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

Objective: To investigate the radiosensitization of β-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 β-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 β-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 β-elemene was calculated. The pathological change of tumor tissue in kidey 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 β-elemene-treated group with 6 Mev X-ray radiation dose of 3 Gy · Fx^-1 · d^-1 × 5 d and β-elemene dose of 10 mg · kg^-1 · d^-1. The average time delayed for tumor growth was obviously longer in the radiation plus β-elemene-treated group than those in the untreated group and radiation group. The SER of β-elemene was 1.89. The apoptotic index of tumor cells in the radiation plus β-elemene-treated group was also significantly higher than those in the untreated group and radiation group. Conclusion: The β-elemene can enhance the effects of irradiation on VX2 carcinoma transplanted to kidney in rabbits in viva by inducing apoptosis of tumor cells.