To investigate the effect of ginsenoside Rg3 on the activity, apoptosis and proliferation of human breast cancer cell line MDA-MB-231.

Human breast cancer cell line MDA-MB-231 was cultured in vitro and divided into control group (normal culture) and Rg3 treatment group (0.4 mg/ml, 0.8 mg/ml, 1.6 mg/ml). The metabolic activity of cells in each group within 24 h was detected by methyl thiazolyl terazolium (MTT) assay. Apoptosis kit was used to detect the activity of caspase 3 in each group. The morphological changes of cells in each group were observed by electron microscopy. The expression level of cyclin-dependent kinase 2 (CDK2) protein was detected by Western blot. Comparison between the enzymatic activity of caspase 3 and the protein expression levels of CDK2 was conducted using t-test.

Human breast cancer cell line MDA-MB-231 was treated with different concentrations of Rg3, and the cell activity was weakened in a time and dose dependent manner. Upon detection with the apoptosis detection kit, it was found that when the concentrations of Rg3 were 0.4 mg/ml, 0.8 mg/ml, and 1.6 mg/ml respectively, the caspase 3 enzyme activities after treating the cells for 24 hours were (116.00±8.71), (171.00±10.82), and (95.67±5.03) respectively. Only at the concentration of 0.8 mg/ml of Rg3, there was a statistically significant difference compared to the control group (105.33±7.51) (t=8.64, P<0.01). The results of electron microscopy showed that the experimental group with Rg3 concentration of 0.4 mg/ml and 0.8 mg/ml showed typical apoptotic characteristics, while the experimental group with Rg3 concentration of 1.6 mg/ml showed fragmentation. Western blot results showed that the expression level of CDK2 protein in 0.8 mg/ml Rg3 treatment group (0.76±0.03) was significantly decreased compared with that in the control group (0.89±0.07) (t=2.84, P<0.05).

Rg3 with a concentration of 0.8 mg/ml can significantly inhibit the metabolic activity of human breast cancer cell line MDA-MB-231, promote cell apoptosis, reduce the expression of cell proliferation factor CDK2, and have a certain inhibitory effect on cell proliferation.