人γ-干扰素基因修饰的结肠癌细胞瘤苗的抗肿瘤作用

Anti-tumor effect of colon cancer cell vaccine modified by human interferon-gamma

目的研究人γ-干扰素(human interferon-γ,huIFN-γ)基因修饰的结肠癌细胞瘤苗的成瘤性及抗肿瘤作用。方法用逆转录病毒质粒pL(IFN-γ)SN将人IFN-γ基因转导入鼠结肠癌细胞株CT26中,用G418进行筛选,得到抗性克隆CT26／IFN-γ,比较CT26／IFN-γ与野生型CT26的成瘤性,评价CT26／IFN-γ对野生型CT26细胞肝转移模型的治疗作用。结果CT26／IFN-γ能在含0．6 g·L-1 G418的培养液中稳定生长;RT-PCR证实IFN-γ基因在CT26／IFN-γ中表达;CT26／IFN-γ细胞能分泌人IFN-γ,体外培养体系中产量为3．5 fg·cell-1·d-1;CT26／IFN-γ的成瘤性比野生型CT26差[Balb／c小鼠肿瘤体积分别为(480±138)mm3与(991±176)mm3,F=31．29,P=0．000]; CT26／IFN-γ对野生型CT26的肝转移亦有明显抑制作用,荷瘤小鼠存活期明显延长(P=0．000)。结论人IFN-γ基因修饰的结肠癌细胞瘤苗有一定的抗肿瘤作用,值得进行深入研究。

Objective To investigate the anti-tumor effect of colon cancer cell vaccine modified by human interferon-γ. Methods A murine colon cancer cell vaccine CT26/IFN-γ was established by gene modification using retrovirus plasmid pL（IFN-γ） SN, the tumorigenicity and effect of the cancer cell vaccine on colon cancer liver metastasis model was evaluated. Results CT26/IFN-γ was established successfully. It grows stably in a medium containing 0. 6 g · L^-1 G418. IFN-γ gene expression in this mutant was confirmed by RT-PCR. This mutant secreted huIFN-γ with a yield of 3.5 fg · cell^ - 1 γ· d ^- 1 in cultured medium. The volume of tumors from this mutant （480 ± 138 mm^3 ） was less than that from wild-type one （991 ± 176 mm^3 , F = 31.29, P = 0. 000 ） when tumor cells were inoculated into a Balb/c mouse model subcutaneously. CT26/IFN-γ impeded tumor progress and prolonged the survival time in CT26 cell liver metastasis model （ P = 0. 000 ）. Conclusion The murine colon cancer cell vaccine modified by human interferon-γ presents anti-tumor effect to some extent.