Modulation of radiosensitivity of DU145 prostate carcinoma cells by simvastatin

Purpose To investigate antiproliferative effects of simvastatin in combination with ionizing radiation on DU145 prostate cancer cells and its influence on cellular HMG-CoA-reductase levels. Methods Proliferative responses of DU145 cells were estimated by means of a clonogenic assay or the crystal violet procedure. HMG-CoA-reductase levels were measured by western blot analysis. Results The antiproliferative effects of simvastatin and radiation are dependent on simvastatin dose, radiation dose and treatment time. In vitro treatment of DU145 cells with simvastatin induced HMG-CoA-reductase levels. Conclusion Ionizing radiation more profoundly reduces proliferation as compared to simvastatin exposure, while the combined application of both modalities is synergistic. The inhibition of CoA-reductase may contribute to these effects.