Effects of PTN on cell apoptosis and the cell cycle.

<p>(A) The statistical results of PTN on cell apoptosis. The percentage of early apoptotic cells plus late apoptotic cells in the PTN-siRNA-treated group was significantly higher than the controls, indicating that PTN depletion induces cell apoptosis in RPE cells and HUVECs. (B) The statistical data for the cell cycle distributions of NS-siRNA and PTN-siRNA treated groups in RPE cells and HUVECs. PTN-siRNA treatment induces cell cycle arrest in the G0/G1 phase and results in reduced cell numbers in the S phase. Data are presented as the means ± SD and presented in <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115523#pone.0115523.t002" target="_blank">Table 2</a></b>. Each experiment was repeated three times. **P < 0.01.