Effect of betulinic acid on the regulation of Hiwi and cyclin B1 in human gastric adenocarcinoma AGS cells.

AbstractAim:To investigate the effect of betulinic acid (BA) on the proliferation, apoptosis and cell cycle of gastric adenocarcinoma cell AGS in vitro and the underlying mechanism.Methods:The effect of BA on the proliferation of AGS cells was measured by using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) assay. Apoptosis was analyzed by using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double-labeled flow cytometry (FCM) and Hoechst 33258 staining. The influence of BA on cell cycle of AGS cells was tested by PI staining. Both FCM and reverse transcription-PCR (RT-PCR) technologies were applied to detect the expression of Hiwi and Cyclin B1.Results:BA exhibited significant cell proliferation inhibition, as well as its potency of inducing apoptosis in AGS cells in vitro in a time- and dose-dependent manner. The IC₅₀ value for 24 h was 18.25 μg/mL (95% confidence interval: 15.16 to 27.31 μg/mL). Cells treated with BA showed increased cell population in G₂/M phase, with decreased S phase population. The expression of Hiwi and Cyclin B1 was down-regulated in BA-treated AGS cells in a dose-dependent manner.Conclusion:BA exerted potent effect on growth inhibition, G₂/M cell cycle arrest and induction of apoptosis in AGS cells in vitro, possibly associated with the down-regulation of Hiwi and its downstream target Cyclin B1 expression. The potent antitumor capacity of BA suggested that it could be a promising new experimental anticancer agent in human gastric adenocarcinoma treatment. [ABSTRACT FROM AUTHOR]