重组可溶性Fas偶联PKC抑制剂对裸鼠结直肠癌移植瘤的杀伤作用

Tumoricidal effect of recombinant soluble Fas coupled with the PKC inhibitor on orthotopic implant of human colorectal carcinoma in nude mice

目的 探讨重组可溶性Fas偶联蛋白激酶C（PKC）抑制剂在裸鼠中对人体结直肠癌细胞的杀伤作用及对癌细胞转移的抑制作用。方法 将多次裸鼠传代的FasL阳性人HR-8348肿瘤组织约0．01g接种于4～5周BALB／c-nu／nu裸鼠盲肠壁，瘤体生长1周后，用随机数字法将裸鼠分为4组，每组12只。实验组（Fas偶联PKC抑制剂＋5-Fu）于第0、4、8、12、16天腹腔注射100μl（3mg／m1）Fas偶联PKC抑制剂＋0．5mg5-Fu。单纯Fas偶联PKC抑制剂治疗组除不给予5-Fu外余同实验组。单纯5-Fu治疗组除不给予Fas偶联PKC抑制剂外余同实验组。空白对照组于第0、4、8、12、16天注射生理盐水100gl。肿瘤种植后1个月拉颈处死各组裸鼠，测量原位种植肿瘤的重量，计算瘤重抑制率、凋亡指数（AI）、肝转移发生率并了解腹水出现情况。结果 对照组、单纯5-Fu治疗组、单纯Fas偶联PKC抑制剂治疗组、Fas偶联PKC抑制剂＋5Fu组的抑瘤率分别为0、43．1％、79．9％、86．3％，腹膜转移率分别为100％、45．5％、16．7％、8．3％，肝转移率分别为75．O％、36．4％、16．7％、0，与对照组比较，后三组结直肠癌的生长和转移受到明显抑制（P〈0．05），尤以Fas偶联PKC抑制剂＋5Fu组最明显。结论 重组可溶性Fas偶联PKC抑制剂对裸鼠结直肠癌移植瘤具有较强的靶向杀伤作用，且与5-Fu具有协同作用。

Objective To evaluate the target killing effect and metastasis prevention effect of soluble Fas combined with PKC inhibitor on the growth of human colorectal carcinoma implant in nude mice. Methods Orthotopic implantation and metastasis model of human colorectal carcinoma was reproduced in nude mice. Tumor tissue of tumor cell line HR-8348 with positive expression of FasL was implanted to the colonic wall of nude mice. After one week of tumor growth, mice were randomly divided into four groups according to the different agents injected into the peritoneal cavity. Twelve mice were in each group. The mice in the combined treatment group （recombinant soluble Fas coupled with PKC inhibitor＋5-Fu） were injected intraperitoneally 100μl （3mg/ml） recombinant soluble Fas coupled with PKC inhibitor and 0. 5 mg of 5-Fu. （On the day of 0, 4, 8, 12 and16）. At the same time, a group of tumor bearing mice were given recombinant soluble Fas coupled with PKC inhibitor only, and another group with 5-Fu only, and in the control group only normal saline was given. One month after implantation, tumor weight, inhibition rate and the presence of metastasis were evaluated respectively after the mice were sac- rificed. Results Compared with control group, the orthotopically implanted tumors were significantly reduced in weight in mice treated with 5-Fu, recombinant soluble Fas coupled with the PKC inhibitor, and combined treatment, with respective inhibited rates of 43. 1%, 79. 9%, and 86. 3%. Liver metastasis was also inhibited with significant decrease in incidence in 5-Fu group, recombinant soluble Fas coupled with the PKC inhibitor, and combined group compared with that in control group （75.0% vs 36.4%, 16.7%, and 0%）. The incidence of peritoneal metastasis was also decreased significantly in 5-Fu, recombinant soluble Fas coupled with PKC inhibitor, and combined treatment compared with that in control group （100% vs 45.5%, 16. 7%, and 8. 3%, P〈0. 05）. The growth and metastasis of human colorectal carcinoma implanted in nude mice were significantly reduced in recombinant soluble Fas coupled with PKC inhibitor and combined group compared with that in 5-Fu group. Conclusion The recombinant soluble Fas and PKC inhibitor can afford strong target killing effect on human colorectal carcinoma in nude mice. Combined with cytotoxic agents, recombinant soluble Fas coupled with PKC inhibitor could be more effective.