绿色荧光蛋白表达对检测胶质细胞瘤体内侵袭的意义

利用体外转染绿色荧光蛋白基因的胶质瘤细胞大鼠移植瘤模型，研究胶质瘤体内侵袭行为。方法：携有增强型绿色荧光蛋白（ＥｎｈａｎｃｅｄＧｒｅｅｎＦｌｕｏｒｅｓｃｅｎｔＰｒｏｔｅｉｎ，ＥＧＦＰ）基因的ｐＥＧＦＰ－Ｎ３质粒体转染Ｃ６胶瘤细胞，筛选稳定表达绿色荧光蛋白的细胞克隆，并作流式细胞仪和电镜检测，以立体定向法植入ＳＤ大鼠脑实质内建立大鼠移植模型。４周后处死大鼠并作鼠脑连续石蜡切片，相邻切片分别作苏木素－

Detection of brain glioma invasion in vivo by expression of green fluorescent protein

Objective: To determine whether fluorescence from C6 glioma cells transfected with the enhanced green fluorescent protein gene in vitro and xenotransplanted into the brain of SD rats would permit the detection of brain tumor invasion in vivo. Methods: C6 glioma cells were transfected with a plasmid vector (pEGFP-N3) containing the EGFP gene.Stable EGFP-expressing clones were isolated and stereotactically injected into the parenchyma of rats. Four weeks later, rats were killed and continuous brain sections were examined using fluorescence microscopy after adjacent sections were exanined by immunohistochemistry or routine hematoxylin and eosin staining for the visualization and detection of tumor cell invasion. Results: We demonstrate that EGFP-transfected C6 glioma cells maintain stable high-level EGFP expression in the central nervous system during their growth in vivo. EGFP fluorescence clearly demaroated the primary tumor margins and readily allowed for the visualization of distant micrometastasis and local invasion on the single-cell level. Small locally invasive foci, including those immediately adjacent to the leading invasive edge of the tumor, were virtually undetectable by routine hematoxylin and eosin staining and immunohistochemistry. Conclusion: We showed that EGFP-transfected C6 glioma cells can be visualized by fluorescence microscopy after intracranial implantation. This method is superior to routine hematoxylin and eosin staining and immunohistochemistry for the detection and study of relevantpatterns of brain tumor invasion and metastasis in vivo.