Cell cycle assay
AnnexinV- FITC/PI probe was used
to evaluate the cell cycle. Briefly, the cells were treated with PA
and/or different concentrations of samples. After 24 h incubation, the
cell medium was discarded, and the cells were washed thrice with
pre-cooled PBS. The cell pellet was suspended in a binding buffer, and
then continuously stained with PI and Annexin V-FITC for 15 min in the
dark. The samples were analyzed within 1 h after staining. The cells
were measured by a Cyto FLEX flow cytometer (Beckman Coulter Company,
USA).