HMGB1调控hTERT表达在肺癌发生发展中的作用及研究

The development of lung cancer is a complex process with multiple genes altered. High mobility group protein 1 (HMGB1) is a non-histone chromosomal binding protein in eukaryotic cells, plays an important role in the tumor malignant tranformation. Our previous study manifested that HMGB1 overexpressed in lung cancer specimens and was associated with the prognosis of lung cancer. Preliminary studies indicated that HMGB1 was positively correlated with telomere length and hTERT expression. Inhibiting the expression of HMGB1 would make for the downregulation of hTERT expression and reducing of the promoter activity, it suggested that HMGB1 regulated hTERT expression at the transcriptional level. Therefore, we speculate that it is worth discussing of exact mechanism of HMGB1 to promote lung cancer occurance and its role in the regulation of hTERT. This research intends to observe the impact of HMGB1 gene on hTERT expression, activity and the biological function of lung cancer using RNA interference and cell transfection technique. Then we will explore the regulatory mechanism of HMGB1 on hTERT expression and the development of lung cancer by detecting the promoter luciferase activity, EMSA and CHIP experiments in vitro or experiments in vivo. Finally, we will detect HMGB1 and hTERT expression and its correlationship in lung cancer tissues and summarize the specific regulatory mechanism of HMGB1 on hTERT expression and the clinical significance for the development of lung cancer by analyzing the clinical and prognostic information.The completion of this project will lay the foundation of HMGB1and telomere for the research of tumor treatment, provide a potential new therapeutic strategies for regulational mechanism of HMGB1 and hTERT.

高迁移率族蛋白1(HMGB1)是存在于真核生物细胞内的非组蛋白染色体结合蛋白，在肿瘤恶性演变过程中扮演重要角色。前期预实验发现，肺癌标本HMGB1过表达，且与肺癌预后相关；HMGB1与端粒长度和hTERT表达正相关；抑制HMGB1表达，hTERT启动子活性降低，提示HMGB1在转录水平调控hTERT。因此，在肺癌恶性转过程中，HMGB1促进肺癌发生发展的分子机制以及HMGB1调控hTERT的具体机制值得探讨。本项目拟通过RNA干扰和转染技术，观察HMGB1基因对hTERT表达、活性及对肺癌生物学功能的影响；进一步通过启动子荧光素酶活性、EMSA和CHIP实验，探讨HMGB1对hTERT的调控机制，通过体内实验和大病历肺癌组织探讨HMGB1调控hTERT及其在肺癌发生发展中的作用。本课题的完成，为以HMGB1和端粒为靶点的肿瘤研究打下基础，为揭示HMGB1和hTERT调控肺癌机制提供新思路。

高迁移率族蛋白1（HMGB1）是真核细胞中重要的染色质结合蛋白，具有维持染色质结构的功能，且参与多种肿瘤的发生发展。本课题研究表明，HMGB1与组蛋白乙酰化相关蛋白SET和HAT1存在相互作用;HMGB1敲低的肺癌细胞系组蛋白乙酰化水平明显升高，提示其可能具有组蛋白乙酰化的调控能力; HMGB1特异性乙酰化H3K9和H3K27位点调控肺癌细胞组蛋白乙酰化；通过ChIP-seq对HMGB1与SET和HAT1形成复合物调控组蛋白乙酰化的机制进行阐述；并对其转录调控靶基因进行筛选；最终通过体内外实验以及临床标本对HMGB1转录调控通路在肺癌中的作用予以验证。本课题的完成，将揭示HMGB1调控组蛋白乙酰化并参与转录调控的分子机制，为以HMGB1为靶点的肿瘤研究提供新的思路。