Treatment with 5-Fluoruracil (5-FU) doesn't alter Cdt1 protein expression levels in HeLa or HepG2 cells.

<p>Asynchronous HeLa (A) and HepG2 cells (C) were incubated with 5-FU (0.1 and 100 µg/ml) in the presence of BrdU (20 µM, for 1 h). Cells were subjected to immunofluorescence using antibodies against Cdt1, Cyclin A and BrdU. DNA was visualized with DAPI or Hoechst 3258. The percentage of HeLa (B) and HepG2 (D) cells expressing Cdt1, Cyclin A and BrdU in presence of 5-FU, 0.1 µg/ml (grey columns), 100 µg/ml (black columns) and control cells (white columns) is shown; Data are the mean values of the quantifications from at least 3 different experiments from each condition and represent mean ± SD. **p<0.01, ***p<0.001. (E) HeLa and HepG2 cells were synchronized with nocodazole, released to enter G1 phase, and incubated with 5-FU (10 and 100 µg/ml) for 6 hours. Total cell lysates were extracted and subjected to Western blot analysis using antibodies against Cdt1 and Tubulin. Scale bars: A, C, 50 µm.