USP39 Promotes The Proliferation Of Lung Cancer Cells By Regulating FoxO1 Expression

Background Lung cancer is one of the most common malignant tumors in human beings,and the main cause of cancer death as well.Compared with most tumors whose survival rates increase steadily,the treatment of lung cancer is still a big problem,and its pathogenesis is still to be uncovered.Among a variety of target molecules of lung cancer,ubiquitin-specific protease 39(USP39)is involved in the regulation of cell migration,senescence,apoptosis and other processes of many cancer cells,but its role and molecular mechanism in lung cancer remains unclear.Objective To investigate the expression of USP39 in NSCLC,to screen and validate the function and its downstream signaling molecules;To explore the role of USP39 and its downstream target FoxO1 in the occurrence and progression of NSCLC.Methods The immunohistochemistry,endogenous immunofluorescence and Western blot were used to explore the expression of USP39 in lung cancer tissues,the subcellular localization in lung adenocarcinoma cells.By using lentiviral shRNA packaging and infection or transient siRNA transfection knockdown experiments of USP39 and FoxO1 in lung cancer cells including A549 and H1975.The effects of USP39 and its downstream target FoxO1 on the cell growth,proliferation of lung adenocarcinoma cell lines.Results In A549 cells,USP39 was mainly localized to the nucleus,while FoxO1 mainly to the cytoplasm.USP39 knockdown inhibits the proliferation of lung cancer cell line A549,and can downregulates the FoxO1 expression.FoxO1 knockdown can also affect the proliferation of A549.Conclusion USP39 may promote the occurrence of lung cancer by regulating the expression of FoxO1 in lung adenocarcinoma cells.