Role of de Novo Synthesis of Sphingolipids in Aneuploid Cells

鞘脂从头合成在非整倍体细胞中的作用

• 批准号: 10084296
• 负责人: Eduardo Martin Torres
• 金额: $ 33.08万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10084296
• 关键词: Affect; Anabolism; Aneuploid Cells; Aneuploidy; Cell Cycle; Cell Cycle Arrest; Cell physiology; Cells; Ceramides; Chromosomes; Clinic; Clinical; DNA Sequence Alteration; Data; Dependence; Development; Disease; Down Syndrome; Drug Targeting; Drug Utilization; Enzymes; Equilibrium; Eukaryota; Gene Deletion; Gene Expression; Genes; Growth; Human; Intellectual functioning disability; Lead; Lipids; Literature; Malignant Neoplasms; Metabolic; Metabolic Pathway; Metabolism; Molecular; Mutation; Neurodegenerative Disorders; Normal Cell; Pathway interactions; Phenotype; Phosphoric Monoester Hydrolases; Phosphotransferases; Physiological; Play; Process; Prognosis; Proliferating; Proteins; Proteome; Regulation; Role; Series; Serine; Signal Pathway; Signaling Molecule; Sphingolipids; Sphingosine; Stress; Tumor Biology; Yeasts; anti-cancer; cancer cell; cancer type; chromosome number abnormality; fitness; genetic approach; human disease; improved; insight; lipid metabolism; novel; pressure; proteotoxicity; response; serine palmitoyltransferase; tumor

Abstract Aneuploidy, a cellular state of having an abnormal number of chromosomes, is a hallmark of cancer. The degree of aneuploidy significantly correlates with tumor aggressiveness and poor clinical prognosis. Therefore, studying the cellular processes affected by aneuploidy can improve our understanding of the role of aneuploidy in tumor biology. Our preliminary results show that de novo synthesis of sphingolipids is increased by aneuploidy; we therefore propose to identify the molecular mechanisms underlying this effect. Targeting the synthesis of sphingolipids holds great potential as an anti-cancer strategy that could be used either alone or in combination with existing therapies. Despite the existence of a large body of literature providing strong evidence for the misregulation of sphingolipid metabolism in human diseases, including several types of cancers, the molecular mechanisms that lead to this misregulation are poorly understood. The focus of this proposal is to unravel the molecular mechanisms that regulate de novo synthesis of sphingolipids and to decipher how these mechanisms are affected in aneuploid cells. To this end, we propose to: (1) Determine how aneuploidy increases sphingolipid biosynthesis. Our preliminary data supports the hypothesis that aneuploid cells rely on the increased activity of serine palmitoyltransferase, the enzyme that controls the first and irreversible step of sphingolipid synthesis, to proliferate. Therefore, we will investigate the function of signaling pathways that regulate serine palmitoyltransferase in aneuploidy. In addition, because serine serves as a precursor for sphingolipids, we will investigate whether aneuploidy leads to increased serine utilization. To that end, we plan to quantify serine metabolic flux through the sphingolipid pathway in aneuploid cells. Our studies will provide novel insights into how sphingolipid synthesis is affected in response to aneuploidy. (2) Determine how sphingolipid levels control the fitness of aneuploid cells. Our preliminary results show that mutations in four different genes that increase the levels of sphingosine and lower those of ceramide, improve the fitness of aneuploid cells. Therefore, we will determine, in aneuploid cells, the function of Pkh1/2 kinases and Cdc55 phosphatase because these signaling molecules are known to act downstream of sphingolipids and regulate the cell cycle and responses to stress. In addition, we will determine specific cellular pathways and processes that play an important role in overcoming the detrimental effects of aneuploidy. Gene expression, proteome content, and phenotypic analyses in combination with genetic approaches will be used to accomplish this aim. Altogether, our studies will contribute to a better understanding of the physiological role of sphingolipids in controlling the fitness of aneuploid cells. Determining the mechanisms that control the fitness of aneuploid cells can be exploited to target aneuploid cancer cells and to ameliorate the deleterious effects of aneuploidy in Down syndrome or neurodegenerative diseases.

抽象的 非整倍性是染色体数量异常的细胞状态，是癌症的标志。这 非整倍性程度与肿瘤侵袭性和临床预后不良显着相关。所以， 研究受非整倍性影响的细胞过程可以提高我们对非整倍性作用的理解 在肿瘤生物学中。我们的初步结果表明，从头合成鞘脂的合成是通过 非整倍性；因此，我们建议确定这种作用的分子机制。定位 鞘脂的合成具有巨大的潜力，可以单独或在 结合现有疗法。尽管存在大量文学作品 人类疾病中鞘脂代谢的不正调的证据，包括几种类型的 癌症是导致这种正调的分子机制的理解不足。重点 建议是阐明调节鞘脂从头合成的分子机制和 破译这些机制如何在非整倍体细胞中影响。为此，我们建议：（1）确定 非整倍性如何增加鞘脂生物合成。我们的初步数据支持以下假设 非整倍体细胞依赖于丝氨酸棕榈酰转移酶的活性增加，这是控制第一个的酶 鞘脂合成的不可逆转步骤，以增殖。因此，我们将研究 信号传导途径，调节丝氨酸棕榈酰转移酶在非整倍型中。另外，因为丝氨酸服务 作为鞘脂的前体，我们将研究非整倍性是否导致丝氨酸利用率增加。到 那一端，我们计划通过非整倍体细胞中的鞘脂途径来量化丝氨酸代谢通量。我们的 研究将提供有关鞘脂合成如何影响非整倍性的新见解。 （2） 确定鞘脂水平如何控制非整倍体细胞的适应性。我们的初步结果表明 四个不同基因的突变增加了鞘氨醇水平并降低神经酰胺的水平，改善 非整倍体细胞的适应性。因此，我们将在非整倍体细胞中确定PKH1/2激酶的功能 和Cdc55磷酸酶，因为已知这些信号分子在鞘脂和下游作用 调节细胞周期和对压力的反应。此外，我们将确定特定的细胞途径和 在克服非整倍性的有害影响方面起着重要作用的过程。基因表达， 蛋白质组含量和表型分析将与遗传方法结合使用来完成 这个目标。总之，我们的研究将有助于更好地理解 鞘脂在控制非整倍体细胞的适应性方面。确定控制健身的机制 可以利用非整倍体细胞靶向非整倍性癌细胞，并改善 唐氏综合症或神经退行性疾病的非整倍性。

项目成果

Consequences of aneuploidy in human fibroblasts with trisomy 21.

• DOI: 10.1073/pnas.2014723118
• 发表时间: 2021-02-09
• 期刊: Proceedings of the National Academy of Sciences of the United States of America
• 影响因子: 11.1
• 作者: Hwang S;Cavaliere P;Li R;Zhu LJ;Dephoure N;Torres EM
• 通讯作者: Torres EM