The Role Of YY1 And MiR-186 And Their Interaction Network In Non-small Cell Lung Cancer

Lung cancer is the leading cause of cancer-related death worldwide.Despite the improvement in surgery and chemotherapy,the prognosis of patients with advanced lung cancer is still poor.In recent years,development of molecular biology research in lung cancer have helped to find new treatment of lung cancer and drug development.The study of the occurrence and development of lung cancer at the molecular biology level will help us to discover new biomarkers for lung cancer treatment.We studied the role of transcription factors Yin Yang-1(YY1),microRNA miR-186,IncRNA PVT1 and their interaction network in lung cancer.Yin Yang-1(YY1)is a multifunctional transcription factor that exhibits positive and negative control on a large number of cellular and viral genes.A large number of studies have demonstrated that PVT1 is abnormally expressed in many types of human cancer.miR-186 was found decreased in various human malignancies and function as a tumor suppressor.However,the regulating mechanism of miR-186 in growth and metastasis of human non-small cell lung cancer is still poorly understood.In this study,we collected lung cancer patients with cancerous tissues and adjacent tissues,the human lung cancer cell lines A549,95-D,HCC827,NCI-H1650 and pulmonary epithelial HPAEpiC cell lines.Firstly,we used qRT-PCR or western blot to detect the expression of these gene/RNAs in lung cancer tissues/adjacent tissues and lung cancer cell lines.The cell proliferation was detected by CCK-8 assay.Cell apoptosis was detected by flow cytometry.Transwell was used to detect cell migration and invasion.The mutual targeting between these gene/RNAs was verified by luciferase reporter assay,electrophoretic migration assay and chromatin immunoprecipitation assay.Results showed that the expression of YY1 in lung cancer tissues and lung cancer cell lines was significantly up-regulated.The overexpression of YY1 promoted the proliferation,migration and invasion of cancer cells and inhibited the apoptosis.YY1 can bind directly to the IncRNA-PVT1 promoter and activate its transcription.PVT1 can also promote cell proliferation,migration and invasion of lung cancer cells.MiR-186 is down-regulated in lung cancer tissues and cells.Overexpression of miR-186 inhibits the proliferation,migration and invasion of lung cancer cells and induces apoptosis.MAP3K2 is highly expressed in lung cancer tissues,and MAP3K2 can promote the proliferation,migration and invasion of lung cancer cells and inhibit apoptosis.MiR-186 can target MAP3K2 and inhibit the expression of MAP3K2.In addition,MAP3K2 overexpression reverses the inhibitory effect of miR-186 on proliferation and metabolism of lung cancer cell lines to a certain extent.MiR-186 was negatively correlated with YY1 expression in lung cancer and lung cancer cell lines.MiR-186 was directly targeted to YY1.The effect of YY1 siRNA on cell proliferation,cell invasion and cell migration,and induction of apoptosis was significantly stronger than that of miR-186.In summary,our study shows that YY1 could play a role in promoting tumor in the process of by affecting its downstream target PVT1.MiR-186 can regulate the growth and metabolism of lung cancer by inhibiting the expression of MAP3K2,and induce the apoptosis of non-small cell lung cancer cells by direct targeting of YY1.Therefore,miR-186-MAP3K2 and miR-186-YY1 might be a new,useful,potential clinical treatment and diagnostic target for non-small cell lung cancer treatment.