GLS1通过调节组蛋白乙酰化修饰促进AML细胞脂质合成和细胞增殖的机制研究

Glutamic enzyme 1 (GLS1) is involved in tumor metabolic reprogramming and is closely related to the occurrence and development of various tumors. However, the function and mechanism of GLS1 in acute myeloid leukemia (AML) is not enough understood. Our previous study found that GLS1 is highly expressed in AML. Overexpression of GLS1 can promote lipid synthesis and cell proliferation in AML cells, while lipid synthesis related genes ACC2 and FASN are significantly up-regulated, while knockdown of GLS1 in AML cells decrease the expression of acetyl-CoA and the level of acetyl-histone H3. To this end, we hypothesized that GLS1 may promote the lipid synthesis and cell proliferation of AML cells by increasing the level of histone H3 acetylation in the promoter regions of ACC2 and FASN, then activating transcription of ACC2 and FASN. This project intends to use immunoblotting, 14C isotope labeling and tracer, ChIP-qPCR and other methods to explore the molecular mechanism of GLS1 promoting lipid synthesis and cell proliferation of AML cells from cell, animal model and clinical level, and ultimately providing new strategies and experimental basis for the accurate treatment of AML.

谷氨酰胺酶1（GLS1）参与肿瘤代谢重编程，与多种肿瘤的发生发展密切相关，但GLS1在急性髓系白血病（AML）中的作用及机制尚不完全清楚。我们前期研究发现GLS1在AML中高表达，过表达GLS1可促进AML细胞脂质合成及细胞增殖，同时脂质合成相关基因ACC2和FASN表达显著上调，而下调GLS1后乙酰辅酶A及组蛋白H3乙酰化水平显著降低。为此我们设想：GLS1可能通过提高ACC2和FASN启动子区域组蛋白H3乙酰化水平，激活ACC2和FASN基因转录，从而促进 AML 细胞脂质合成和细胞增殖。本项目拟采用免疫印迹、14C同位素标记示踪、ChIP-qPCR等方法从细胞、动物模型及临床水平深入探索GLS1促进AML细胞脂质合成和细胞增殖的分子机制，为AML的精准治疗提供新策略和实验依据。

肿瘤代谢及肿瘤表观遗传是肿瘤发生发展的重要特征，深入研究肿瘤代谢及肿瘤表观遗传对肿瘤防治、提高患者长期生存具有重要的临床意义。谷氨酰胺酶1（GLS1）参与肿瘤代谢重编程，与多种肿瘤的发生发展密切相关，但GLS1在 急性髓系白血病（AML）中的作用及机制尚不完全清楚。本项目利用AML细胞株KG1a和KASUMI细胞为研究对象，构建GLS1稳定敲低慢病毒载体，首先证实了敲低GLS1能有效抑制AML细胞增殖和克隆形成，并诱导AML细胞凋亡。同时，敲低 GLS1能有效诱导AML细胞ROS产生及线粒体膜电位改变。机制上，通过转录组测序分析发现，敲低 GLS1可能与信号通路PI3K-Akt和Rap1信号通路相关。同时对差异基因进行分析，发现敲低GLS1抑制CD52表达。此外，肿瘤代谢与肿瘤表观遗传在肿瘤发生发展中的作用举足轻重，故进行了延伸和拓展，研究了影响肿瘤代谢的药物HMG-CoA还原酶抑制剂辛伐他汀在白血病临床前模型中的抗白血病作用以及探讨了表观遗传调控因子RNA m6A甲基化阅读子YTHDF2在实体瘤肺腺癌增殖转移中的作用。为肿瘤代谢和肿瘤表观遗传在肿瘤中的应用提供新的思路与方法，对将来临床应用奠定理论和实验基础。