β-榄香烯对兔VX2肾移植癌的放射增敏作用

目的观察β-榄香烯对兔VX2肾移植癌的放射增敏作用。方法建立兔VX2肾移植癌模型。将动物随机分为空白对照组、放疗组和放射增敏组(放射治疗结合β-榄香烯乳剂肾动脉灌注治疗)。予以各组相应干预措施后,采用螺旋CT及B超动态监测肿瘤体积的变化,比较各组肿瘤生长延缓时间,计算β-榄香烯乳剂的放射增敏比(sensitizationenhancementratio,SER)。同时,观察各组肿瘤组织的病理学改变。采用TdT介导的带生物素dUTP缺口末端标记法检测各组肿瘤细胞凋亡指数。结果采用6MevX线放射治疗(3Gy·Fx-1·d-1×5d)结合β-榄香烯乳剂肾动脉灌注治疗(10mg·kg-1·d-1×5d)的放射增敏组,其肿瘤的放射增敏效应最为显著。放射增敏组肿瘤生长延缓时间明显长于放疗组和空白对照组。β-榄香烯乳剂SER为1.89。透射电镜下放射增敏组肿瘤细胞凋亡较放疗组和空白对照组显著。放射增敏组肿瘤细胞凋亡指数明显高于放疗组和空白对照组。结论低剂量β-榄香烯乳剂对兔VX2肾移植癌具有放射增敏作用,可诱导肿瘤细胞凋亡。

Radiosensitization of β-elemene on VX2 carcinoma transplanted on kidney in rabbits in vivo

OBJECTIVE: To investigate the radiosensitization of beta-elemene on VX2 carcinoma transplanted on kidney in rabbits in vivo. METHODS: The rabbits were all transplanted with VX2 carcinoma on kidney. The appropriate dose of beta-elemene infusion via renal artery for further study on radiosensitization was determined. Then fifty-five rabbits were divided into three groups: untreated group, radiation group and radiation plus beta-elemene-treated group. After corresponding intervention for each group, the tumor volume was measured by ultrasonography and spiral computed tomography. The sensitization enhancement ratio (SER) of beta-elemene was calculated. The pathological change of tumor tissue in kidney was observed by light microscopy and electron transmission microscopy. The apoptotic index was also examined by TdT-mediated dUTP-biotin nick end labeling method. RESULTS: The most significant radiosensitivity was observed in the radiation plus beta-elemene-treated group with 6 Mev X-ray radiation dose of 3 Gy.Fx(-1).d(-1) x 5 d and beta-elemene dose of 10 mg.kg(-1).d(-1). The average time delayed for tumor growth was obviously longer in the radiation plus beta-elemene-treated group than those in the untreated group and radiation group. The SER of beta-elemene was 1.89. The apoptotic index of tumor cells in the radiation plus beta-elemene-treated group was also significantly higher than those in the untreated group and radiation group. CONCLUSION: The beta-elemene can enhance the effects of irradiation on VX2 carcinoma transplanted to kidney in rabbits in vivo by inducing apoptosis of tumor cells.