TMPRSS4 Promote Proliferation And Metastasis By Regulating CLDN1 In Hepatocellular Carcinoma

Objective: 1)To analyze the expression level and biological functions of TMPRSS4 and CLDN1 in hepatocellular carcinoma(HCC).2)To examine the regulatory mechanism of CLDN1 induced proliferation and metastasis in HCC.Methods: 1)RT-PCT and Western blot assays analyzed the expression patterns of TMPRSS4 and CLDN1 in HCC and adjunct normal tissues,and determined the roles of TMPRSS4 and CLDN1 in predicting prognosis.In addition,spearman analysis revealed a positive correlation between them.2)Overexpression of TMPRSS4 in HCC cells by lentivirus or knockdown of TMPRSS4 by shRNA-to identify the roles of TMPRSS4 in development of HCC and the effects to cell invasion and migration and to CSC formation.3)Overexpression of CLDN1 in HCC cells by lentivirus or knockdown of CLDN1 by shRNA-to identify the role of CLDN1 in development of HCC and the effect to cell invasion and migration and to CSC formation;4)Moreover,established a new axis consisted of TMPRSS4 and CLDN1.Results: 1)The expression levels of TMPRSS4 and CLDN1 were up-regulated in HCC tissues,compared to that of normal tissues.The expression of TMRPSS4 and CLDN1 had no significant relation with the age,sex,but were positively associated with TNM stage and differentiation degree.In addition,TMPRSS4 and CLDN1 can predict prognosis,the patients with high expression levels of TMPRSS4 and CLDN1 had a poorer overall survival than those with low expression levels ofTMPRSS4 and CLDN1.The expression level of CLDN1 was positively correlated with TMPRSS4 expression.PCR assays further confirmed that results in HCC cell lines.2)In second part,we made a special effort to study the function of TMPRSS4 on cell proliferation and migration.Previous studies demonstrated that TMPRSS4 could induce CSC phenotype formation in lung cancer and rectum cancer.In this study,function assays demonstrated that TMPRSS4 could also promote CSC formation in HCC.3)In the third part,the function roles of CLDN1 on cell proliferation and migration were discussedand and we cleared the regulatory mechanism between TMPRSS4 and CLDN1.MTT and Transwell assays demonstratedthat excessive expression of CLDN1 resulted in cell proliferation and cell invasion.While depletion of CLDN1 suppressed cancer cell growth and inhibited the migration rate of cells.Moreover,CLDN1 could induce CSC phenotype formation in HCC.In addition,we convinced that TMPRSS4 induced CSC traits though regulating CLDN1 expression via ERK pathway,an axis consisted of TMPRSS4/ERK/CLDN established.Conclusion: In this study,we found that CLDN1 was highly expressed in HCC tissues and cell lines,which indicated the crucial roles of CLDN1 in formation and progression of HCC cancer.Further,we identified a new axis that consisted of TMPRSS4/ERK/CLDN1 in cell proliferation,migration and CSC formation.In addition,we confirmed our finding though interference of CLDN1.The results suggested that CLDN1 can suppress proliferation and invasion of HCC cells,resulting in inhibition of xenograft tumor growth.These findings provide new strategy for HCC treatments.