不同剂量γ射线诱发MDM2基因表达初步研究

Preliminary study on the feasibility of MDM2 gene expression level as a radiation biodosimeter

目的观察电离辐射对离体人周围血白细胞中MDM2基因表达的影响。方法采集了3名健康人周围血进行60Coγ射线照射,提取白细胞总RNA,以β-actin作为内对照基因,使用实时荧光定量聚合酶链式反应（Quantitative polymerase chain reaction,qPCR）方法探索辐照后MDM2表达的剂量-效应关系。结果 0~2 Gy剂量范围内,MDM2的mRNA相对表达水平随照射剂量增加而上调,通过拟合建立了0~2 Gy剂量范围内MDM2/β-actin相对表达量与照射剂量间的剂量-效应直线方程（y=1.366 4＋1.112 0x,P〈0.001,相关指数=0.90）。结论电离辐射可以诱发MDM2基因表达发生改变,在0~2 Gy范围内MDM2的mRNA相对表达水平随照射剂量增加而明显上调。

Objective To explore the effect of ionizing radiation on MDM2 gene expression in human peripheral blood.Methods 3 human peripheral blood samples were exposed to 60Co γ-ray at different doses,and its RNA was isolated from white cells.The relative real-time quantitative PCR by standard curve method was set up using β-actin as internal standards.With this method,MDM2 mRNA expression change after ionizing radiation was observed.Results At the dose range of 0~2 Gy,the relationship between the ratio of MDM2 mRNA/β-actin and irradiation dose was fitted to linear correlation.A linear regression equation（y=1.366 4＋1.112 0x,P0.001,R2=0.90） was obtained using statistics regression analysis method.Conclusion γ-Ray can induce changes of MDM2 gene expression and increase dose-dependently at the dose-range of 0~2 Gy.