Novel ginsenoside derivatives have shown their effects on PC-3 cells by inducing G1-phase arrest and reactive oxygen species-mediate cell apoptosis.

In this study, piperazine groups were introduced into ginsenoside to enhance its ability to induce Reactive Oxygen Species (ROS) production and apoptosis in cancer cells. In total, 27 ginsenoside piperazine derivatives were synthesized and tested for their anti-proliferative activity in cancer cell lines by MTT assay. The results showed that compounds 4a, 4g, 4f, 4i, 5g, 5i, 6a, 6g, 6f and 6i had significant inhibitory effects on cancer cell growth. Compound 6g showed the strongest anti-proliferative effect on PC-3 cells with an IC50 of 1.98 ± 0.34 μM. Compound 6g could also induce G1-phase arrest and apoptosis in PC-3 cells, with apoptosis rates of 8.1%, 41% and 56.1% observed at 5, 10 and 20 μM, respectively. Compound 6g also significantly enhanced the intracellular fluorescence of ROS sensitive substrates, with a fluorescence intensity ratio of 23.1% observed in treated cells, indicative of ROS production. Following N-acetylcysteine treatment, apoptotic rates of the cancer cell lines decreased from 38.9% to 7.3%, and the expression of Cl-PARP, Cl-Caspase-3 and Cl-Caspase-9 also decreased, confirming that compound 6g induced apoptosis through ROS induction. Compound 6g also stimulated the translocation of Bax from the cytoplasm to the mitochondria, which enhanced Cytochrome C (Cyt C) release, and increased the expression of the apoptotic markers Cl-PARP, Cl-Caspase-3, and Cl-Caspase-9 in PC-3 cells. Taken together, these data reveal the anti-cancer effects of compound 6g that enhance ROS production, and then induce apoptosis through mitochondrial pathway.