The Anti-Esophageal Cancer Effects And Mechanisms Of Ginsenoside Rk3

Ginsenosides are the main active ingredients of ginseng,panax notoginseng and panax quinquefolium.In recent years,ginsenosides have been widely studied due to its effective antitumor activity and low toxic side effects.Ginsenoside Rk3,a rare ginsenoside with good water solubility,has been shown to have significant anti-tumor activity against the non-small cell lung cancer.However,the antitumor effect of ginsenoside Rk3 on esophageal cancer has rarely been reported.This study aims to explore the effect of ginsenoside Rk3 on esophageal cancer cell proliferation and its potential mechanism through a series of in vitro and in vivo experiments.The main researches are as follows:1.With the conversion product of 70% Re as the raw material,the mixture of ginsenosides in triol group were separated by macroporous adsorption resin,and then the monomer of Rk3 was prepared by the preparation liquid chromatograph.After concentrated and dried,the purity of saponins was detected.The results showed that the mixture content of ginsenosides in the triol group was the highest when 60% ethanol was used as eluent,and the purity of the final ginsenoside Rk3 monomer was 97.788%.2.Ginsenoside Rk3 was used for experiments to study the effects of Rk3 on the proliferation and colony formation of esophageal cancer cells Eca109 and KYSE150,as well as normal esophageal epithelial cells HET-1A.In addition,the anti-tumor effect of Rk3 in vivo was investigated by establishing a tumor-bearing nude mouse model of KYSE150 cells.After intraperitoneal injection,the changes of body weight and tumor volume in tumor-bearing nude mice were detected,and the pathological changes of tumor,heart,liver,spleen,lung and kidney were analyzed.The results showed that Rk3 could significantly inhibit the proliferation of esophageal cancer cells and reduce the ability of cell colony formation in vitro,but had no significant effect on the HET-1A cells.At the same time,it was found that Rk3 could significantly inhibit the growth of esophageal cancer in vivo and has low toxic side effects.3.Then,we study the effects of ginsenoside Rk3 on the periodic distribution,apoptosis and autophagy of Eca109 and KYSE150 cells.According to cell cycle distribution analysis,Hoechst 33342 staining,transmission electron microscopy,AV/PI staining,western blot and immunohistochemical analysis,Rk3 blocked Eca109 and KYSE150 cell cycle in G1 phase,and could cause apoptosis and autophagy.In addition,autophagy inhibitor 3-MA could inhibit both autophagy and apoptosis induced by Rk3,indicating that autophagy induced by Rk3 can promote apoptosis.4.Finally,we investigate the effect of ginsenoside Rk3 on the PI3K-Akt-m TOR signaling pathway.Western blot and immunohistochemical analysis showed that Rk3 can negatively regulate the pi3k-akt-mtor signaling pathway.In addition,both Akt and m TOR inhibitors can enhance the apoptosis and autophagy induced by ginsenoside Rk3.The above studies indicated that ginsenoside Rk3 regulates apoptosis and autophagy of esophageal cancer cells through PI3K-Akt-m TOR signaling pathway.This study is the first to clarify the mechanism of Rk3’s anti-esophageal cancer effect,laying a theoretical foundation for the development and application of Rk3.