中文摘要：

背景与目的：研究PTEN缺失细胞中活性氧（ROS）水平、DNA氧化损伤和抗氧化能力的变化。材料与方法：运用化学／荧光发光分析、免疫细胞化学、中性单细胞凝胶电泳技术，分别比较Pten^＋/＋MEFs与Pten^-/-MEFs细胞中ROS、8-羟基脱氧鸟苷（8-OH-dG）水平、DNA双链断裂（DSBs）以及抗氧化能力的差异。结果：Pten^-/-MEFs细胞中ROS、8-OH-dG水平明显增高，DSBs增加，抗氧化能力减弱。结论：PTEN可能通过调控细胞内ROS水平拮抗DNA氧化损伤。

英文摘要：

BACKGROUND AND AIM： To study the variation of the level of reactive oxygen species（ROS）, oxidative DNA damage and antioxidative ability between Pten ＋/＋MEFs and Pten-/-MEFs cells. MATERIALS AND METHODS： Fluorescence activated cell sorter（FACS）, immunocytochemistry （ICC） and neutral single cell gel electrophoresis（SCGE） were employed to compare the differences of the levels of ROS , 8-hydroxy-2＇ -deoxyguanosine（8-OH-dG）, double-strand breaks（DSBs）and antioxidative ability between Pten ＋/＋MEFs and Pten -/-MEFs cells. RKSULTS： In Pten -/-MEFs , the levels of ROS, 8-OH-dG and DSBs were increased. Moreover, its antioxidative ability was decreased. CONCLUSION： PTEN could regulate the level of ROS to affect oxidative DNA damage.