Liu Xiang, Tian Pei-Kun, Ju Dian-Wen, Zhang Min-Hui, Yao Ming, Cao Xue-Tao, Gu Jian-Ren
National Laboratory for Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai, China.
Cancer Gene Ther. 2003 Jul;10(7):529-39. doi: 10.1038/sj.cgt.7700596.
Based on the fact that aberrant overexpression of some growth factor receptors was observed in a variety of human cancer cells, a novel nonviral gene delivery system GE7, which contains a 16-amino-acid ligand for identifying EGF receptor was constructed for tumor-targeted gene therapy. Intravenous administration of GE7 system revealed that it has the ability to target beta-galactosidase (beta-gal) reporter gene into murine hepatoma (Hepa) cells. Owing to the limited antitumor effects elicited by a single-gene transfer, recent efforts to treat malignancy using combined gene therapy have been accomplished with varying degrees of success. In this study, the human cyclin-dependent kinase inhibitor gene p21(WAF-1) and the murine cytokine gene granulocyte-macrophage colony-stimulating factor (GM-CSF) were used simultaneously for in vivo gene therapy through systemic injection of the EGF R targeted GE7/DNA complex into murine hepatoma-bearing mice. The results demonstrated that combined administration of p21(WAF-1) and GM-CSF could remarkably inhibit the growth of subcutaneously transplanted hepatoma Hepa cells, and significantly increase the survival rate of tumor-bearing mice. The activities of natural killer (NK) cells and specific cytotoxic T lymphocytes (CTL) were clearly enhanced after combined gene therapy. In vitro experiments showed that p21(WAF-1) gene transfer exhibited a suppressive function on the growth of Hepa cells and the expression of H-2K(b) and B7-1 molecules on Hepa cells increased significantly after combined genes delivery. All these results suggested that the GE7 system was able to target therapeutic genes efficiently to cancer cells, which showed high EGF R expression. The cotransfer of p21(WAF-1) and GM-CSF genes apparently inhibited the growth of tumors through (a) the arrest of tumor cell growth and (b) the enhancement of systemic antitumor immunity.
基于在多种人类癌细胞中观察到某些生长因子受体异常过表达这一事实，构建了一种新型非病毒基因递送系统GE7，其包含用于识别表皮生长因子（EGF）受体的16个氨基酸的配体，用于肿瘤靶向基因治疗。静脉注射GE7系统显示它有能力将β-半乳糖苷酶（β-gal）报告基因靶向到小鼠肝癌（Hepa）细胞中。由于单基因转移引发的抗肿瘤作用有限，最近使用联合基因疗法治疗恶性肿瘤的努力已取得不同程度的成功。在本研究中，通过将靶向EGF受体的GE7/DNA复合物全身注射到荷瘤小鼠体内，同时使用人细胞周期蛋白依赖性激酶抑制剂基因p21（WAF-1）和小鼠细胞因子基因粒细胞-巨噬细胞集落刺激因子（GM-CSF）进行体内基因治疗。结果表明，联合给予p21（WAF-1）和GM-CSF可显著抑制皮下移植的肝癌Hepa细胞的生长，并显著提高荷瘤小鼠的存活率。联合基因治疗后，自然杀伤（NK）细胞和特异性细胞毒性T淋巴细胞（CTL）的活性明显增强。体外实验表明，p21（WAF-1）基因转移对Hepa细胞的生长具有抑制作用，联合基因递送后Hepa细胞上H-2K（b）和B7-1分子的表达显著增加。所有这些结果表明，GE7系统能够将治疗性基因有效地靶向到高表达EGF受体的癌细胞。p21（WAF-1）和GM-CSF基因的共转移显然通过（a）肿瘤细胞生长停滞和（b）全身抗肿瘤免疫力增强来抑制肿瘤生长。
