The Effects Of PRMT2 On Akt/CCND1 Signaling Pathway Through TRβ In Thyroid Carcinoma TPC-1 Cells

Objective: To preliminary study the fuctions and mechanisms of protein arginine methyltransferase 2(PRMT2) and thyroid hormone receptor β(TRβ) in thyroid carcinoma TPC-1 cells.Methods: 1. The human thyroid carcinoma TPC-1 cell stably expressing PRMT2 were devided into two groups: tetracycline induced group(+dox group,cells expressed high level PRMT2 were induced by tetracycline) and negative control group(-dox group, cell cultures were no tetracycline added)to preliminary study the protein interaction between PRMT2 and TRβ.2. siRNA interference technique was used to achieve the silence of TRβ. Under the condition,we established tetracycline induced group, TRβ/sh RNA group, tetracycline induced group &TRβ/sh RNA group,and negative control group to further study the influences of PRMT2 and TRβ on cell proliferation of thyroid cancer TPC-1 cell. Western Blot analysis was used to assay the protein level of CCND1 and p-Akt which are closely correlated to the proliferation of cancer cell;dual luciferase reporter gene system was used to detect the influence of PRMT2 and TRβ on the activity of CCND1 promoter to further evaluate the effect on cell proliferation.Results:1. The expression of TRβ was downregulated by over-expression of PRMT2(P<0.05),but knockdown of TRβ had no significant effect on the protein level of PRMT2.2.Western Blot showed that the protein level of p-Akt and CCND1 were decreased by knockdown of TRβ or over-expression of PRMT2(P<0.05),and on the basis of over-expression of PRMT2,knockdown of TRβ could lead to the proteins level of p-Akt and CCND1 further declined(P<0.05).3. Silencing of TRβ or over-expression of PRMT2 can both decrease the activity of CCND1 promoter; on the basis of over-expression of PRMT2, knockdown of TRβ can further decrease the activity of CCND1 promoter(P<0.05).Conclusions: PRMT2 could inhibit the Akt/ CCND1 signal pathway through TRβ in thyroid carcinoma TPC-1 cells.