沙利度胺对小鼠肝脏微小转移瘤血管生长的影响作用研究

目的 探讨应用沙利度胺后小鼠肝脏微小转移瘤内血管的形态学变化规律.方法 20只BALB/c小鼠制成肝转移瘤模型,并将其按体重分层随机方法分为对照组和实验组.从注入结肠癌细胞后第1天开始连续14 d,对实验组小鼠每天腹腔内注射沙利度胺200 mg/kg,对照组小鼠每天腹腔内注射相同剂量的生理盐水.注射后第15天,采用活体荧光显微镜对2组小鼠的肿瘤最大直径在相似范围内的肝脏微小转移瘤(实验组26个、对照组27个)进行活体观察.动物处死后,保留肝脏,采用抗CD34单克隆抗体进行免疫组织化学染色,分别将实验组52个、对照组55个转移瘤按肿瘤最大直径(以400μm为界)分为大小2组,采用t检验比较各组间肿瘤内微血管密度(MVD)、肿瘤内血管分支密度(BD)和肿瘤内CD34阳性血管密度(MVD-CD34).结果 对照组中较大转移瘤的MVD和MVD-CD34分别为(18.1±3.5)%和(22.9±2.8)条血管/高倍视野]高于小转移瘤分别为(13.0±3.2)%和(12.8±2.5)条血管/高倍视野],t值分别为和2.840和9.860,P值均<0.01;而BD差异无统计学意义大、小转移瘤BD分别为(110.0±20.5)和(99.7±17.3)条/lmm2,t=1.040,P＞0.05)].实验组中只有较大转移瘤的MVD-CD34(17.4±2.3)条血管/高倍视野]高于小转移瘤(11.5±2.5)条血管/高倍视野](t=8.770,P<0.01),而MVD和BD差异均尤统计学意义,大、小转移瘤MVD分别为(14.7±3.5)%和(13.2±3.3)%,BD分别为(95.3±18.3)和(97.1±21.O)条/mm2,t值分别为0.826和0.347,P值均>0.05.实验组与对照组间比较,可见小转移瘤的MVD、MVD-CD34和BD差异无统计学意义(t值分别为0.098、1.190和0.392,P值均>0.05),而实验组较大转移瘤的MVD、MVD-CD34和BD均明显小于对照组(t值分别为3.140、9.850和2.870,P值均<0.01).结论 沙利度胺只对具有新生血管的肝脏微小转移瘤表现出抗血管新生作用,而且肿瘤内不同血管成分对抗血管新生治疗反应不同.

The antiangiogenic effect of thalidomide on murine liver metastases

Objective To investigate the morphological change of intratumoral microvessels after administration of thalidomide in the murine hepatic metastases. Methods Among 20 mice with hepatic metastases created by injection of colon-26 tumor cells into the spleen, 10 were treated with thalidomide (200 mg/kg) by intraperitoneal injection daily, the other 10 were treated with saline only by intraperitoneal injection daily. Fifteen days after inoculation of tumor cell, the intratumoral mierovessel of hepatic metastases with similar size in both groups were studied with in vivo microscopy (26 and 27 neoplasms in experimental group and control group respectively ) and immunohistochemistry for CD34 (52 and 55 neoplasms in experimental group and control group respectively). Two-tailed student t test was used to determine differences in intratumoral microvessel density (MVD), intratumoral branch density (BD) and CD34 positive intratumoral microvessel density (MVD-CD34) between the small ( < 400 μm in diameter) and large metastases in both groups, and that between thalidomide treated group and control group. Results For the control group, although the MVD and MVD-CD34 of larger metastases was more than that of small metastases respectively (18.1±3.5)% vs (13.0±3.2) %, t =2.840,P<0.01;(22.9±2.8)vs ( 12. 8±2. 5) vessels per field, t = 9. 860, P < 0. 01 ], the BD was similar to that of small metastases (110.0±20.5)vs(99.7±17.3) branches/rnm2, t = 1.040,P >0.05]. For the thalidomide treated group, despite the MVD-CD34 of larger metastases was more than that of small metastases ( 17.4±2. 3)vs (11.5±2. 5 ) vessels per field, t = 8. 770, P < 0. 01], the MVD and BD was similar to that of small metastases respectively (14.7±3.5)% vs(13.2±3.3) %, t =0.826,P >0.05; (95.3±18.3)vs (97. 1±21. 0)branches/mm2,t=0. 347,P>0. 05]. The MVD, BD and MVD-CD34 of small metastases were similar to each other between two groups ( t = 0. 098, 0. 392,1. 190; P > 0. 05 ), however, that of large metastases were significantly lower in thalidomide treated group than in control group ( t = 3. 140,2. 870, 9. 850;P < 0. 01 ). Conclusions Thalidomide exerts antiangiogenic effect on the hepatic metastases with angiogenesis only, and the different vascular components in the tumor vasculature demonstrate variousresponses to antiangiogenic therapy.