Figure 3.

Knockdown of PARP-1 induces cell apoptosis and G₀/G₁ arrest in U2OS cells in vitro. Control and transfected cells were seeded at 5 × 10⁴ per well in 96-well plates. (A) Cells were harvested at 48 h and stained with propidium iodide (PI), and then quantified for the cycle distribution by flow cytometry. (B) Western blot analysis of cyclin D1 protein expression in transfected cells. (C) Flow cytometry analysis with annexin V/PI staining was performed to evaluate the percentage of apoptotic cells. (D) Western blot analysis of caspase 3, Bax, and Bcl-2 protein expressions in transfected cells. Data are shown as means ± SD of three independent experiments. *p < 0.05, **p < 0.01.