Study On The Anti-Tumor Effects Of Dendrobium Huoshanense On Lewis Lung Cancer In Vitro And In Vivo

Background: Cancer has become the second most common disease that affects and threatens human health because of environmental pollution,nutritional imbalances and increased stress on life.The morbidity and mortality of lung cancer is the highest one in malignant tumors,and the incidence of lung cancer appears an increasing trend.Currently,the use of traditional Chinese medicine and some natural small molecule substances to treat cancer has been increasingly favored by the medical community.It is one of the ways to develop new anticancer drugs to find antitumor active sites and effective monomeric compounds from traditional Chinese medicines.Dendrobium huoshanense is a precious Chinese herbal medicine recorded in ancient Chinese Materia Medica and has a long history of edible and medicinal purposes.Therefore,it is of great significance to explore the potential anti-tumor activities of the main medicinal components of Dendrobium huoshanense.Objective: In this paper,we studied the anti-tumor effects of the extracts from Dendrobium huoshanense stems on Lewis lung cancer in vitro and in vivo,to determine the effective antitumor components,investigate the anti-tumor mechanism of Dendrobium huoshanense,and find a new efficient and low toxicity anti-tumor drug in the clinical treatment of lung cancer.Methods: 1.To study the effect of different extraction components of Dendrobium huoshanense on LLC cells in vitro:(1)MTT assay was used to detect the inhibition of D.huoshanense on the proliferation of LLC cells;(2)Flow cytometry was used to detect the effects of different fractions of D.huoshanense on the apoptosis and cell cycle of LLC cells.2.To study the anti-tumor effect of different extraction components of Dendrobium huoshanense on LLC tumor-bearing mice in vivo:(1)C57BL/6J mice xenograft model of Lewis lung cancer was established.(2)The survival ability of each group of mice was observed and the physiological indexes of mice were recorded.(3)The secretion of tumor related cytokines in serum of LLC tumor bearing-mice was detected by ELISA method.(4)Mice splenic lymphocyte proliferation test and flow cytometry were used to detect the immune cells changes.Results: 1.The dried powder of Dendrobium huoshanense stems were successively extracted by ethanol extraction,water extraction,and ethanol precipitation to obtain ethanol extracts,water extracts and refined polysaccharides(c DHP)with extraction rates of 20.44 %?35.31 %?18.45 %.2.The anti-tumor experiments in vitro showed that D.huoshanense could inhibit the growth of LLC cells;48 h after administration,the inhibitory effect of c DHP group is obvious in a dose-dependent manner;The amounts of apoptotic cells in c DHP group increased,the cell cycle was blocked,and the proliferation was inhibited.3.The experiments in vivo showed that the extracts of D.huoshanense all inhibited tumor growth in LLC tumor-bearing mice,of which c DHP group have the best inhibition rate,which were significantly different from the model group(p<0.05);the results of organ indexes showed that immune organ functions of tumor-bearing mice were improved to a certain extent,which had efficacious protection and recovery effect on immune system in vivo;The results of immune cytokines secretion by ELISA method and immune cell changes by flow cytometry in tumor-bearing mice showed that D.huoshanense can enhance the immune function.In summary,we screened out a refined polysaccharide of D.huoshanense(c DHP)which has obvious anti-tumor efficacy,explored its anti-tumor effect through a series of immune regulation and provided a theoretical basis for clinical application.