Figure 1. Overexpression of EL and LMW-E impair G2-M transition differently.

A, pTRE-EL and B, pTRE-LMW-E MCF-7 cells were synchronized at the G1/S transition by aphidicolin block, induced for cyclin E expression with doxycycline (Dox, 1μg/ml) for 24 h, released for the indicated times and analyzed by flow cytometry. The graphs show the percentages of cells in the G0/G1, S, and G2/M phases. Right panel, results are normalized to the percentage of uninduced cells in G2/M. Each bar indicates the percentage of cells in G2/M relative to control cells +/- SD (standard deviation) obtained from seven independent experiments. C, D, Representative western blot analysis of cell lysates described in A and B using specific antibodies against cyclins E, A, and B, and vinculin. Changes in cyclin B expression is as percentage of control after densitometry of uninduced and induced cells (*P < 0.05).