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: 9238913
• 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 2021-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9238913
• 关键词: Affect; Anabolism; Aneuploid Cells; Aneuploidy; Cell Cycle; Cell Cycle Arrest; Cell physiology; Cells; Ceramides; Chromosomes; Clinic; Clinical; DNA Sequence Alteration; Data; Dependency; 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; Proliferating; Proteins; Proteome; Regulation; Role; Series; Serine; Signal Pathway; Signaling Molecule; Sphingolipids; Sphingosine; Stress; Tumor Biology; Yeasts; cancer cell; cancer type; chromosome number abnormality; fitness; genetic approach; human disease; improved; insight; lipid metabolism; novel; outcome forecast; 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.

摘要 非整倍性，一种染色体数目异常的细胞状态，是癌症的标志。的 异倍体的程度与肿瘤的侵袭性和不良的临床预后显著相关。因此，我们认为， 研究受非整倍体影响的细胞过程可以提高我们对非整倍体作用的理解 在肿瘤生物学中。我们的初步结果表明，鞘脂的从头合成增加， 非整倍体;因此，我们建议确定这种影响的分子机制。针对 鞘脂的合成具有作为抗癌策略的巨大潜力， 与现有的治疗方法相结合。尽管有大量的文献提供了强大的 人类疾病中鞘脂代谢失调的证据，包括几种类型的 癌症，导致这种失调的分子机制知之甚少。的重点 该提案旨在阐明调节鞘脂从头合成的分子机制， 破译这些机制是如何在非整倍体细胞中受到影响的。为此，我们建议：（1）确定 非整倍体如何增加鞘脂生物合成。我们的初步数据支持这一假设， 非整倍体细胞依赖于丝氨酸棕榈酰转移酶活性的增加，这种酶控制着第一个 和鞘脂合成的不可逆步骤，增殖。因此，我们将研究 在非整倍体中调节丝氨酸棕榈酰转移酶的信号通路。此外，由于丝氨酸 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增加。到 为此，我们计划在非整倍体细胞中量化通过鞘脂途径的丝氨酸代谢通量。我们 这些研究将为非整倍体如何影响鞘脂合成提供新的见解。（二） 确定鞘脂水平如何控制非整倍体细胞的适应性。我们的初步结果显示， 四种不同基因的突变增加了鞘氨醇的水平，降低了神经酰胺的水平， 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Pkh 1/2激酶的功能， 和Cdc 55磷酸酶，因为已知这些信号分子作用于鞘脂的下游， 调节细胞周期和应激反应。此外，我们将确定特定的细胞通路， 这些过程在克服非整倍性的有害影响中起重要作用。基因表达， 蛋白质组含量和表型分析与遗传方法相结合将用于完成 这个目标。总之，我们的研究将有助于更好地理解的生理作用， 鞘脂在控制非整倍体细胞适应性中的作用。确定控制适应性的机制 可以利用非整倍体细胞来靶向非整倍体癌细胞并改善非整倍体癌细胞的有害作用。 唐氏综合征或神经退行性疾病中的非整倍体。