白细胞介素-12基因治疗肿瘤及抑制肝转移

Inhibition of metastatic liver tumor with intravascular IL-12 gene therapy

[目的]探讨经静脉转染表达mIL-12的DNA质粒在肿瘤的治疗及抑制肝转移中的作用.[方法]经皮下和腹腔接种M5076细胞建立荷瘤模型,用水流动力学方法将mIL-12基因转染荷瘤C57BL/6小鼠,观察实验组与对照组的生存率及肿瘤转移灶数目,用ELISA法检测血清中细胞因子水平,用小鼠脾细胞的细胞毒性实验评价CTL和NK细胞活性.[结果]转染pGEG.mIL-12小鼠血清中白细胞介素-12(IL-12)及IFN-γ水平明显升高.经皮下接种肿瘤细胞建立荷瘤模型的转染pGEG.mIL-12小鼠组抑制肿瘤细胞作用、抑制肿瘤细胞肝转移和生存时间与对照组相比较差异均有统计学意义.经腹腔接种肿瘤细胞建立荷瘤模型转染pGEG.mIL-12小鼠组与对照组相比较明显抑制腹腔内肿瘤播散,延长生存时间,差异有统计学意义.M5076细胞对转染pGEG.mIL-12小鼠脾细胞的CTL和NK细胞破瘤细胞活性均不敏感.[结论]用水流动力学方法转染小鼠细胞因子基因产生的高水平IL-12对CTL不敏感的M5076肿瘤有治疗和抑制肝转移的作用.

OBJECTIVE To explore the treatment and the suppression of hepatic metastases efficacy of intravascular administration of plasmid DNA expressing mIL-12.METHODSTo establish tumor models,the M5076 cells were injected into peritoneal cavity or inoculated into the footpad of mice.The hydrodynamics-based transfection was perfomed for transfer pGEG.mIL-12 into C57BL/6 mice.The different survival rate and the number of matastatic foci were observed in experimental and control group animals.The expression of IL-12 and IFN-γ were assayed by ELISA.The activity of NK cells and lymphocyte proliferation from the spleen cells were measured by 51Cr release assay.RESULTSCompared with mice treated with saline or untreated,the significant elevation of the serum concentration of IL-12 and IFN-γ were detected in mice treated with pGEG.mIL-12.The pGEG.mIL-12 transfection drastically suppressed the subcutaneous as well as hepatic metastatic tumors,resulting in significant prolongation of survival period of the animals.Growth of tumor in treated with pGEG.mIL-12 group was significantly inhibited as compared with that in other groups.Transfection with pGEG.mIL-12 also suppressed peritoneal carcinomatosis and prolonged survival time in mice that had been injected with M5076 cells into the peritoneal cavity.The M5076 cells were resistant to CTL and NK cell cytotoxicity.CONCLUSIONThe high level of IL-12 production elicited by the hydrodynamics-based trasfection of the cytokine gene may be quite effective in inhibiting matastatic and CTL-unsusceptible tumor cells.