The Expression Of PRMT2in Thyriod Cancer And Its Mechanisms Controlling CCND1Expression In TPC-1Cells

Objective: To test the expression level of PRMT2in thyroid cancer and normaltissue,investigate the impact of exogenous of PRMT2on the expressing of CCND1and PI3K in human thyroid cancer cell line TPC-1；and to test the molecularmechanism of PRMT2regulating the expression of CCND1.Methods:Tissue microarray was carried out to analyze the correlation betweenPRMT2expression and clinical parameters in thyroid cancer.Human thyroid cancercell line, TPC-1cells were transfected with expression plasmidpcDNA3.2/V5-PRMT2(different concentration), and pc DNA3.2/V5(empty plasmidas control) by using Lipofectamine2000.Western blot were applied,to test the impactof exogenous of PRMT2on the expressing of CCND1and PI3K in TPC-1cells；Andthen, pretreated cells with Akt inhibitors(LY294002or Wortmannin)respectively,western blot to test the impact of exogenous of PRMT2on the expressingof CCND1and PI3K in human thyroid cance cell line TPC-1after pretreated byinhibitors.Results:1)Tissue microarray immunohistochemistry results showed that PRMT2expression in thyroid cancer tissues was significantly higher than that in normalthyroid tissue (P <0.05). PRMT2nuclear expression in normal thyroid tissue wassignificantly higher than that in thyroid cancer tissues(P <0.05).PRMT2expressionwas found to be related with age,PRMT2expression in patients aged older than50with thyroid cancer was significantly higher than that in younger patients with thyroidcancer(P<0.05); No correlationship was observed between PRMT2expression andtumor size lymph node metastasis、pathological type.(P<0.05).2)CCND1and PI3K protein levels significantly decreased in TPC-1cells thatwere stable transfected with over-expressing exogenous PRMT2by Western blot.3)Western blot results showed that the protein levels of CCND1and PI3Ksignificantly decreased in TPC-1cells which were pretreated with Akt inhibitors(LY294002or Wortmannin).Conlusion:1)Compared with normal thyroid tissue, PRMT2shows a higher expressionin thyroid carcinoma,the level of PRMT2in cell nucleus of thyroid cancer tissueshowed obvious decrease compared with those in normal thyroid tissue and theexpression of PRMT2in thyroid carcinoma is shown to be associated with age.2) PRMT2downregulates CCND1expression via the suppression ofAkt/GSK-3βsignaling in TPC-1cells.