白细胞介素18与内皮抑素联合基因导入治疗肿瘤的研究

目的选用白细胞介素18(IL-18)和内皮抑素(ES)联合以物理方法导入治疗肿瘤,以探索一种肿瘤基因治疗的新途径。方法①采用脂质体包被肌肉注射法将作者构建的质粒pSecTag2B- mIL-18和pES1424-mES分别和联合转入Balb/c小鼠,逆转录-聚合酶链反应(RT-PCR)和酶联免疫吸附试验(ELISA)检测两种基因蛋白在动物体内的表达情况;②将小鼠分为4组:pSecTag2B-mIL-18转入组、pES1424-mES转入组、pSecTag2B-mlL-18与pES1424-mES联合转入组和对照组,观察各组肿瘤的生长情况。结果①RT-PCR和ELISA检测证明两种质粒均能够在小鼠肌肉中表达,特别是将两种质粒同时转入同一小鼠肌肉后,能够同时在小鼠肌肉中表达;并将表达的蛋白分泌到外周血液循环中,分泌量与单独基因转入分泌表达量的差异没有统计学意义。②IL-18、ES单独应用都能明显抑制肿瘤的生长,而两基因联合治疗抑制肿瘤的效果明显好于单基因治疗组。结论联合IL-18和ES基因治疗比两种基因单独应用能够更好地抑制肿瘤生长。

A study of new antitumor gene therapy of interleukin-18 combined with endostatin gene

Objective To explore a new method of tumor treatment using interleukin-18(IL-18)com- bined with endostatin to increase effects and decrease side effects of gene therapy.Methods The pSecTag2B- m-IL-18 and pES1424-m-endostatin were constructed by our laboratory,the two naked plasmids were injected into muscle of balb/c mice alone and combined repetitively.The expression status of two genes were tested by RT-PCR and ELISA.In animal experiment,balb/e mice were divided into four groups:endostatin group,IL-18 group,combining group and control group,10~5 of colon26 tumor cells were implanted subcutaneously into every mouse.Two naked plasmids were injected into muscle of balb/e mice alone and combined repectively according to group.The effects of antitumor were observed.Results After transferring of IL-18 genes alone,serum con- centrations of IL-18 were significantly elevated,while interferon(IFN)-gamma also increased in the serum of the mice.After transfection of endostatin gene alone,serum concentrations of endostatin were significantly ele- vated in level of mRNA and protein.When the two plasmids were transferred into muscle of mice simultaneous- ly,IL-18 and endostatin were also expressed simultaneously in both mRNA and protein level as same as trans- ferred alone.In animal experiment,IL-18 and endostatin gene transferring alone resulted in significant suppres- sion of tumor growth respectively,and more significant suppression of tumor growth was observed when the tumor burdening mice were treated by co-transfection with IL-18 and endostatin genes.Conclusion Co-transferring of IL-18 and endostatin gene can be successfully achieved by intramuscular injection of naked plasmids in vivo, more significant therapeutic outcome are observed than single gene transferring of IL-18 or endostatin.