基因-病毒治疗系统CNHK200-hA的构建及对结肠癌治疗作用的体内研究

目的:构建一种结合抗肿瘤新生血管生成的基因治疗与病毒治疗优势的新型肿瘤基因-病毒治疗系统CNHK200-hA,初步研究其在体内对结肠癌的治疗作用. 方法: 克隆人抗血管生成基因Angiostatin(k1-5),命名为hA. 利用病毒重组技术将hA插入肿瘤特异性增殖型腺病毒和非增殖型腺病毒的病毒基因组中,通过动物试验观察其对结肠癌的体内治疗作用. 结果: 构建了一种新型的基因-病毒治疗系统CNHK200-hA. 动物体内试验显示基因-病毒治疗系统CNHK200-hA能在结肠癌HT-29内高效表达K1-5蛋白,使肿瘤内血管明显减少,对结肠癌的疗效明显好于非增殖型腺病毒Ad-hA及肿瘤增殖型病毒ONYX-015. 结论: 插入了抗肿瘤新生血管生成基因hA的基因-病毒治疗系统CNHK200-hA在体内对结肠癌的治疗作用较非增殖病毒Ad-hA及肿瘤增殖病毒ONYX-015进一步提高.

Establishment of a gene-viral therapeutic system CNHK200-hA and its anti-tumor effect on colon cancer

AIM: To develop a novel gene-viral therapeutic system CNHK200-hA, which combines the advantages of the gene therapy, antiangiogenic therapy and virus therapy, and to observe its effect on colon tumor. METHODS: The antiangiogenic gene, designated human angiostatin (k1-5, hA), was inserted into the genome of the replicative and replication-defective adenovirus specific for the tumor cells by virus recombination technology. The expression of the antiangiogenic gene of hA(k1-5), the inhibitory effect to angiogenesis and the curative effect to colon cancer were observed respectively by tumor study in mice. RESULTS: A new kind of gene-viral vector system, designated CNHK200-hA(k1-5), in which the E1b55,000 gene was deleted but the E1a gene of adenovirus was preserved, constructed. The novel vector system possessed the same property as the replicative virus ONYX-015, replication and proliferation in the P53- tumor cells but not in the normal cells, thus specifically killing the tumor cells. Besides, it carried hA(k1-5), further enhancing the effect of anti-tumor. When carrying the gene of hA(k1-5), it introduced the expression of this gene in tumor cells far more effectively than the adenovirus vector employed in the traditional gene therapy. The assay in vivo showed the CNHK200-hA(k1-5) expressed antiangiogenic gene in HT-29 cells, inhibited angieogenesis in tumor and killed the HT-29 cells more effectively than control group. In comparison of the curative effect of the CNHK200-hA(k1-5) on colon cancer with that of ONYX-015 and Ad-hA(k1-5), the difference was significant. CONCLUSION: CNHK200-hAngio(k1-5), a novel vector in which the hA is inserted can increase the expression level of hA. It possesses all the advan- tages of gene therapy, virus therapy, and antiangiogenic therapy, thus further enhancing the curative effect and overcoming such disadvantages as low transfer rate, low expression, lack of target tropism and low anti-tumor activity.