A Potential Role for Green Tea as a Radiation Sensitizer for Prostate Cancer.

Prostate cancer (PCa) is the most common non-cutaneous cancer in the United States. There is currently a lack of safe and effective radiosensitizers that can enhance the effectiveness of radiation treatment (RT) for Pca. Clonogenic assay, PCNA staining, Quick Cell Proliferation assay, TUNEL staining and caspase-3 activity assay were used to assess proliferation and apoptosis in DU145 Pca cells. RT-PCR/IHC were used to investigate the mechanisms. We found that the percentage of colonies, PCNA staining intensity, and the optical density value of DU145 cells were decreased (RT/GT vs. RT). TUNEL + cells and the relative caspase-3 activity were increased (RT/GT vs. RT). Compared to RT, the anti-proliferative effect of RT/GT correlated with increased expression of the anti-proliferative molecule p16. Compared to RT, the pro-apoptotic effect of RT/GT correlated with decreased expression of the anti-apoptotic molecule Bcl-2. GT enhances RT sensitivity of DU145 by inhibiting proliferation and promoting apoptosis.