Ginseng and its components exert various biological effects, including antioxidant, anti-carcinogenic, anti-mutagenic, and antitumor activity. Ginsenosides are the main biological components of ginseng. Protopanaxadiol (PPD) and protopanaxatriol (PPT) are two metabolites of ginsenosides. However, the difference between these compounds in anti-lung cancer is unclear. The present study aimed to evaluate the antitumor activity of PPD, PPT, Ginsenosides-Rg3 (G-Rg3) and Ginsenosides-Rh2 (G-Rh2) in lung cancer cell. After treatment with cisplatin, PPD, PPT, G-Rg3 or G-Rh2, the viability, apoptosis level and invasiveness of lung cell lines (A549 cell, a lung adenocarcinoma cell line and SK-MES-1 cell, a lung squamous cell line) in vitro were analyzed by Cell Counting Kit-8 (CCK8), Annexin V/PI apoptosis and Matrigel invasion assays, respectively. Here we found that all these compounds led to significant decreases of viability and invasiveness and an obvious increase of apoptosis of A549 and SK-MES-1 cells. Among these, the viability of SK-MES-1 cell treated with PPT was decreased to 66.8%, and this effect was closest to Cisplatin. G-Rg3 had the highest stimulatory effect on apoptosis, and PTT had the highest inhibitory effect on cell invasiveness in A549 and SK-MES-1 cells. These results indicate that both ginsenosides and two metabolites have antitumor activity on lung cancer cell in vitro. However, PPT is more powerful for inhibiting the viability and invasiveness of lung cancer cell, especially lung squamous cell. G-Rg3 has the best pro-apoptosis effects. This study provides a scientific basis for potential therapeutic strategies targeted to lung cancer by further structure modification.
Keywords: Ginsenosides; PPD; PPT; antitumor activity; lung cancer cell.