多西紫杉醇的细胞毒性和体外放射增敏作用

Cytotoxicity and radiosensitizing effect of doxtaxol in vitro

目的 :观察新的抗肿瘤药多西紫杉醇 (Doxtaxol)细胞毒性和对体外放射增敏作用。方法 :应用克隆形成分析多西紫杉醇对鼻咽癌细胞的细胞毒性和体外放射增敏作用。放射增敏作用研究采用药物浓度为半数抑制剂量 (ID5 0 )。常规照射剂量 2Gy时的放射增敏比 (SERSF2 )定义为 2Gy时对照存活分数 (SF)和药物处理组SF。 结果 :多西紫杉醇的细胞毒性呈剂量依赖性关系 ,ID5 0 为 3 .2× 10 - 8mg/ml。当 3 .2× 10 - 8mg/ml多西紫杉醇作用 3 ,6,12和 2 4h ,各时间点均可见放射增敏效应。相应的放射增敏比SERD0 分别为 1.2 7,1.44,1.53和 1.58;SERDq分别为 1.40 ,3 .2 0 ,5.0和 7.5;SERSF2 分别为 1.3 8,2 .2 ,3 .0和 3 .4。结论 :多西紫杉醇的细胞毒性呈剂量依赖性 ,对人鼻咽癌细胞系CNE1有明显的放射增敏作用 。

Objective:To investigate cytotoxicity and radiosensit iz ation of Doxtaxol on human nasopharyngeal carcinoma cell line CNE1. Met hods: The cytotoxicity and radiosensitizing of doxtaxol were investigat ed by using clongenic assay on human nasopharyngeal carcinoma cell line CNE1. Th e change in radiosensitivity was quantified by calculating the sensitive enhance ment ratio (SER) at a clinically relevant dose of 2 gray, defined as mean surviv al fraction (SF) for control/mean SF for drug (SER 2Gy ). Results:The cytotoxicity of doxtaxol was in a dose-dependent manner. The 50% i nhibition concentration of doxtaxol was 3.2×10 -8 mg/ml.With 3.2×10 -8 mg/ml doxtaxol exposed to CNE1 cells for 3,6,12, and 24 hours, the correspon ding SER D0 were 1.27,1.44,1.53, and 1.58 , SER Dq were 1.40,3.20, 5.0, and 7.5, SER SF2 were 1.38,2.2,3.0, and 3.4. Conclusion: The cytotoxicity of doxtaxol was in a dose-dependent manner. Doxtaxol ha s a radiosensitizing effect, and radiosensitization is dependent on time.