联合转染HSV-tk与IL-2 TNF-a基因对荷人喉癌小鼠作用研究

Head and neck cancer comprise more than 4% of all human cancers worldwide.When detected early,many of these cancers areb treated with either surgery or radiotherapy without significant sequelae.Alternative methods of treatment are therefore needed to reduce treatment morbidity and increase patient survival.A promising new direction fot treatment of tumors in suicide gene therpy.Laryngocarcinoma is particularly well suited to studying this new therapeutic approach because the tumors are readily accessible ,allowing direct and repeated intratumoral administration of drugs and objective momitoroing of tumor responses.To determine if fusion genes of HSV-tk gene and cytokine gene have synergy on the cell killing of the Hep-2 cell lines in vitro and tumor inhibition in vivo. Different fusion genes expressing vectors PL(TI)SN, PL(TT)SN and PL(TK)SN were generated by recombinant DNA technology. Hep-2 was infected by the recombinant retrovirus. The positive clones were obtained after G418 selection and were termed Hep/TI, Hep/TT and Hep/TK respectively. The integration and expression of fusion genes in Hep-2 cells were identified by RT-PCR and Southern blot. The growth state and GCV killing effect of fusion genes modified cells were used to investigate the expression of fusion genes and antitumour effect on Hep-2 cells. RT-PCR and Southern blot analysis confirmed the integration and expression of fusion genes in Hep-2 cells. There was no significant difference in cell proliferation between the Hep/TI and Hep/TK,but the growth of Hep/TT was restrained. After the treatment of GCV the Hep/TI, Hep/TT and Hep/TK all showed high sensitivity to GCV. The killing effect of GCV on Hep/TT was the most siginificant and bystander effects were observed siginificantly in vitro. All these results approved that the fusion genes of Hsv-tk and cytokine gene have synergistic effects on killing Hep-2 cell after treatment of GCV in vitro,which might have therapeutic potentials for laryngocarcinoma.In the tumor bearing mice inhibition experiment,mice received combined therapy developed tumors more slowly and survived much longer when compared with mice only treated with PL(TK)SN.In the treatment groups ,profound anti tumor effects were observed in tumors derived from Hep/TT and Hep/TI cells and the tumor inhibition was significantly better than Hep/TK groups.Consequently combination therapy with IL-2 or TNF-αgene and HSV-tk gene/GCV is effective for laryngocarcinoma.

单独转染胸苷激酶、(HSV-tk)、白细胞介素2(IL-2)和肿瘤坏死因子(TNF-a)基因对人恶性肿瘤有一定的治疗作用，但因各自的缺点而使应用受限制。利用自杀基因与细胞因子基因治疗的作用互补性原理，构建HSV-tk IL-2与TNF-a单独与联合的载体，分别导入荷人喉癌裸鼠密瘴袈逦?GCV)进行治疗，检测多种抑瘤生物效应指标，探索能产生最大抑瘤生物效应又能减少对机体不良反应的组合及相互作用机理，为喉癌的治疗寻找一条新的有效途径。