Figure 2.

Overexpression of p120ctn slows down HT-29 cell proliferation. A, HT-29 GFP and HT-29 GFP-p120ctn cells were cultured for 120 h and observed under phase-contrast microscopy. Bar, 50 μm. B, HT-29 GFP and HT-29 GFP-p120ctn cells were seeded at 2 × 10⁴ cells per well, grown for the indicated times and living cells, then counted using trypan blue solution. Points, mean of three independent experiments; bars, SE. C, BrdUrd incorporation assay. BrdUrd (5 μmol/L) was added for 15 min to the culture medium of 24-h precultured HT-29 GFP (dark gray line) or HT-29 GFP-p120ctn (gray line) cells. After fixation and BrdUrd immunostaining, positive cells were counted using a Becton Dickinson Facstar flow cytometer. Control cells non–treated with BrdUrd were used as negative control (black line). D, top, HT-29 GFP (left) or HT-29 GFP-p120ctn (right) cells were synchronized at G₁-S transition with aphidicolin (5 μg/mL, 24 h) and released in fresh medium for the indicated time. DNA content was then analyzed by FACS after propidium iodide staining. Bottom, histograms indicate the percentage of cells in G₁, S, and G₂-M phases. Asy, asynchronized.