The Role And Molecular Mechanism Of CXCL16/CXCR6 Axis In Promoting The Development Of Lung Adenocarcinoma

Background:Lung cancer is a serious threat to human health,it has high incidence and mortality rate in China^[1].Non small cell lung cancer is the most common type of lung cancer,about 85%of lung cancer is non-small cell lung cancer^[2].The incidence of lung adenocarcinoma is about80%in non-small cell lung cancer^[3].The latest research shows that the 5 year survival rate of patients with non-small cell lung cancer is less than 15%,while the 10 year survival rate is less than 7%^[4].Because more than half of non-small cell lung cancer patients are diagnosed with distant metastasis^[5].The development and metastasis of lung cancer are the main causes of poor prognosis in patients.However,the mechanism of the development and metastasis of lung cancer has not been fully elucidated,and the mechanism of lung cancer metastasis,especially the mechanism of early metastasis,has become a severe and urgent task in the prevention and treatment of lung cancer.It is of great significance to improve the treatment strategy of lung cancer patients,improve the prognosis and improve the survival rate.CXCL16 is a chemokine that is secretied intercellular space,CXCR6 is its receptor and exists on the cell surface.The interaction between CXCL16 and CXCR6 is related to many biological effects such as cell migration,immunity and so on.CXCR16/CXCR6 axis is closely related to the progression and metastasis of many tumors,Include thyroid cancer,prostate cancer,bladder cancer,and gastric cancer.Activation of CXCL16/CXCR6 enhance tumor cell growth,adhesion and directional migration^[6].CXCL16/CXCR6 also plays an important role in the development and metastasis of lung cancer,which directly affects the proliferation,migration and invasion of lung cancer cells^[6,9].However,how the CXCL16/CXCR16 axis affects the biological status of lung cancer cells,the mechanism is still unclear.JAK2/STAT3 molecular pathway is a signal transduction pathway stimulated by cells and molecules involved in cell proliferation,differentiation,apoptosis and immune regulation and many other important biological processes.JAK2 and STAT3 are activated in many tumors^[7,8,9].t has been reported that RANKL can inactivate JAK2/STAT3 signaling pathway by reducing the production of CXCL16 during osteoclastogenesis^[10].JAK2/STAT3 pathway can regulate cell adhesion and migration by regulating the AKT/mTOR pathway.CXC16/CXCR6 axis may mediate JAK2/STAT3 phosphorylation to obtain a complete molecular pathway to achieve the development and metastasis of lung adenocarcinoma,and enhance the ability of lung adenocarcinoma cells to proliferate,invade and metastasize is increased.But the pathway of its functional stage is still unclear.This topic will revolve around this scientific hypothesis.ambition:The lung adenocarcinoma cells with high and low expression of CXCL16 were constructed by lentivirus transfection to observe the effect of CXCL16/CXCR6 axis on lung adenocarcinoma cells.method:1.Lewis lung adenocarcinoma metastasis mouse model was constructed.The expression levels of CXCL16 and CXCR6 in lweis lung adenocarcinoma cells at metastatic sites in vivo were examined by histological section.2.Lentivirus transfection technique was used to construct mock?untreated A549 cells?,NC?Lentivirus A549 cells of CXCL16 knocked down?,A3?A549 cells of CXCL16 knocked down?,CTR?A549 cells of CXCL16 knocked up?,L16?A549 cells of CXCL16overexpressed?.3.The proliferation,migration and invasiveness of the cell lines were measured by ED^M labeling,CCk-8 reagent,monoclonal test,scratch test and Transwell chamber test.4.Real-time quantitative PCR?qRT-PCR?and Western blot were used to detect the mRNA and protein expression of CA916798 gene in cancer tissues.5.The possible downstream molecular pathways of CXCL16/CXCR6 were selected from the above data and further validated by Transwell chamber experiment.result:1.The tumor bearing test in mice showed that CXCL16 and CXCR6 were expressed in tumor bearing tissues of lung adenocarcinoma.2.EDU labeling,CCK-8,and monoclonal assay showed that the proliferation ability of the above cell lines was PRO>>mock CTR ShNC>ShRNA,respectively.3.Scratch test and Transwell chamber migration test showed that the migration ability of the above cell lines were PRO group>>mock CTR ShNC>ShRNA,respectively.4.The Transwell invasion test showed that the invasive ability of the above cell lines was PRO>>mock CTR ShNC>ShRNA,respectively.5.The expression of CXCL16 in PRO group>mock CTR ShNC>ShRNA was confirmed by qrt-PCR and Western blot.CXCR6 increased with the increase of CXCL16expression.And CXCL16 can promote the expression of CXCL16.CXCXL16/CXCR6 its downstream molecular pathway is Jak2/STAT3.And activation of Jak2/STAT3 can promote the occurrence of EMT in lung adenocarcinoma cells.6.Transwell chamber experiments with STAT3 agonists and inhibitors further demonstrated that the downstream molecular pathway of CXCL16/CXCR6 was JAK2/STAT3.conclusion:In vivo experiments showed that CXCL16 and CXCR6 were expressed in lung adenocarcinoma...