自反馈调节环路E2F3/lncRNA-H19/miR-106a调控胶质瘤糖代谢和生长的机制

Tumor metabolism has become the hot topics in glioma research. Our data verified that E2F3 expression was significant lower in low grade gliomas compared to high grade gliomas, and higher E2F3 expression is associated with worse clinical outcome in glioma patients. Further, down-regulation of E2F3 inhibited glioma cell glycine metabolism and growth . We also found that E2F3 knockdown remarkably reduced lncRNA-H19 expression in glioma cells. Bioinformatics assays showed that there are miR-106a binding sites on the H19. Interestingly, down-regulation of H19 also reduced the expression of miR-106a target genes (E2F3) and inhibited glioma cell glycine metabolism. We speculated that H19 could regulated the H19 controled the expression of E2F3 by functioning as a competing endogenous RNA. Thus, we proposed the hypothesis that autoregulatory feedback loop of E2F3/H19/miR-106a plays a key role in glioma glycine metabolism and growth. In the future study, we will intend to establish E2F3/H19/miR-106a diverse expression of cell model, and take a serial of cell function experiments combined with the tests of transcriptional regulation, noncoding RNA regulation network and gene rescue as major methods, evaluate the effect of E2F3/H19/miR-106a feedback loop on glioma glycine metabolism and growth, further analyze the role of key notes in glioma molecular diagnosis, prognosis evaluation and targeting therapy. In conclusion, our finding will reveal the role and mechanism of E2F3/H19/miR-106a feedback loop in glioma glycine metabolism and growth, and provides more potential approaches for glioma treatment.

目前肿瘤细胞代谢调控已成为胶质瘤发病机制研究领域的新热点。我们前期研究发现：E2F3表达与胶质瘤恶性级别及患者预后密切相关。下调E2F3可抑制肿瘤细胞糖酵解水平，并引起lncRNA-H19表达降低。通过生物信息学分析提示H19上存在miR-106a的结合位点。下调H19表达还可降低miR-106a靶基因E2F3的表达。我们推测，H19可能通过“分子海绵”机制吸附miR-106a而影响其功能。据此我们提出假说：在胶质瘤的发病机制中存在E2F3/H19/miR-106a自反馈调控环路，三者相互作用调控肿瘤细胞的代谢。本课题拟建立E2F3/H19/miR-106a不同表达状态细胞模型并进行一系列细胞功能实验，转录调控和非编码RNA调控关系研究，深入探讨三者间相互调控关系及其在代谢过程中的作用机制，并为胶质瘤的早期预防和分子靶向治疗提供依据。

背景.胶质瘤是中枢神经系统中最常见的一种原发性肿瘤，大约80%的中枢神经系统恶性肿瘤是恶性胶质瘤。虽然针对胶质瘤的各种治疗在不断发展，但恶性胶质瘤的5年生存率仍然很低。目前认为，胶质瘤发病机制本质上是一种多基因、多个分子信号通路调节异常，从而使得肿瘤细胞表现出各种恶性表型。因此，从分子水平揭示胶质瘤发病的分子机制仍具有重大意义。.研究内容.1.分析E2F3、lncRNA-H19及miR-106a在胶质瘤中的表达及其对肿瘤细胞代谢的影响，并解析其在胶质瘤临床诊断及预后判断中的作用.2.明确胶质瘤中E2F3与lncRNA-H19之间的调控关系.3.明确E2F3是miR-106a的直接作用靶点.4.明确胶质瘤中 lncRNA-H19 对 miR-106a 的调控关系.5.荷瘤实验，在体验证体外实验结果.重要结果和关键数据.1. 和正常脑组织比较，胶质瘤组织中，E2F3、lncRNA-H19及miR-106a的表达均明显上调，且其表达与患者生存期存在相关性.2. 胶质瘤中，E2F3能调控lncRNA-H19的表达，并影响胶质瘤细胞的葡萄糖摄取、迁移和侵袭.3. 胶质瘤中，miR-106a能调控E2F3的表达，并影响胶质瘤细胞的葡萄糖摄取、迁移和侵袭.4. 胶质瘤中，lncRNA-H19能调控miR-106a的表达，并影响胶质瘤细胞的葡萄糖摄取、迁移和侵袭.5. 荷瘤实验表明，lncRNA-H19/mir-106a/E2F3能够影响胶质瘤的生长。.科学意义.经过本研究发现，E2F3能够调控lncRNA-H19的表达，从而与miR-106a构成反馈环路，调控胶质瘤葡萄糖代谢、迁移和侵袭。本研究明确了胶质瘤研究热点细胞代谢过程中转录因子（transcription factors，TFs）-lncRNA-miRNA调控环路之间的相互关系和作用机制，探索胶质瘤代谢过程中的分子调控新机制，初步描绘TFs-lncRNA-miRNA调控网络中三者的作用模式，为现有的神经胶质瘤发生发展机制提供补充，为临床神经胶质瘤的分子生物学诊断和预后判断提供理论依据，并为临床上胶质瘤的分子靶向治疗提供新依据。...。