microRNA与肿瘤机制.ppt

Effects of let-7 microRNA on Cell Growth and Differentiation of Papillary Thyroid Cancer Li Jianfang 2010-10-27 microRNA定义 microRNA定义 Development of microRNA miRNA的功能 miRNA的作用方式 研究miRNA的新工具 研究miRNA的新工具 Introduction Introduction Materials  Materials Methods  Results   expression of let-7f miRNA in PCCL3 Rat Thyroid Cells   expression of let-7f miRNA in PCCL3 Rat Thyroid Cells Results 1Doxycycline-Inducible Expression of RET/PTC3 in PCCL3 Rat Thyroid Cells Effects of let-7f on MAPK Signaling Pathway in TPC-1 Cells Effects of let-7f on MAPK Signaling Pathway in TPC-1 Cells Effects of let-7f on MAPK Signaling Pathway in TPC-1 Cells Growth Inhibitory Effect of let-7f miRNA on TPC-1 Cells Growth Inhibitory Effect of let-7f miRNA on TPC-1 Cells Results 3Growth Inhibitory Effect of let-7f Mature miRNA on TPC-1 Cells Effects of let-7f on Expression of Thyroid Differentiation Genes Results 3Growth Inhibitory Effect of let-7f Mature miRNA on TPC-1 Cells Discussion let-7f down-regulation let-7f down-regulation reduce cell growth reduce cell growth enhance expression of differentiation markers enhance expression of differentiation markers inhibitory effects on the MAPK pathway inhibitory effects on the MAPK pathway summary The let-7 family of miRNA includes 14 isomers; each isomer is typically located on a different chromosome [8]. This study focused on let-7f, because it has been previously shown to inhibit proliferation of lung cancer cells [29]. We observed a reduced expression of let-7f mature miRNA in PCCL3 cells with activation of RET/ PTC3. This suggests that let-7f down-regulation is an important step in the biologic effects mediated by the RET/ PTC oncogene. a previous study from patients with papillary carcinoma and normal thyroid tissues showed that let-7f is downregulated in this cancer [28]. To