Figure 4. Cell Cycle assay.

5 × 10⁵ of MDA-MB-231 or MCF-7 cells were treated with 5 μM SAHA or combining with 100 ng/ml TRAIL 24 hours as described above. After treatment with 5 μM SAHA or combining with 100 ng/ml TRAIL as described above. The harvested cells were centrifuged at 300 g for 5 minutes. While mixing and resuspending cells, cells were slowly added with 1ml of ice cold 70% ethanol and incubated overnight at −20 °C. 10 μl PI was added to the cell suspension. Samples were filtered through 200-mesh filters and then analyzed on BD FACS Calibur flow cytometer. The DNA content of the cells was analyzed for the percentage of cells in G₁, S and G₂/M phase. (A) MDA-MB-231 cell, (B) MCF-7 cell.