Ginsenosides Rg3 and Rg5 obtained from Panax (ginseng) have shown significant anticancer activity via the PI3K-Akt signaling pathway. This study evaluated the anticancer and antimetastatic effects of a combination of Rg3 and Rg5 on lung cancer cells. A combination of Rg3 and Rg5 was treated for lung cancer cell line A549 and human lung tumor xenograft mouse model, and anti-metastatic effects on Matrigel plug implantation in mice. The combination of Rg3 and Rg5 showed potent antiproliferative effects on A549 cells with IC50 values of 44.6 and 36.0 μM for Rg3 and Rg5 respectively. The combination of Rg3 and Rg5 (30 µM each) showed 48% cell viability as compared to Rg3 (72% viability) and Rg5 (64% viability) at 30 µM concentrations. The combination of Rg3 and Rg5 induced apoptosis in A549 cells characterized by activation of caspase-9 and caspase-3 and cleavage of PARP, as well as suppression of the autophagic marker LC3A/B. The antitumoral potentials of the combination of Rg3 and Rg5 were ascertained in a lung tumor xenograft mouse model with high efficacy as compared to individual ginsenosides. The metastasislimiting properties of the combination of Rg3 and Rg5 were assessed in Matrigel plug implantation in mice which showed the potent efficacy of the combination as compared to individual ginsenoside. Mechanistically, the combination of Rg3 and Rg5 inhibited the expression of PI3K/Akt/mTOR and EGFR/VEGF signaling pathways in lung cancer cells. Results suggest that the combination of Rg3 and Rg5 suppressed the tumor cell proliferation in lung cancer cells and limited the rate of metastasis which further suggest that the combination has a significant effect as compared to the administration of single ginsenoside.
Keywords: antimetastatic; antitumor; apoptosis; ginsenoside; herbal medicine; lung cancer.