The Effect And Mechanism Of Croton Alkaloids On The Growth And Apoptosis Of Lewis Mice Lung Adenocarcinoma Cells

Objective: In this study,We aimed to explore the effects of croton alkaloids(CA)on the growth and pathomorphology of Lewis mice lung adenocarcinoma cells,and reaearch the regulation of apoptosis-related proteins(Bax,Survivin,Caspase-3)and the potential signal transduction pathway of Hippo-YAP via in Lewis mice lung adenocarcinoma cells.To diccuss the effects of CA on growth and apoptosis of lung adenocarcinoma and its specific mechanism.We hope to find a potential new target for the treatment of lung adenocarcinoma and new drugs for the clinical treatment of lung adenocarcinoma.Methods: Lewis mouse-derived lung adenocarcinoma cells(LLC)were cultured,and subcutaneous tumorigenesis model of mice was divided in 5 groups.Group A: control group,10 mice without any treatment;group B: 10 mice of low dose group of CA,the dose of CA was 0.6mg/kg;group C: 10 mice of medium dose group of CA,the dose of CA was 1.2mg/kg;group D: 10 mice of high dose group of CA,the dose of CA was2.4mg/kg;group E: 10 mice of cisplatin group,the dose of cisplatin was 75 mg / m2.After one week,given the drug intervention to the subcutaneous neoplasia of group A,B,C,D and E.On the 22 nd day,Lewis mice in five groups were weighed to measure the tumor growth rate.To research the effect of CA on LLC by calculating the tumor volume,tumor weight,tumor inhibition rate and observing the changes of Pathomorphology in each group.Western blots and RT-PCR were used to detect the expression of apoptosis related proteins and genes Yap,Bax,Caspase-3,Survivin,to explore the mechanism of CA in promoting the apoptosis of lung adenocarcinoma cells.Results: 1.The effect of CA on the general survival state of Lewis lung adenocarcinoma mice: the general survival state of group C and group D mice was better than that of group A,B,E,but the difference of activity sensitivity and appetite decline were not obvious.2.HE staining of tumor tissues in each group: the results showed that the tumor cells in groups B,C,D and E showed different degrees of apoptosis,while the tumor cells in group A were mostly necrotic cells.3.CA has a certain inhibitory effect on the growth of mouse tumor-forming tumor induced by mouse lung cancer LLC cells: weigh the tumor weight,calculate the tumor volume and tumor inhibition rate after taking out thetumor.The tumor inhibition rates of group B,C,D and E are 13.91%,14.83%,27.84%and 68.45%.The results of the statistical analysis showed that compared with group B and group C,the group D had statistical significance,and compared with group D,the group E had statistical significance(P<0.05).4.The expression of Yap,Bax,Caspase-3 and Survivin gene was detected by RT-PCR in each group(A group and B,C,D different doses of CA Group).It was found that the expression of Survivin in different doses of CA Group was lower than that in control group(group A).The higher the dose of CA,the lower the expression of Survivin;The higher the CA dose,the higher the expression of Bax and Caspase-3 proteins.YAP did not change significantly in each group and has not statistically significant.5.Western blot was used to detect the effect of the control group(group A)and the groups with different doses of CA(group B,C,D)on the expression of apoptosis-related proteins.However,Bax and Caspase-3 were both higher than the control group at different doses of CA(group A).The higher the CA dose,the higher the expression of Bax and Caspase-3 proteins.YAP did not change significantly in each group and was not statistically significant.Conclusions: 1.CA can inhibit the growth of Lewis lung adenocarcinoma mice tumors and cause the apoptosis of cells.2.CA can induce the apoptosis of Lewis lung adenocarcinoma mice tumor cells by up-regulating the expression of protein and gene protein and gene expression,and the down-regulating the expression of survivin.3.The regulatory mechanism may be through down-regulation of Survivin expression,so that Survivin's inhibitory effect on Caspase-3 protein is weakened,and Bax up-regulation can further activate Caspase-3 protein,thereby inducing Caspase cascade effect to promote cell apoptosis,which provides new targets for lung adenocarcinoma treatment.