Inhibitory Effect Of Poria Polysaccharide Combined With Cisplatin On Transplanted Lewis Lung Adenocarcinoma And The Expression Of VEGF、p-STAT3 And CD31

Objective Through the establishment of a nude mouse xenograft model of Lewis lung adenocarcinoma,the effects of Poria polysaccharide combined with cisplatin on the growth of Lewis lung adenocarcinoma and the expression of CD31,p-STAT3,and VEGF were explored,and the anti-tumor mechanism of Poria polysaccharide was further studied.Methods The Lewis lung adenocarcinoma cells were inoculated into the right anterior armpit of nude mice to establish a nude mouse xenograft model of lung adenocarcinoma.36 nude mice were randomly divided into model group(Model),cisplatin group(DDP),tuckahoe polysaccharide group(PCP),tuckahoe polysaccharide combined with cisplatin group(PCP+DDP),9 mice in each group.The model group was given intraperitoneal injection of 0.2 m L of 0.9% sodium chloride,once every other day,and intragastrically 2 m L of normal saline,once a day.The cisplatin group was given intraperitoneal injection of 2mg·kg-1 cisplatin0.2m L,once every other day.The tuckahoe polysaccharide group was given 40 mg·m L-1 tuckahoe polysaccharide 2ml by gavage,once a day.The tuckahoe polysaccharide combined with cisplatin group was given intraperitoneal injection of 2mg·kg-1 cisplatin 0.2m L,once every other day,and gavage 40mg·m L-1 tuckahoe polysaccharide 2ml once a day.Observe the tumor volume changes of nude mice during the medication,and draw the tumor growth curve.The administration was continued for28 days,and the nude mice were sacrificed by de-neck method after stopping the drug for 1 week.The tumors were stripped and weighed,and the tumor growth inhibition rate was calculated.Immunohistochemical staining of CD31 was used to evaluate microvessel density(MVD)counts,and real-time quantitative PCR and Western blot detection(Western Blots)were used to detect lung cancer tissue transcription factor activator 3-p(p-STAT3)and vascular endothelial growth factor(VEGF)m RNA and protein expression.Results Compared with the model group,the PCP group,the PCP group,the PCP combined with DDP group can significantly inhibit the growth of tumor volume in nude mice(P<0.05),and the administration of the PCP combined with DDP group inhibits tumor The rate(84.43%)was significantly higher than that of the DDP group(58.35%)and the PCP group(26.30%).Immunohistochemistry showed that the area of blood vessel density in the PCP combined with DDP group was significantly reduced compared with the other three groups.In addition,the relative expression levels of VEGF and p-STAT3 in the tumor tissues of the PCP group,DDP group,PCP combined with DDP group were lower than the model group,and the PCP combined with DDP group was the lowest,and the difference was statistically significant(P<0.05).Pearson correlation analysis showed that there was a positive correlation between p-STAT3 and VEGF expression(r=0.955,P<0.0001),suggesting that p-STAT3 is related to tumor angiogenesis.Conclusion Poria cocos polysaccharide can inhibit the growth of lung cancer transplanted tumors,and its combination with cisplatin can play a synergistic effect.The anti-tumor mechanism of Poria cocos may be to down-regulate the expression of VEGF by inhibiting the expression of p-STAT3,thereby exerting an anti-tumor angiogenesis effect.