司

出　　处：《中华超声影像学杂志》2008年第6期538-541,共4页Chinese Journal of Ultrasonography

基　　金：基金项目：广东省自然科学基金项目（05009076）

摘　　要：目的以超声辐照与超声造影剂（BR14与Levovist）微泡为研究对象，通过体外和体内实验对其促进siRNA转染的方法学进行研究。方法将合成的2＇-。脱氧血管内皮（细胞）生长因子-siRNA（VEGF 2＇-deoxy siRNA，VdsR）进行鼻咽癌细胞与荷瘤裸鼠动物实验。首先进行超声照射下的VdsR定点释放实验，然后以不同超声造影剂作载体，比较VdsR抑制肿瘤生长作用。结果在体外实验中VdsR完全抑制鼻咽癌细胞表达VEGF。在动物试验中单纯超声照射显著增强VdsR导致的肿瘤抑制作用，而对随机序列siRNA没有影响。当加用BR14微泡时则进一步增强VdsR导致的抑瘤作用，然而Levovist微泡则无显著影响。结论 超声照射和微泡造影剂BR14可以显著增强siRNA转染的作用，具有分子靶向治疗的应用潜力。Objective To study the enhancing effect of ultrasound plus microbubble on small interference RNA （siRNA） transfection in vitro and in vivo. Methods Human vascular epithelial growth factor （VEGF） siRNA with 2＇ deoxy modification （VEGF 2 ＇-deoxy siRNA, VdsR） was used. The human CNE cells （from nasopharyngeal carcinoma） line was used for in vitro cell-based experiments and in vivo mouse xenograft model. Two different microbubble agents, BR14 and Levovist, were used together with the RNA transfection reagent RNA-mate. ELISA and RT-PCR assays were used to assess VEGF gene expression. Immunohistochemical staining （IHC） was performed to assess CD31 expression in xenograft tumors. Results VdsR transfection in CNE cells abolished VEGF expression as determined by ELISA experiments. In the first mouse xenograft experiment, ultrasound exposure dramatically enhanced VdsR-mediated tumor inhibition. In the second mouse xenograft experiment,when VdsR was mixed with the microbubble reagents and then injected into xenografts, ultrasound exposure significantly reduced tumor growth in BR14-mixed VdsR group but not in the Levovist-mixed VdsR group compared to the control. RT-PCR experiments demonstrated that VEGF expression in ultrasound-exposed tumors was significantly lower than that in the control. Meanwhile,VEGF expression in the tumor tissue treated by BR14-mixed VdsR declined as compared with the controls. Tumor vascular density as measured by CD31 immunostaining was significantly decreased in ultrasound-exposed tumors compared to the control. Conclusions Ultrasound exposure and/or microbubble can significantly enhance delivery and the efficiency of VdsR-mediated anti-tumor effects,and should be a location-specific enhancement approach for siRNA-based anti-cancer therapy.

关 键 词：超声检查 微气泡 鼻咽肿瘤 基因转移技术 

分 类 号：R686[医药卫生—骨科学]