在星形胶质瘤等几种组织肿瘤细胞中，Lrig1作为抑癌基因通过在细胞膜上干扰EGFR的活性从而抑制肿瘤生长；但在肿瘤细胞浆中Lrig1作为原癌基因调控抑癌基因PTEN表达的分子机制尚未见报道。本项目拟在食管癌细胞株Eca109、KYSE450和TE-1中过表达Lrig1，应用绿色荧光蛋白融合表达法或免疫荧光技术确定Lrig1蛋白在细胞中的定位，采用qRT-PCR和Western blot方法及细胞内信号传导通路抑制剂明确Lrig1对PTEN表达的影响与可能参与调控的主要信号通路，应用流式细胞仪检测过表达Lrigl对细胞周期和细胞凋亡的影响，最终确定Lrig1作为原癌基因在肿瘤细胞的高表达对细胞周期、凋亡的影响，以及为探索其对PTEN表达调控的分子机制奠定实验基础。

Leucine-rich repeats and immunoglobulin like domains 1 (Lrig1) is a cell surface protein of being able to decrease the activity of EGFR,but in the cytoplasm of tumor cells,the molecular mechanism of Lrig1 as proto-oncogene regulates the expression of PTEN has not been reported. The project intends to overexpression of Lrig1 in esophageal cancer cell lines 109,KYSE450 and TE-1 using green fluorescent protein fusion construct or immunofluorescence to determine the localization of Lrig1 protein in the cell, using the methods of qRT-PCR,Western blot,and intracellular signal transduction pathway inhibitors to study the effects of Lrig1 on PTEN's expression and the possible signaltransduction pathway. Then detect the effects of Lrig1 on the cell cycle and apoptosis by flow cytometry. All together to evaluate the effects of high expression of Lrig1 as an oncogene on cell cycle, apoptosis, and provide the experimental basis on the molecular mechanism of the regulation of PTEN expression.