MIIP 对膀胱癌 T24细胞增殖和迁移侵袭能力的抑制作用及其机制

目的：探讨迁移侵袭抑制蛋白（migration invasion inhibitory protein，MIIP）对膀胱癌 T24细胞增殖和迁移侵袭能力的影响及作用机制。方法：设计并合成 MIIP 过表达质粒，并利用脂质体转染方法上调 T24细胞系中 MIIP 的表达。Western blot 及实时定量聚合酶链反应（Real －time PCR）检测过表达 MIIP 的效果，四甲基偶氮唑蓝法（MTT）及平板克隆法观察 MIIP 过表达对 T24细胞增殖能力的影响，划痕及 Transwell 实验检验 MIIP过表达对 T24细胞迁移侵袭能力的影响。Western blot 及 Real －time PCR 检测过表达 MIIP 后其上皮间充质转化（epithelial －mesenchymal transition，EMT）过程相关标志物钙黏蛋白 E（E －cadherin）、钙连蛋白 N（N －cadherin）、转录因子 Snail 蛋白和 mRNA 变化情况。结果：过表达质粒能有效上调 T24细胞系中 MIIP 蛋白及mRNA 的表达，上调 MIIP 表达后 T24细胞增殖能力明显下降，克隆形成能力下降，迁移侵袭能力减弱；上调MIIP 表达后 E －cadherin 表达增加，N －cadherin 及转录因子 Snail 表达减少。结论：过表达 MIIP 可能通过降解转录因子 Snail，从而抑制 EMT 进程降低膀胱癌 T24细胞的增殖及迁移侵袭能力。

The mechanism of MIIP inhibiting proliferation and migration invasion in bladder cancer T24 cells

Objective:To investigate the mechanism of migration invasion inhibitory protein(MIIP)inhibiting pro-liferation and migration invasion abilities of T24 cells.Methods:To design and synthesize the MIIP over -expression plasmid P -CMV4 -MIIP.Plasmids were transfected into T24 cells and the effects were detected by Western blot and Real -time PCR.The proliferation abilities were tested by MTT assay and colony formation assay.The wound scratch assay and Transwell chamber assay were used to test the migration and invasion abilities.The expression levels of epi-thelial -mesenchymal transition(EMT)related molecules E -cadherin,N -cadherin and Snail were detected by Western blot and Real -time PCR.Results:P -CMV4 -MIIP could effectively up -regulate the expression of MIIP in T24 cells.Up -regulation of MIIP expression can suppress the cell proliferation and migration invasion capacity of the T24 cells.In addition,the expression of E -cadherin was up -regulated while N -cadherin and Snail were down-regulated when MIIP was increased.Conclusion:MIIP overexpression can inhibit the proliferation and migration in-vasion capacities by degradation Snail and hindering EMT process in T24 cells.