Nie Fang, Xu Hui-Xiong, Lu Ming-De, Wang Ying, Tang Qing
Department of Medical Ultrasonics, Institution of Diagnostic and Interventional Ultrasound, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People's Republic of China.
J Drug Target. 2008 Jun;16(5):389-95. doi: 10.1080/10611860802088846.
The aim of this study was to assess the effect of anti-angiogenic gene therapy for hepatocelluar carcinoma (HCC) treated by microbubble-enhanced ultrasound exposure.
Forty C57BL/6J female mice were inoculated s.c. with Hepa1-6 tumor cell line. Herpes simplex virus thymidine kinase under the control of kinase domain-containing receptor (KDR, angiogenic growth factor's corresponding receptor) promoter was used. Plasmid DNA with or without microbubble contrast agent of SonoVuetrade mark was i.v. injected. Ultrasound (1 MHz, 2 W/cm(2), 5 min) was delivered to hepatic carcinomas in mice. The KDR-tk gene transfer was followed by ganciclovir (GCV) injection for 10 days and then the diameters of tumors were measured every 4 days till 28 days. The survivals of tumor-bearing mice were observed. PCR analysis and immunohistochemistry measurements revealed expression of the transfected gene. Transferase-mediated dUTP nick end labeling staining was used to detect apoptotic cells.
Compared with the group treated by ultrasound alone, KDR-tk gene treatment treated by ultrasound combined with SonoVue restrained tumor growth and increased survival time of tumor-bearing mice; microvessel density in group mediated by ultrasound and SonoVue was significantly lower than that in group ultrasound alone (12.3 +/- 1.4 vs. 27.4 +/- 3.2, P < 0.05). An apoptosis index increased in the group treated by ultrasound and SonoVue compared with the group treated by ultrasound alone (25 +/- 3.6 vs. 36 +/- 3.8, P < 0.05), whereas there was no significant difference between group mediated by SonoVue alone and group phosphate-buffered saline alone (17 +/- 1.8 vs. 14 +/- 1.2, P>0.05).
Gene therapy mediated by ultrasound exposure enhanced by a microbubble contrast agent may become a new treatment option for persistent HCC.
本研究旨在评估微泡增强超声照射下抗血管生成基因治疗对肝细胞癌（HCC）的疗效。
40只C57BL/6J雌性小鼠皮下接种Hepa1-6肿瘤细胞系。使用在含激酶结构域受体（KDR，血管生成生长因子的相应受体）启动子控制下的单纯疱疹病毒胸苷激酶。静脉注射含或不含SonoVue商标微泡造影剂的质粒DNA。对小鼠肝癌进行超声（1MHz，2W/cm²，5分钟）照射。KDR-tk基因转移后，注射更昔洛韦（GCV）10天，然后每4天测量肿瘤直径直至28天。观察荷瘤小鼠的存活情况。PCR分析和免疫组化测量显示转染基因的表达。采用转移酶介导的dUTP缺口末端标记染色检测凋亡细胞。
与单纯超声治疗组相比，超声联合SonoVue治疗的KDR-tk基因治疗抑制了肿瘤生长，延长了荷瘤小鼠的存活时间；超声和SonoVue介导组的微血管密度明显低于单纯超声组（12.3±1.4对27.4±3.2，P<0.05）。与单纯超声治疗组相比，超声和SonoVue治疗组的凋亡指数增加（25±3.6对36±3.8，P<0.05），而单纯SonoVue介导组与单纯磷酸盐缓冲液组之间无显著差异（17±1.8对14±1.2，P>0.05）。
微泡造影剂增强超声照射介导的基因治疗可能成为持续性HCC的一种新治疗选择。
