The effect of ART on the apoptosis and cell cycle progression of HeLa xenografts. (A) Representative TUNEL assays showing apoptosis in HeLa xenografts(magnification, × 400). (B) Percentage of TUNEL-positive cells per field are expressed as means ± SEM. *P < 0.05, compared with radiation alone group. (C) The cell cycle distributions of the xenografts were analyzed. Values shown are the mean ± SEM. (D) Western blot analysis of Cyclin B1, Cdc2 and Wee1 in the HeLa xenografts.