Gallic Acid Induces S And G2 Phase Arrest And Apoptosis In Human Ovarian Cancer Cells In Vitro

Ovarian cancer (OC) is among the top gynecologic cancers in the US with a death tally of 13,940 in the past year alone. Gallic acid (GA) is a natural compound with pharmacological benefits. In this research, the role of GA on cell proliferation, cell apoptosis, cell cycle-related protein expression was explored in OC cell lines OVCAR-3 and A2780/CP70. After 24, 48 and 72 h of GA treatment, the IC50 values in OVCAR-3 cells were 22.14 +/- 0.45, 20.36 +/- 0.18, 15.13 +/- 0.53 mu M, respectively and in A2780/CP70 cells IC50 values were 33.53 +/- 2.64, 27.18 +/- 0.22, 22.81 +/- 0.56, respectively. Hoechst 33,342 DNA staining and flow cytometry results showed 20 mu M GA exposure could significantly accelerate apoptosis in both OC cell lines and the total apoptotic rate increased from 5.34%(control) to 21.42% in OVCAR-3 cells and from 8.01%(control) to 17.69% in A2780/CP70 cells. Western blot analysis revealed that GA stimulated programmed OC cell death via a p53-dependent intrinsic signaling. In addition, GA arrested cell cycle at the S or G2 phase via p53-p21-Cdc2-cyclin B pathway in the same cells. In conclusion, we provide some evidence of the efficacy of GA in ovarian cancer prevention and therapy.