重组Canstatin蛋白联合氟尿嘧啶治疗裸鼠结肠癌移植瘤的实验研究

Efficacy of recombinant canstatin protein plus fluorouracil in treatment of colon cancer

目的探讨血管生成抑制剂Canstatin与细胞毒药物氟尿嘧啶（5-FU）联合应用治疗结肠癌的效果,以期探索结肠癌治疗新途径。方法结肠癌SW-480细胞（1×107/只）注射到30只裸鼠皮下,建立结肠癌皮下移植瘤模型。当肿瘤长至2--3 mm时,随机分6组。给药途径均为腹腔注射给药。治疗期间,定期用圆规和游标卡尺测量皮下移植瘤大小。疗程结束时,取下瘤体,常规病理切片,观察药物毒性反应,CD31免疫组化染色,检测肿瘤内微血管密度（MVD）。结果①各试验组肿瘤的生长明显受到抑制,瘤体质量明显低于对照组（P〈0.01）。5-FU＋Canstatin组低、高浓度联合治疗组抑瘤作用较对照组明显增强（P〈0.05）,其瘤重抑制率分别为74.76%和82.04%。②免疫组化：5-FU＋Canstatin组低浓度组（22.6±3.6）和5-FU＋Canstatin组高浓度组（15.0±2.8）治疗小鼠肿瘤组织内MVD显著低于对照组（36.4±5.6）和5-FU治疗组（31.2±4.0）（P〈0.05）,而5-FU治疗组与对照组间差异无统计学意义;③不良反应：各实验组未观察到明显毒性反应。结论重组人Canstatin蛋白能有效抑制人结肠癌生长,无明显毒副作用,为结肠癌治疗提供了新的有力的治疗方法。

Objective To study the anti-tumor effects of recombinant eanstatin protein plus 5-fluorouraeil （5-FU） on colon cancer in order to develop a new treatment modality. Methods Tumor xenografts were established by subcutaneous inoculation of 1 × 10^7 SW-480 colon cancer ceils into the right flanks of 30 nude mice. When the tumors reached 2 -- 3 mm in diameter, mice were randomly divided into 6 groups. All the agents were injected intraperitoneally. During the treatment, the subcutaneous tumors were measured by compasses and caliper every 3 or 4 days. At the end of the experiment, all the tumors were resected and both routine pathological and immunohistoehemieal staining examinations were performed to observe the drug toxicity and intratumoral microveseular density（MVD）. Results ①In every treatment group tumor growth was suppressed significantly. Intraperitoneal injection of eanstatin low-close group, eanstatin high-dose group ,5-FU group, 5-FU group ＋ lowdose eanstatin group,5-FU group ＋ high-dose eanstatin group resulted in a significant inhibition of the growth of SW-480 in vivo compare with that of control group （P 〈 0. 05 ）. The anti-tumor effect of eanstatin plus 5-FU was significantly suppressed the tumor growth. At the end of the experiment, the size of tumors in combination group was the lowest（ P 〈 0.05 ） ,with the highest tumor suppression rate of 74.76% and 82.04%.② The immunohis- toehemieal examination showed that the MVD 5-FU group ＋ eanstatin low-dose group （22.6 ± 3.6 ） ,5-FU group ＋ eanstatin high-close group （ 15.0 ± 2. 8 ） was significantly lower than that in NS group （ 36. 4± 5.6 ） or 5-FU group（31.2 ±4. 0） （P 〈0.05 ）. No significant difference was found in MVD between 5-FU and control groups. ③During treatment, no obvious toxicity was observed. Conclusion Recombinant human eanstatin protein effectively retards the growth of colon cancer through inhibiting the angiogenesis of tumors, without remarkable ad- verse effects. Synergie anti-tumor effect is achieved as eanstatin is combined with eytotoxie drugs.