GA exhibited cytotoxicity on HeLa cells.
A, Chemical structure of gambogic acid (GA). B, Effects of GA on viability of HeLa cells. Cells were treated with 0.3125, 0.625, 1.25, 2.5, 5 and 10 μm GA for 24, 48, or 72 h and cell viability was determined by MTT assay. Data were statistical results of three independent experiments (n = 3, mean ± S.E.). C, GA induced G2/M cell cycle arrest in HeLa cells after 24 h treatment. Representative DNA histograms of HeLa cells obtained by flow cytometry analysis. D, Statistical analysis results of percentage of HeLa cells in different cell cycle phases after treated with GA at different doses for 24 h (n = 3, mean ± S.E.). E, GA induced apoptosis in HeLa cells after 24 h treatment. Apoptotic cells were quantified by double supravital staining with Annexin V-FITC and PI. Images were representative results of flow cytometry analysis. F, Statistical analysis results of percentage of apoptotic cells after treated with GA at different doses for 24 h (n = 3, mean ± S.E.).