外源性PTEN基因稳定转染对SHG44细胞周期和增殖的影响

以PTEN基因真核表达载体体外转染SHG44细胞，筛选稳定转染的细胞克隆并扩增培养，以原位杂交、免疫组化方法检测PTEN基因的表达情况，并研究了PTEN基因对胶质瘤细胞周期、超微结构、生长速率等特性的影响，观察导入人PTEN基因对SHG44细胞裸鼠致瘤能力的影响。结果表明，稳定转染PTEN基因的SHG44胶质瘤细胞中PTEN基因和蛋白均稳定表达，细胞周期明显改变，细胞从G1期到S期发生抑制，细胞超微结构有退行性改变，细胞增殖活性及裸鼠致瘤能力显著降低。提示转染外源性PTEN基因可阻止SHG44胶质瘤细胞由G1期进入S期，并抑制肿瘤细胞增殖。

EFFECTS OF EXOGENOUS PTEN GENE ON THE CELL CYCLE AND PROLIFERATION OF SHG44 GLIOMA CELL

Eukaryotic expression vector containing PTEN gene was transfected into SHG44 cell under mediation of lipofectamine, and positive cell clones were selected and amplified. Expression of PTEN gene was detected by in situ hybridization and immunohistochemistry. Flow cytometry, electron microscope and other methods were adopted to measure the effects of PTEN on cell cycle, ultrastructure, and cell growth of the transfected glioma cells, as well as on tumorigenicity in nude mice. The results showed that PTEN gene and protein were expressed in the glioma cells transfected with PTEN gene. The progression of cell cycle was arrested from G1 to S phase. The growth of cells transfected with PTEN gene in nude mice was dramatically inhibited compared with the parent SHG44 cells. This experiment suggested that the growth of SHG44 glioma cells could be arrested at G1/S phase, and it could be significantly suppressed by exogenous PTEN gene.