FIG. 5.
Expression of p21 causes cell cycle arrest in BC-3 cells. BC-3 cells stably expressing a lentiviral vector allowing the inducible expression of p21 [p21(ORF)] or the parental vector (TRIPZ) were plated at equal densities and, 24 h later, treated with 1 μg/ml Dox for 24 h. The cells were labeled with 25 μM BrdU for 30 min. (A) Cells were analyzed for p21 expression by Western blotting. β-Actin served as a loading control. (B) Cells were fixed and stained with anti-BrdU-FITC antibodies and propidium iodide and analyzed using flow cytometry. One representative experiment (out of 3 independent experiments) is shown. The statistical analysis of all 3 replicates showed that, compared to untreated cells, in Dox-treated p21(ORF)-transduced cells, 32% ± 5% as many cells were in S phase and 176% ± 25% as many were in G1 phase (±SD).