Cell cycle analysis of PC-3 cells treated with genistein and radiation. PC-3 cells were treated with either 15 μmol/L or 30 μmol/L genistein for 24 hr, 3 Gy photon radiation, or 15 μmol/L or 30 μmol/L genistein for 24 hr followed by 3 Gy photon radiation. On days 3 and 4 post-radiation, cells were processed for DNA content and cell cycle progression was analyzed by flow cytometry. (Arrow in Fig. 3L): indicates pre-G0/G1 apoptotic peak.