The Role And Mechanism Of TNKS1 In Regulating The Development Of Ovarian Carcinoma Through Wnt/?-catenin Signaling Pathway

BackgroundOvarian cancer is one of the three major malignant tumors in the gynecological reproductive system.Due to the absence of early warning symptoms and lack of sensitive early detection markers,the majority of cases are diagnosed at an advanced stage with a high incidence of recurrence and metastasis.Current treatment has been limited by resistance to chemotherapy and insensitive to radiotherapy which results in poor prognosis.Therefore,it's urgent to better understand the mechanisms underlying the development of ovarian cancer,which is important to the identification of effective early diagnosis markers and prognostic indicators as well as the development of gene-targeted therapy.Tankyrase(TNKS)belongs to the poly ADP ribose polymerase(PARP)protein family.It is the first protein that can bind to the repeat binding sequence of telomerase.The human TNKS1 gene residues on chromosome 8(p23.1).As a key regulator of telomere length,TNKS 1 plays a key role in various diseases including many malignant tumors.However,the role of TNKS 1 in ovarian cancer remains unclear.The Wnt/?-catenin signaling pathway plays an important role in the development and progression of malignant tumors.Studies have confirmed that TNKS positively regulates the Wnt signaling pathway.This study is the first to investigate the underlying mechanisms of TNKS1 in the development of ovarian cancer by regulating the Wnt/?-catenin signaling pathway.ObjectivesThis study systematically and stereoscopically investigated the role and mechanism of TNKS 1 in the development of ovarian cancer from the clinical samples,cell level,animal model and molecular mechanism level,in order to provide scientific data for clinical diagnosis and therapy of ovarian cancer.Materials and methods1.The expression of TNKS 1 was assessed by real-time quantitative PCR,immunohistochemistry,and western blot analysis with clinical ovarian cancer tissue samples.2.The effect of TNKS 1 on the proliferation and tumorigenesis of ovarian cancer cells was assessed by the MTS method,colony formation,and Tumor Xenografts.3.The effect of TNKS 1 on the drug sensitivity of ovarian cancer cells was measured by MTS and apoptosis.4.The role of TNKS 1 in migration and invasion of ovarian cancer was studied by wound-healing and transwell assays.5.The role of TNKS 1 in aerobic glycolysis of ovarian cancer cells was assessed by glucose uptake,lactate excretion,ATP levels,and O2 consumption rates mitochondrial oxygen consumption rate.6.The molecular mechanism of TNKS1 involved in the development of ovarian cancer was measured by western blot analysis and cell transfection.7.Statistical analysis was performed by SPSS21.0 statistical software.Statistical significance was determined as P<0.05Results1.The expression of TNKS1 in ovarian cancer tissues was significantly higher than that in paracancerous tissues and normal ovarian tissues,which was closely associated with pathological differentiation and tumor size.2.Knockdown or inhibition of TNKS1 not only significantly inhibited ovarian cancer cell proliferation,cell colony formation,in vivo tumorigenesis and cell cycle progression,but also effectively improved the sensitivity of ovarian cancer cells to commonly used chemotherapy drugs and inhibited their migration and invasion ability.In addition,TNKS1 knockdown or inhibition suppressed the aerobic glycolysis of ovarian cancer cells and enhanced the mitochondrial oxygen consumption rate by reducing Pyruvate carboxylase expression.3.Knockdown or inhibition of TNKS1 resulted in inactivating Wnt/?-catenin signaling and then downregulated the expression of its downstream proteins including Snail,PC,Cyclin D,MDR,and MMP-9.The expression of TNKS1 is positively correlated with snail and PC in clinical ovarian cancer samples.ConclusionsTNKS1 is highly expressed in ovarian cancer tissues,indicating an important role in ovarian cancer.TNKS1 may promote the proliferation,tumorigenesis,migration,and invasion of ovarian cancer and reduce the drug sensitivity by activating Wnt/?-catenin signaling pathway.TNKS1 may also promote the aerobic glycolysis of ovarian cancer cells through ?-catenin/Snail/PC signaling pathway.TNKS1 plays an important role in the development of ovarian cancer,which might be used as a potential diagnostic marker,prognostic indicator,or therapeutic target of ovarian cancer.