Roles Of NOK In NSCLC Proliferation And Metastasis:A Clinical And Experimental Study

Background: Both morbidity and mortality of lung cancer rank the first of all the malignant tumors in the world wide.In 2012,106 patients were diagnosed with lung cancer in every 100 thousand people,and this number is increasing.Because of the higher incidence,higher mortality and higher invasion ability of lung cancer,less than 15% patients survive more than 5 years.Lung cancer can be divided into adenocarcinoma(40%),squamous carcinoma(30%),large cell lung cancer(15%)and small cell lung cancer(15%).Lung cancer is hard to be diagnosed in the early stage.Therefore,the inner mechanism of lung cancer has been studying in the last decades.Novel oncogenic kinase(NOK),also known as a putative serine/threonine and tyrosine receptor protein kinase(STYK)1,belongs to receptor protein tyrosine kinase(RPTK)family.RPTKs play important roles in cell proliferation,cell transformation and cell differentiation.Dysfunction of RPTKs is believed to be an important cause of tumorigenesis.NOK expression is high in acute leukemia,lung cancer,ovarian cancer and many other kind of malignant tumors.Animal experiments showed that NOK can promote xenografts growth in nude mice.Our team have proved that NOK expression in lung cancer is correlated with the TNM stage and the survival time.But the role of NOK in pleural carcinomatosis and malignant hydrothorax is not clear,neither the inner mechanisms.Protein kinase B(Akt)is widely existed in tissue and organs.Activated Akt can regulate many downstream signaling molecules,including Glycogen synthase kinase 3(GSK3),forkhead transcription factors(FOXO)and BAD.Akt inhibitor is a potential therapy of lung cancer.Jing Li proved that NOK interacts with Akt and exerts biological effect.However,whether Akt mediates the tumor promotion effect of NOK needs is not clear,and this issue will be illuminate in this study.Objective: 1.Investigate the relationship between NOK expression in pleural carcinomatosis and NSCLC TNM stage and survive time 2.Investigate the relationship between NOK expression in malignancy hydrothorax and NSCLC TNM stage and survive time 3.Investigate the role of NOK in NSCLC cells and whether Akt play a role in this process.Methods: 1.67 NSCLC patients were collected in our department.Pleural carcinomatosis and normal pleural tissue were taken and NOK m RNA and protein were detected.Meanwhile,information for patients including gender,age,TNM stage and survive time were collected.Further,the relationship between NOK expression in Pleural carcinomatosis and these clinical features were analyzed.2.140 patients were collected in our department.Malignancy hydrothorax were taken and the NOK protein as well as m RNAs were detected.Meanwhile,information of patients including gender,age,TNM stage and survive time were collected.Furthermore,the relationship between NOK expression in hydrothorax and these clinical features were analyzed 3.SPC-A1 cells were used in this part.NOK over-expressed SPC-A1 cell line were established and NOK si RNA were synthesized.Then the cell proliferation,migration and adhesion ability as well as Akt phosphorylation level were detected.Furthermore,Akt inhibitor MK-2206 was used to inhibit Akt phosphorylation,to confirm that Akt mediates the effects of NOK.Results: 1.The survival time of patients with lower NOK expression is longer than patients with high NOK expression(P<0.05).NOK expression is correlated with the TNM stage.NOK expression in normal pleura tissue has no influence in survival time.2.NOK expression in malignancy hydrothorax is correlated with the TNM stage.The survival time of patients with lower NOK expression is longer than patients with high NOK expression.3.NOK over expression significantly increased cell proliferation,migration and adhesion,with higher Akt proliferation levels.Inhibition of Akt reversed the effects of NOK overexpression,indicating that Akt might be a key mediator of NOK.Conclusion: 1.NOK expression in pleural carcinomatosis is correlated with the survival time.2.NOK expression in malignant pleural effusion is correlated with the TNM stage and patient survival time.3.NOK overexpression in SPC-A1 cell increased the cell proliferation,migration and adhesion,these effects might be mediated by Akt activation.