Research On Mechanisms Of Proliferation Inhibited By THRB Gene In Breast Cancer Cells

Objective: Thyroid hormone receptorβ1 is associated with human tumorigensis and development,however its role and the mechanism in breast cancer is inclusive.In this study,we overexpress thyroid hormone receptor β1 gene in breast cancer cell lines by lipofectamine transfection to explore its effect on proliferation of breast cancer cell and the mechanisms triggering this event.Methods: MDA-MB-231 and MCF-7 cell lines are picked up to perform lipofectamine transfection to overexpress THRB gene in the two lines.Efficiency of transfection is verified by result of western blotting.Proliferation index of breast cancer cell is evaluated by MTT assay.Protein level of p-AKT and p-mTOR is compared between the three groups in Western Blotting result.Results: Detection of TRβ1 protein verified the efficiency of transfection.MTT assay showed the proliferation of TRβ1-MDA and TRβ1-MCF is lower when compared with the other two.p-AKT and p-mTOR of TRβ1-MDA and TRβ1-MCF is inhibited.When the cells were incubated with T3,TRβ1-MDA and TRβ1-MCF showed a lower index of proliferation,accompanied by lowed expreeion of p-AKT and p-mTOR protein.Conclusion: TRβ1 can constrain growth of breast cancer cells via lowering activity of AKT/mTOR.Besides,this inhibition is T3-dependent,as constration of T3 is higher,pathway of AKT/mTOR is higher repressed.