G-CSF基因治疗配合大剂量化疗抗结肠癌肝转移的效果及其机制探讨

The anti-metastatic effect and activation of peritoneal macrophages by GCSF gene therapy in the colon adenocarcinomabearing mice with liver metastasis

目的：探讨Ｇ－ＣＳＦ基因治疗配合大剂量化疗后的体内抗结肠癌肝转移的效果及其可能的机制。方法：制备Ｃ－２６结肠癌肝转移小鼠模型，观察成纤维细胞介导的腹腔途径Ｇ－ＣＳＦ基因治疗及其配合大剂量５－Ｆｕ后抗结肠癌肝转移的效果。结果：腹腔单独注射大剂量５－Ｆｕ或ｒｈＧ－ＣＳＦ后可明显地抑制Ｃ－２６肝转移结节形成（Ｐ＜０．０５），而腹腔内成纤维细胞介导的Ｇ－ＣＳＦ基因疗法的抗Ｃ－２６肝转移的作用更明显（Ｐ＜０．０１）；配合大剂量５－Ｆｕ后，Ｇ－ＣＳＦ基因疗法抗Ｃ－２６肝转移的效果比单独应用ｒｈＧ－ＣＳＦ或Ｇ－ＣＳＦ基因治疗更明显，且优于ｒｈＧ－ＣＳＦ注射疗法与大剂量５－Ｆｕ联合的治疗效果。经Ｇ－ＣＳＦ基因治疗后小鼠腹腔巨噬细胞吞噬功能、抗原提呈能力、杀伤活性，以及分泌ＴＮＦ、ＮＯ、ＩＬ－１的能力均有明显提高。结论：Ｇ－ＣＳＦ基因治疗配合大剂量化疗可有效地抗结肠癌肝转移，腹腔巨噬细胞功能的增强可能是其机制之一。

Objective: To examine the antimetastatic effect of fibroblastsmediated GCSF gene therapy and highdose chemotherapy on C26 colon adenocarcinomabearing mice and its mechanism. Methods: Experimental liver metastasis model in C26 colon adenocarcinoma mice was prepared by splenic injection of 1×105 C26 cells into BALB/c mouse. Then the tumorbearing mice were injected i.p. with rhGCSF (2 μg/d×14 d) or implanted with 1×107 collagen encapsulated NIH3T3GCSF cells secreting GCSF after gene transfection. Results: The number of liver metastasis was reduced by 5Fu,rhGCSF or GCSF gene therapy, respectively, showing that both rhGCSF and GCSF gene therapy has exact antimetastatic effect and GCSF gene therapy was more effective than rhGCSF injection in vivo. Better results could be observed in C26bearing mice receiving highdose 5Fu after GCSF gene therapy, suggesting that GCSF gene therapy could inhibit the liver metastasis more effectively in C26bearing mice receiving highdose chemotherapy than rCSF injection plus 5Fu and augment the cytotoxicity and the antigenpresenting activity of the peritoneal macrophages significantly. The secretions of IL1,TNF,NO by macrophages were also significantly enhanced. Conclusion: GCSF gene therapy in combination with highdose chemotherapy could inhibit metastasis of colon carcinoma to liver effectively and one of its mechanisms may be the activation of peritoneal macrophages .