FIGURE 6.

PCI-34051 delays cell cycle progression in a concentration-dependent manner. MCF7 cells were synchronized to G₁-S phase by double thymidine block and released in the presence of different concentrations of PCI-34051 for the indicated time points. Cells were fixed, stained with propidium iodide, and cell cycle distributions were assessed by flow cytometry. Data were processed using the FlowJo software (version 9.7). A, schematic of the experiment design used for synchronizing cells to G₁-S phase by double thymidine block and release. B, histograms of flow cytometry analyses showing fluorescence intensity on the x axis and cell counts on the y axis. DNA content analyses of vehicle-treated control cells and PCI-34051-treated cells are presented from 0, 2, 4, 6, 8, 10, 12, 24, and 36 h, post-treatment. Lines are shown for ease of comparison of gated cell populations between G₁ and S/G₂-M phases of vehicle-treated control and PCI-34051-treated cells.