大鼠C6脑胶质瘤VEGF,MMP-2,MMP-9表达与其MRI相关性的实验研究

目的:运用磁共振成像动态监测大鼠C6脑胶质瘤模型的生长并评价MRI所测某些参数及其与VEGF、MMP-2、MMP-9表达之间的相关性。材料和方法:采用立体定向方法在30只雌性Wistar大鼠右侧尾状核接种C6细胞,并于接种后1周、2周、3周行MR扫描。在各序列图像上测算肿瘤体积、肿瘤强化程度和EI,分析三者之间及其与标本免疫组化结果之间的相关性。结果:24只大鼠荷瘤成功,其MR表现与文献报道相似。随着C6细胞植入时间的延长,肿瘤细胞密度增加并血管生成增多,肿瘤体积增大、强化程度和瘤周水肿程度加重,并且彼此之间呈正相关。VEGF、MMP-2、MMP-9在肿瘤周边表达明显且表达区域相似,VEGF和MMP-9与肿瘤体积、肿瘤强化程度和EI均呈正相关,MMP-2与肿瘤强化程度和EI呈正相关,P<0.05。结论:MRI能够比较清晰的显示大鼠脑胶质瘤的生长,所测肿瘤体积、强化程度和EI之间呈正相关,且与VEGF,MMP-2和MMP-9表达密切相关。

Characteristics and appearances of rat C6 brain gliomas on MRI: correlation with expression of VEGF, MMP-2 and MMP-9

Objective: To investigate the development regularity of rat C6 brain gliomas by MRI and to evaluate the relationship among the calculated MRI parameters of implanted rat C6 brain gliomas and to study correlation between the parameters and expression of VEGF, MMP-2 and MMP-9. Methods: C6 cells were inoculated into the right caudate nucleus of 30 Wistar rats by stereotactic procedure to established animal model. Conventional MRI including enhanced scanning on 1 week, 2 and 3 weeks after implantation were used to dynamically observed the tumor development. Immediately following MRI, some rats were killed for HE and immunohistochemical staining. Then tumor volume, increased enhancement and EI(edema index) were calculated on MRI and performed statistical analysis compared with immunohistochemical changes. Results: The characteristics of rat C6 brain gliomas on MRI were consistent with previous published reports. The tumor cell density and angiogenesis increased with time, and tumor volume, increased enhancement and EI increased simultaneously and correlated positively with each other. Expression of MMP-2 and MMP-9 were observed in 1-week gliomas except VEGF. From then, there were persistent expression of VEGF, MMP-2 and MMP-9. There were positive correlations between the parameters and expression of VEGF, MMP-2, MMP-9. Conclusion: MRI revealed many features of rat C6 brain gliomas progression. There were positive correlations among tumor volume, increased enhancement and EI calculated on MRI, and between the parameters and expression of VEGF, MMP-2 and MMP-9.