中文摘要：

目的：研究Id3的表达在口腔鳞状细胞癌侵袭转移中的作用机制。方法：在UM-SCC-23口腔鳞状细胞癌中瞬时转染Id3真核表达载体,实时PCR和蛋白印迹法检测Id3和E-cadherin在基因和蛋白水平的表达。将E-cadherin启动子载体瞬时转染到UM-SCC-23细胞系中,利用荧光双报告基因系统检测Id3对E-cadherin启动子的调控作用。利用Id3稳定转染UM-SCC-23细胞系进行细胞侵袭实验。结果：Id3促进了E-cadherin基因和蛋白水平的表达,增强了E-cadherin启动子活性,稳定表达Id3的UM-SCC-23细胞系侵袭能力降低。结论：Id3能够促进E-cadherin表达,抑制口腔鳞状细胞癌的侵袭。

英文摘要：

Objective： To investigate the role of Id3 in human squamous cell carcinoma.Methods： The Id3 expression vectors and control vectors were transiently transfected into UM-SCC-23 cells of human squamous cell carcinoma cell by Lipofectamine 2000TM,respectively. The mRNA and protein levels of Id3 and E-cadherin in UM-SCC-23 cells were detected by real-time polymerase chain reaction and Western blotting.UM-SCC-23 cells were transiently transfected with the E-cadherin promoter-reporter plasmid and we investigated the effect of Id3 on E-cadherin promoter activity in Dual Luciferase Reporter Assay System.Transwell cell migration assays were performed with Id3 stable cell lines.Results： Id3 up-regulated E-cadherin mRNA and protein levels.The Id3 enhanced the E-cadherin promoter activity. Id3 stable transfection UM-SCC-23 cells inhibited UM-SCC-23 cell invasion by cell invasion assay.Conclusion： This study suggests that Id3 increase the expression of E-cadherin and inhibit the invasion of human squamous cell carcinoma.