Development of multimodal gene therapy for gastrointestinal cancer using in vivo electroporation

制备了一种新的细胞因子基因IL-21和IL-23的全长cDNA。可以证实，通过将这些新的细胞因子基因转导到肿瘤细胞中，可以诱导强大的肿瘤免疫。此外，对于人食道癌裸鼠移植模型，证实了IL-21的抗肿瘤活性。检测了由肿瘤特异性启动子启动子启动的HSV-tk基因的实用性。HSV-tk基因治疗最有趣的效应是旁观者效应，这是一种允许杀死未转导细胞的现象。通过利用中期因子的最小启动子区域驱动HSV-tk基因，并通过体内电穿孔将IL-21DNA导入肿瘤，这种联合策略产生了一种安全性更高的高效基因治疗方法，体内电穿孔增加了这种有效性的局限性，临床应用范围变得狭窄。抗癌基因d-…体内电穿孔的临床研究到目前为止，更多的地毯仅用于皮下肿瘤。在此基础上，研制了一种可在纤维内窥镜下使用的新型电极，在开胸或剖腹下活体电穿孔于猪的食道或肝脏不产生生理效应，且操作安全。这些结果导致了临床应用。对既可在纤维内窥镜下使用又可在镜下操作的电极进行了改进。目前，正在准备专利申请。至于与基因转移的结合，预计会有很高的基因表达，因此组蛋白脱乙酰基转移酶抑制剂(FK226)可能会增强转基因基因的转录。其中一个抑癌基因是由FK226诱导的，我们证实了该基因在人食道癌细胞中显示了抗肿瘤活性。分析FK226体内电穿孔对细胞因子基因抗肿瘤作用的增强作用和对疫苗的作用。较少

The preparation of cDNA of interleukin-21 and-23 which is a new cytokine gene was done. It could confirm that powerful tumor immunity was induced by transducing these new cytokine genes to the tumor cells. And, as for human esophageal cancer transplantation model as well which a nude mice was used for, the effect on an anti-tumor activity of IL-21 was confirmed. The utility of the HSV-tk gene which is promoted by tumor specific mini-promoter was examined. The most interesting effect of HSV-tk gene therapy is the by-stander effect, a phenomenon allowing the killing of untransduced cells. By using the minimal promoter region of midkine to drive HSV-tk gene, and in vivo electroporation to transduce the IL-21 DNA into the tumors, this comibination strategy produces an efficient gene therapy with improved safety.in vivo electroporatio under the view adds a limitation to that utility and clinical application range gets narrow. The clinical trials of in vivo electroporation using anticancer d … More rugs until now was used for is limited to the subcutaneous tumor. Therfore the new electrode which could be used under the fiberscope was developed, in vivo electroporation to the esophagus or the liver under thoracotomy or laparotomy in swine model didn't give it a physiological effect and it could be carried out safely. These results caused to clinical application. The electrode which could be used by fiberscope or under the scopic operation was improved. And that prototype was completed.At present, an application for a patent is being prepared.As for the combination with the gene transfer, a very high gene expression is expected so that histone deacethyl taransferase inhibitor (FK226) may strengthen the transcription of the transfected gene. One of the tumor suppressor genes was induced by FK226, and we confirmed that effect on an anti-tumor activity was shown in the human esophageal cancer cells. It will be analyzed about the reinforcement action of the effect on an anti-tumor of cytokine genes and the effect on vaccine by the combination of in vivo electroporation using FK226. Less