膜蛋白介导受IRES调控的cyclin B1促进食管癌转移的作用机制研究

Esophageal cancer is a comment type of cancer in China. Metastasis is the major cause of death in esophageal cancer. Our previous work demonstrates that the cell cycle protein cyclin B1 was overexpressed in esophageal cancer (The copy number and the mRNA level have no difference with the normal tissue).The ectopic expression of cyclin B1 promoted the lung matastasis of esophageal cancer cells in nude mice. We found one protein associated with the expression of cyclin B1 named Protein X by using the strategy of "systematic evolution of ligands by exponential enrichment (SELEX)". Protein X was also overexpressed in esophageal cancer. Protein X siRNA could affect the growth rate, invasive and migration ability of esophageal cancer cells. However the mechanisms of cyclin B1 overexpression in esophageal cancer are still not clear. The role of Protein X in the development of esophageal cancer and the association between Protein X and cyclin B1 haven't been reported. We will reveal the regulation of expression of cyclin B1 by evaluating the internal ribosome entry site activity of cyclin B1 through bicistronic fluorescent experiment. And we will investigate the function of Protein X in the growth and metastasis of esophageal cancer in the cell level and molecular level. Co-Immunoprecipitation experiment and mass spectrometry will be used to reveal the relationship between Protein X and cyclin B1. At last we will measure the expression level of Protein X in the tumor tissue and the serum. Our work has important theoretic implication and application value in esophageal cancer development and therapy.

远端转移是食管癌致死的主要原因，我们前期研究发现cyclinB1在食管癌中高表达（基因拷贝数与mRNA水平无变化）并促进食管癌细胞体内肺转移,通过指数式富集配体系统进化筛选到与cyclin B1相关膜蛋白Protein X。Protein X在食管癌中高表达，敲降Protein X抑制食管癌细胞增殖侵袭与迁移。但cyclin B1蛋白在食管癌中高表达的机制、Protein X在cyclin B1促进食管癌肺转移中的作用及调控机制尚不明确。本项目拟采用双顺反子荧光报告实验检测cyclin B1内部核糖体进入位点（IRES）的调控，探讨cyclin B1转录翻译水平不一致的机制。利用肺内皮迁移实验等手段研究Protein X的生物学功能及其与食管癌转移的关系。采用免疫共沉淀、磷酸化质谱等方法研究cyclin B1与Protein X的的调控关系，在肿瘤组织、血液中分析评价二者的临床意义。

远端转移是食管癌致死的主要原因，我们前期研究发现cyclinB1 在食管癌中高表达（基因拷贝数与mRNA 水平无变化）并促进食管癌细胞体内肺转移,通过指数式富集配体系统进化筛选到与cyclin B1 相关膜蛋白Protein X。Protein X 在食管癌中高表达，敲降Protein X 抑制食管癌细胞增殖侵袭与迁移。但cyclin B1 蛋白在食管癌中高表达的机制、Protein X 在cyclin B1 促进食管癌肺转移中的作用及调控机制尚不明确。本项目采用双顺反子荧光报告实验确定了cyclin B1 内部核糖体进入位点（IRES）的调控，探讨cyclin B1转录翻译水平不一致的机制。采用免疫共沉淀、磷酸化质谱等方法阐明cyclin B1 与Protein X 的调控关系，并在肿瘤组织、血液中探索了二者的临床意义。本项目为食管癌的定向转移提供了新的思路。