Figure 6.

Effect of letrozole (0.7 μM) or/and radiotherapy (RT) on MCF-7CA cell-cycle progression. (a) Control cells were compared with (b) MCF-7CA cells harvested after exposure to letrozole. In the case of RT treatment, cells were harvested after RT (c) without or (d) with letrozole. Cells were fixed and stained with propidium iodide for flow cytometry analysis as described in Materials and methods. Percentages of the G₀/G₁ phase, the S phase, and the G₂/M phase were determined by CellQUEST analysis software on the basis of DNA content of the histogram. Data represent mean values of duplicate samples. Similar results were obtained in replicate experiments.