NCOA3上调端粒酶逆转录酶促进肝癌生长的分子机制及其临床意义

High expression of human telomerase reverse transcriptase (hTERT) is an important feature in the malignances development。Discovery cancer-specifit regulatory factors of hTERT is critically significant. Previously, we identified a new hTERT promoter binding protein, NCOA3 in liver cancer cells by DNA binding protein pulldown techniques and proteomics approach, and showed that its high expression in liver cancer cells, and its regulation of hTERT transcription and cell growth and apoptosis of liver cancer. However, how NCOA3 regulates hTERT, which in turn affects the tumorigenesis and progression of liver cancer and its clinical relevance, is not clear. In this study, we will knock-down and overexpress NCOA3 in the liver cancer cells and animal models, to study its regulation in the expression of hTERT, promoter activity and telomerase activity and the effect on tumor growth, to reveal the role of the NCOA3/hTERT signaling pathway in the development of liver cancer and the underlying molecular mechanism. In addition, using tissue microarray and clinical data, we will analyse the expression level of the NCOA3/hTERT and their correlation in liver cancer tissues, and assess its relationship with the stage, recurrence and prognosis to clarify the clinical significance. This project will provide theoretical and experimental basis for establishing NCOA3 as a new target for liver cancer treatment.

人端粒酶逆转录酶hTERT高表达是肿瘤发生发展的重要指标，发现肿瘤特异性hTERT调控因子意义重大。前期，我们利用DNA结合蛋白垂钓技术和蛋白质组学方法，在肝癌细胞中垂钓和确定了一个新的hTERT启动子结合蛋白NCOA3，并证实其在肝癌细胞中高表达、可调控hTERT转录和肝癌细胞生长和凋亡，但NCOA3如何调控hTERT继而影响肝癌发生发展的分子机制及其临床意义，目前尚不清楚。本项目拟在肝癌细胞和动物模型中敲低或过表达NCOA3，研究其对hTERT表达、启动子活性和端粒酶功能活性的调控及对肿瘤生长的影响，揭示NCOA3/hTERT信号通路在肝癌发生发展中的作用和分子机制；并利用组织芯片，结合临床资料，分析肝癌组织中NCOA3/hTERT的表达水平及两者的相关性，并评估其与肝癌发生、分期、复发、预后的关系，明确其临床意义。本项目将为确立NCOA3作为肝癌治疗新靶点提供理论和实验依据。

人端粒酶逆转录酶hTERT高表达是肿瘤发生发展的重要指标，但其在肝癌中高表达的分子机理不是很清楚。为此，我们利用DNA结合蛋白垂钓技术和蛋白质组学方法，在肝癌细胞中发现了一个新的hTERT启动子结合蛋白NCOA3，并证实其在肝癌细胞中高表达。NCOA3可调控hTERT的转录、肝癌细胞生长和凋亡与肿瘤干细胞的干性。进一步的机制研究发现NCOA3可与SP1相互作用并协同促进TERT转录和表达，进而促进肝癌细胞增殖和肿瘤生长。在体内，阻断NCOA3或者SP1可以明显抑制肿瘤生长。临床样本上我们也发现NCOA3、SP1和TERT高表达的患者具有较短的生存期，其高表达可以预测不良预后。本项目揭示了肝癌治中TERT高表达的分子机理，明确了NCOA3与SP1互作协同促进TERT高表达促进肝癌发生发展的功能和作用机理。明确了NCOA3、SP1和TERT表达在肝癌临床病理中的意义和运用价值。为肝癌的临床诊断和治疗提供了潜在的分子标记物和治疗靶点。在项目资金的支持下我们共发表了5篇SCI文章，培养了1名硕士研究生。