Ginsenoside Rp1-induced apolipoprotein A-1 expression in the LoVo human colon cancer cell line – Accepted Manuscript

Abstract: Background: Ginsenoside Rp1 (G-Rp1) is a novel ginsenoside derived from ginsenoside Rk1. This compound was reported to have anti-cancer, anti-platelet, and anti-inflammatory activities. In this study, we examined the molecular target of G-Rp1’s anti-proliferative and pro-apoptotic activities.Methods: To examine the effects of G-Rp1, cell proliferation assays, propidium iodine staining, proteomic analysis by two-dimensional gel electrophoresis, immunoblotting analysis, and a knockdown strategy were employed.Results: G-Rp1 dose-dependently suppressed the proliferation of colorectal cancer LoVo cells and also increased the apoptosis of these cells. Interestingly, G-Rp1 remarkably up-regulated the protein level of apolipoprotein (Apo)-A1 in LoVo, SNU-407, DLD-1, SNU-638, AGS, KPL-4, and SK-BR-3 cells. The knockdown of Apo-A1 by its siRNA increased the levels of cleaved poly(ADP-ribose) polymerase (c-PARP) and p53 and diminished the proliferation of LoVo cells.Conclusion: These results suggest that G-Rp1 may act as an anti-cancer agent by strongly inhibiting cell proliferation and enhancing cell apoptosis through the up-regulation of Apo-A1.