β-榄香烯对兔VX2肾癌放疗增敏作用中Caspase-3及Bcl-2的表达

Expressions of Caspase-3 and Bcl-2 in radiosensitization of β-elemene on rabbit VX2 renal carcinoma

目的:观察β-榄香烯对兔VX2肾癌的放射增敏作用以及Caspase-3与Bcl-2蛋白表达的变化.方法:兔VX2肾癌模型分为空白组、放疗组、放疗+β-榄香烯10mg/kg经肾动脉灌注(增敏组)3组,B超监测肿瘤体积变化.实验结束后提取瘤体标本进行形态学观察.免疫组化法分析Caspase-3及Bcl-2蛋白表达量的变化.结果:10mg/kgβ-榄香烯增敏组肿瘤瘤体生长受抑制,生长延缓时间由(20.91.30)d增至(23.02.13)d(P<0.05).透射电镜观察到不同实验组肿瘤细胞凋亡的超微结构变化.免疫组化法显示Caspase-3及Bcl-2蛋白在各组呈梯度表达.结论:榄香烯对兔VX2肾癌具有放疗增敏作用.它通过Caspase-3途径促进肿瘤细胞凋亡.Bcl-2蛋白表达参与该凋亡途径.

AIM： To investigate whether low-dosage β-elemene can enhance the effect of irradiation on rabbit VX2 renal carcinoma and to observe the expression changes of Caspase-3 and Bcl-2 during the process. METHODS： Experimental rabbits with VX2 renal carcinoma were divided into 3 groups： control, radiation and radiation ＋ β-elemene. 10 mg/kg β-elemene emulsion was infused through the renal artery. The change of tumor＇s volume was measured dynamically by B-ultrasound. Then the tumor tissues were studied comparatively with light microscope and transmission electron microscope. The expressions of Caspase-3 and Bcl-2 were detected by immtmohistochemistry. RESULTS： The tumor＇s volume of radiosensitivity group observed by B- ultrasound was restrained obviously and its Average-waitingtime was prolonged from（20.9 ±1.30） d to（23.0 ±2.13） d（P 〈 0. 05 ）. Different apoptosis were observed under transmission electron microscopy. The expressions of Caspase-3 and Bcl-2 showed gradient among these groups. CONCLUSION： Lowdosage β-elemene could enhance the radiosensitivity of rabbit VX2 renal carcinoma model and promoted the apoptosis through Caspase-3 pathway. It could up-regulate Bax and down-regulate Bcl-2 protein expressions.