Ginsenoside Rh3 Inhibits Proliferation and Induces Apoptosis of Colorectal Cancer Cells.

BACKGROUND: Colorectal cancer is a common malignant tumor of the digestive tract, the morbidity rate of which is rising in recent years. Ginsenoside Rh3 was reported to have anticancer activity; however, the underlying mechanism still needs to be explored in depth. METHODS: Rabbit blood was used to test hemolytic effects of ginsenoside protopanaxadiol (PPD), Rh2, Rh3, and Rg3. Human colorectal cancer SW1116 cells were treated with different concentration of ginsenoside PPD, Rh2, Rh3, and Rg3 in vitro. MTT and TUNEL assay were used to examine cell proliferation and apoptosis. Semi quantitative RT-PCR, immunocytochemistry assay and flow cytometry assay were used to detect the expression of caspase3. RESULTS: The results showed that the inhibiting effects on SW1116 cells of PPD and Rh2 were stronger than those of Rh3 (p < 0.01), but Rh3 had better solubility and slighter hemolytic effects on blood cells than those ginsenosides. Ginsenoside Rh3 inhibited the proliferation of SW1116 cells at 60 μg/mL (p < 0.01), the inhibition effect was increased sharply when the dose of Rh3 was increased from 60 to 120 μg/mL, the inhibition rate was 62.1% at 120 μg/mL, the inhibition appeared at 9 h, and the peak activity occurred at 12 h and maintained until 48 h (p < 0.01). Compared to the control group, the ratio of apoptotic cells, the expression level of mRNA and protein of caspase3 increased in 120 μg/mL Rh3 treated group. CONCLUSION: As a potential anticancer medicine, ginsenoside Rh3 could inhibit the proliferation of colorectal cancer cells in a dose- and time-dependent manner and induce cell apoptosis through upregulating the expression of caspase3.