2.9. Cell Cycle Analysis
SUDHL4 cells were treated with WK500B for 24 h. Then, the cells were harvested, washed with PBS and fixed with cold 70% ethanol at 4 °C for 12 h. Subsequently, the cells were washed twice with PBS and incubated with 50 µg/mL propidium iodide and 10 µg/mL RNase for 30 min in the dark at room temperature. Cells were stored at 4 °C until analysis by flow cytometry (FACS Calibur, BD Biosciences).