Figure 4

Effect of genistein and radiation treatment on p21 ^WAF1/Cip1 and cyclin B1 expression in PC-3 cells. PC-3 cells were treated with 30 μmol/L genistein for 24 hr then irradiated with 3 Gy photons. Nuclear and cytoplasmic proteins were extracted 1 hr post-radiation. The relative level of (A) p21^WAF1/Cip1 and (B) cyclin B1 protein in 20 μg of nuclear extract was determined by western blot analysis. Data are presented as the mean integrated density value (I.D.V.) of 3 separate experiments (± S.E.M.). (Con): control, untreated-cells; (Rad): cells irradiated with 3 Gy photons; (Gen): cells treated with 30 μmol/L genistein; (Gen + Rad): cells pre-treated with 30 μmol/L genistein for 24 hr then irradiated with 3 Gy photons. Retinoblastoma protein (Rb) was used as a nuclear protein loading control. (*): nuclear value statistically significant from control at p < 0.05; (**): cytoplasmic value statistically significant from control at p < 0.05.