中文摘要：

目的 通过人肺腺癌A549细胞株裸鼠移植瘤模型,研究β-榄香烯对移植瘤的照射增敏效应,寻找最佳增敏剂量,并探讨照射增敏机制是否与抑制survivin表达有关.方法 采用细胞悬液接种法建立裸鼠移植瘤模型;将达到0.8～1.0 cm3瘤体积的裸鼠随机分为空白对照组、药物组（25、45和100 mg/kg）和药物＋照射组,每组5只.治疗后瘤体积倍增时观测结束,获得各组的生长曲线.计算2、4、6和8 d各药物组的平均抑瘤率并对体积变化进行比较.通过计算增敏系数,获得最佳增敏剂量.采用增敏剂量的β-榄香烯,应用免疫组织化学染色检测各组survivin的表达.结果 成功建立裸鼠移植瘤模型,根据体积变化获得各组的生长曲线.在2～8 d之间,25、45和100 mg/kg组的平均抑瘤率变化趋势与体积变化规律相一致,β-榄香烯的抗肿瘤作用具有剂量依赖性.EF值分别为0.84（25 mg/kg）、1.24（45 mg/kg）、2.04（100 mg/kg）,最佳增敏剂量为45 mg/kg.药物组对survivin表达影响不大,照射组survivin表达明显增强,联合组survivin表达明显减弱.结论 β-榄香烯有明确的放疗增敏作用,可能通过抑制survivin的表达,达到放疗增敏的作用.

英文摘要：

Objective To explore the effect of β-element on the oadiosensitivity of transplanted tumor, and its relationship with the expression of survivin. Methods The transplanted mice model was established through the cell suspension inoculation. The mice with transplanted tumor size of 0. 8-1.0 cm3 were randomly divided into 8 groups as blank control, 25, 45 and 100 mg/kg group, irradiation group,25 mg/kg ＋ irradiation group, 45 mg/kg ＋ irradiation group, 100 mg/kg ＋ irradiation group. The tumor size was measured every other day until tumor size was double, and the growth curve was obtained. The average tumor growth inhibition rate of β-element and tumor size were attained at 2,4,6 and 8 d after β-element injection. The expression of survivin was detected with immunohistochemistry. Results The nude mice model was successfully established and the growth curves were obtained according to the tumor size.Between 2 and 8 d after β-elemene injection, the variation tendency of the average tumor growth inhibition rate was consistent with the size in β-elemene treatment groups. The antitumor effect of β-elemene was in a dose-dependent manner. The values of radiosensitivity enhancement factor were 0. 84,1.24,2.04 for 25,45 and 100 mg/kg group, respectively ,and the optimal dose was 45 mg/kg. β-element had little effect on the expression of survivin, and the expression of survivin significantly enhanced in irradiation group and decreased in β-element ＋ irradiation groups. Conclusions β-elemene could enhance the tumor radiosensitivity through inhibitiong the expression of survivin.