中文摘要：

目的：研究PTEN基因在旁效应细胞中的表达变化。方法：采用未照射细胞与直接照射细胞按1：1共同培养，以及将直接照射细胞培养液离心加入未照射细胞中培养形成2种旁效应细胞模型，对比PTEN mRNA及蛋白表达在2种旁效应细胞、直接照射细胞、未照射细胞中的变化。结果：直接照射的PTEN蛋白表达与照射剂量有关，照射剂量越大其下调越为明显；PTEN蛋白表达下调程度与细胞的处理方式有关，以受照细胞培养液培养的旁效应细胞表达下调最为显著，且2种旁效应细胞中PTEN蛋白的表达下调程度均高于直接受照细胞（P〈0．01）。结论：PTEN蛋白表达与低剂量电离辐射生物学效应及电离辐射旁效应的发生发展密切相关。

英文摘要：

Objective：To study the changes of PTEN gene expression in radiation-induced bystander cells. Methods.. The irradiated cells and non-irradiated cells were co-cultured in a ratio of 1 ： 1. The culture medium of irradiated cells was used to culture non-irradiated cells to create two bystander cell models. The expression of PTEN mRNA and protein in the bystander cells, irradiated cells, non-irradiated cells was compared. Results： The protein expression of PTEN in the irradiated cells was negatively associated with the irradiation dose. The down-regulation degree of PTEN protein was related to the different treatments of cells. The most prominent down-regulation was found in the bystander cells cultured with medium of irradiated cells. The down-regulation of PTEN protein in the two kinds of bystander cells was more severe than that in the irradiated cells （P〈0. 01）. Conclusion： PTEN protein expression can be influenced by low dose radiation and the bystander effect of radiation.