Effects of resveratrol (RSV) and ionizing radiation (IR) on prostate cancer cell cycle progression and expression of cycle regulators. A. 22RV1 cells were pre-treated or not with RSV (5 μM) for 1 hour followed by treatment with 8 Gy IR. Cells were allowed to cycle for 48 hours after which they were fixed, treated with a triton-X and stained with propidium iodide (PI) solution as described in Methods. Shown are representative results of 3 independent experiments. Pie charts illustrate the proportion of cells in each phase of cell cycle. B. 22RV1 and PC3 cells were pre-treated with RSV (5 μM) for 1 hour followed by 8 Gy IR treatment. Cells were lysed 1 hour after IR exposure and subjected to immunoblot analysis using antibodies against the indicated cell cycle markers. Shown are representative immunoblots of 3 independent experiments.