Cell cycle analysis and apoptosis assay

Annexin V-fluorescein isothiocyanate (FITC)/Propidium iodide (PI) double staining kit (BioVision Research Products, USA) was used to identify the cells in different phases. HeLa cells were treated with Paclitaxel (112.5 µg/ml), Carboplatin (323.5 µg/ml), Gallic acid (312.5 µg/ml), Mix. 1 (Paclitaxel (112.5 µg/ml) + Carboplatin (323.5 µg/ml), Mix. 2 (Paclitaxel (112.5 µg/ml) + Gallic acid (312.5 µg/ml), Mix 3 (Carboplatin (323.5 µg/ml) + Gallic acid (312.5 µg/ml), Mix 4 (Paclitaxel (112.5 µg/ml) + Carboplatin (323.5 µg/ml) + Gallic acid (312.5 µg/ml) for 24 h. After incubation, cells were harvested from the treated and normal samples. The cells were then resuspended in 500 μl of binding buffer, and then 5 μl of annexin V-FITC and 5 μl of PI were added in the dark for 5 min. The cell cycle distribution was then detected by flow cytometry (BD FACSCalibur, India).