人脑胶质瘤裸鼠皮下移植瘤模型中血管生成拟态现象的观察

Vasculogenic mimicry in subcutaneous xenograft glioma model of mice

目的观察胶质瘤裸鼠移植瘤生长过程中的血管生成拟态现象（VM）以及与血管内皮依赖性血管之间的关系。方法采用人脑胶质瘤细胞株U87单细胞悬液（2×10^6个／0．1ml）于4周龄裸鼠皮下注射建立移植瘤模型。应用血管内皮细胞标志物CD34和高碘酸雪夫（PAS）试剂双染的方法检测40例不同大小的皮下移植瘤中的VM和血管内皮依赖性血管。结果VM和血管内皮依赖性血管在不同大小的裸鼠皮下U87移植瘤中均存在。微血管密度（MVD）和肿瘤的直径呈正相关（r=0．393，P=0．012），血管生成拟态密度（VMD）与MVD负相关（r=-0．404，P=0．010），而与肿瘤的直径没有显著的相关性（P：0．575）。结论血管生成拟态与内皮依赖性血管是两种不同的肿瘤循环形式，在U87裸鼠皮下移植瘤的生长过程中持续存在并具有互补性，共同为肿瘤的生长提供营养支持。

Objective This study was designed to observe the vasculogenic mimicry （VM）and the relationship between VM and endothelial - dependent vessels during the growth of subcutaneous xenograft glioma in Balb/c mice. Methods Forty 4 - week - old male Balb/c mice were inoculated with a single cell suspension of U87 （2 × 106 tumor cells were injected subcutaneously each mouse）. The VM and endothelial - dependent vessels were detected by dual staining for endothelial marker CD34 and periodic acid - Schiff （PAS）. The density of endothelium -dependent microvessels and VM was measured in tumor tissue sections by 5 randomly selected fields at 200 magnification and the average counts were then calculated. Results Endothelial -dependent vessels as well as VM in xenografts of U87 were persistent exist during the process of tumor growth. With the increase of tumor size, microvessel density （MVD） increased （ r =0. 393, P = 0. 012）, while vasculogenic mimicry density （VMD） was no significant change （P =0. 575）. The VMD were negative correlated with MVD （ r = -0. 404, P =0. 010）. Conclusions There are two microcirculation patterns exist in xenografts of U87 in Balb/c mice during tumor growth, including VM and endothelial - dependent vessels. Both VM and endothelial - dependent vessels provide nutrition and oxygen for tumor development.