Fig. 7.

p53 is required for the PDMF-driven G₂/M cell cycle arrest and apoptosis induction in A549 cells. a and b Knockdown of p53 completely abolishes the PDMF-mediated G₂/M cell cycle arrest. Proportion of cells at G₂/M phase upon p53 knockdown and 24 h incubation with PDMF (75 μg/ml) or doxorubicin (580 ng/ml, positive control) was analyzed by flow cytometry and quantified. c and d PDMF-induced apoptosis is substantially abrogated upon siRNA knockdown of p53. Apoptotic cells in p53-silenced and PDMF-stimulated A549 cells were analyzed by flow cytometry, and total annexin V-positive cells were quantified. The values are the mean ± SD of three different experiments. ^* P < 0.05 indicates a significant difference compared with each No siRNA