Ginsenoside Rg3 Sensitizes Nasopharyngeal Carcinoma Cells to Radiation by Suppressing Epithelial Mesenchymal Transition.

Radioresistance restrains the therapeutic effect of nasopharyngeal carcinoma (NPC). Ginsenoside Rg3 (Rg3), an active pharmaceutical component extracted from ginseng, shows antitumor effects in various cancers. In this study, we aimed to determine whether Rg3 sensitized NPC cells to radiation and to explore the possible mechanisms. Our results revealed that Rg3 increased radiosensitivity in both HNE1 and CNE2 cell lines. Radiation-induced epithelial mesenchymal transition (EMT) in NPC cells and Rg3 blocked this effect. In addition, Rg3 attenuated radiation-induced epidermal growth factor receptor (EGFR) nuclear transport and DNA-dependent protein kinase expression. What's more, Rg3 significantly accelerated the apoptosis rates in irradiated NPC cells. In summary, our data suggested that Rg3 sensitized NPC cells to radiation and suppressed radiation-induced EMT. This effect is mediated through restrained EGFR nuclear translocation and increased cell apoptosis. Thus, Rg3 may be a potential radiation sensitizing agent for NPC.