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Science (New York, N.Y.) May 2009In contrast to normal differentiated cells, which rely primarily on mitochondrial oxidative phosphorylation to generate the energy needed for cellular processes, most... (Review)
Review
In contrast to normal differentiated cells, which rely primarily on mitochondrial oxidative phosphorylation to generate the energy needed for cellular processes, most cancer cells instead rely on aerobic glycolysis, a phenomenon termed "the Warburg effect." Aerobic glycolysis is an inefficient way to generate adenosine 5'-triphosphate (ATP), however, and the advantage it confers to cancer cells has been unclear. Here we propose that the metabolism of cancer cells, and indeed all proliferating cells, is adapted to facilitate the uptake and incorporation of nutrients into the biomass (e.g., nucleotides, amino acids, and lipids) needed to produce a new cell. Supporting this idea are recent studies showing that (i) several signaling pathways implicated in cell proliferation also regulate metabolic pathways that incorporate nutrients into biomass; and that (ii) certain cancer-associated mutations enable cancer cells to acquire and metabolize nutrients in a manner conducive to proliferation rather than efficient ATP production. A better understanding of the mechanistic links between cellular metabolism and growth control may ultimately lead to better treatments for human cancer.
Topics: Adenosine Triphosphate; Aerobiosis; Amino Acids; Animals; Cell Proliferation; Glucose; Glycolysis; Humans; Lipids; Metabolic Networks and Pathways; Mutation; Neoplasms; Nucleotides; Oxidative Phosphorylation; Signal Transduction
PubMed: 19460998
DOI: 10.1126/science.1160809 -
Nature Reviews. Cancer May 2023Metabolic alterations are a key hallmark of cancer cells, and the augmented synthesis and use of nucleotide triphosphates is a critical and universal metabolic... (Review)
Review
Metabolic alterations are a key hallmark of cancer cells, and the augmented synthesis and use of nucleotide triphosphates is a critical and universal metabolic dependency of cancer cells across different cancer types and genetic backgrounds. Many of the aggressive behaviours of cancer cells, including uncontrolled proliferation, chemotherapy resistance, immune evasion and metastasis, rely heavily on augmented nucleotide metabolism. Furthermore, most of the known oncogenic drivers upregulate nucleotide biosynthetic capacity, suggesting that this phenotype is a prerequisite for cancer initiation and progression. Despite the wealth of data demonstrating the efficacy of nucleotide synthesis inhibitors in preclinical cancer models and the well-established clinical use of these drugs in certain cancer settings, the full potential of these agents remains unrealized. In this Review, we discuss recent studies that have generated mechanistic insights into the diverse biological roles of hyperactive cancer cell nucleotide metabolism. We explore opportunities for combination therapies that are highlighted by these recent advances and detail key questions that remain to be answered, with the goal of informing urgently warranted future studies.
Topics: Humans; Neoplasms; Nucleotides; Energy Metabolism
PubMed: 36973407
DOI: 10.1038/s41568-023-00557-7 -
Nucleic Acids Research Feb 2015Nucleotides are required for a wide variety of biological processes and are constantly synthesized de novo in all cells. When cells proliferate, increased nucleotide... (Review)
Review
Nucleotides are required for a wide variety of biological processes and are constantly synthesized de novo in all cells. When cells proliferate, increased nucleotide synthesis is necessary for DNA replication and for RNA production to support protein synthesis at different stages of the cell cycle, during which these events are regulated at multiple levels. Therefore the synthesis of the precursor nucleotides is also strongly regulated at multiple levels. Nucleotide synthesis is an energy intensive process that uses multiple metabolic pathways across different cell compartments and several sources of carbon and nitrogen. The processes are regulated at the transcription level by a set of master transcription factors but also at the enzyme level by allosteric regulation and feedback inhibition. Here we review the cellular demands of nucleotide biosynthesis, their metabolic pathways and mechanisms of regulation during the cell cycle. The use of stable isotope tracers for delineating the biosynthetic routes of the multiple intersecting pathways and how these are quantitatively controlled under different conditions is also highlighted. Moreover, the importance of nucleotide synthesis for cell viability is discussed and how this may lead to potential new approaches to drug development in diseases such as cancer.
Topics: Animals; Cell Cycle; DNA; Humans; Metabolic Networks and Pathways; Mice; Nucleotides; RNA
PubMed: 25628363
DOI: 10.1093/nar/gkv047 -
Cell Feb 2017Transformed cells adapt metabolism to support tumor initiation and progression. Specific metabolic activities can participate directly in the process of transformation... (Review)
Review
Transformed cells adapt metabolism to support tumor initiation and progression. Specific metabolic activities can participate directly in the process of transformation or support the biological processes that enable tumor growth. Exploiting cancer metabolism for clinical benefit requires defining the pathways that are limiting for cancer progression and understanding the context specificity of metabolic preferences and liabilities in malignant cells. Progress toward answering these questions is providing new insight into cancer biology and can guide the more effective targeting of metabolism to help patients.
Topics: Adenosine Triphosphate; Animals; Cell Proliferation; Cell Transformation, Neoplastic; Citric Acid Cycle; Humans; Metabolic Networks and Pathways; NADP; Neoplasms; Nucleotides
PubMed: 28187287
DOI: 10.1016/j.cell.2016.12.039 -
Frontiers in Endocrinology 2021The mechanisms of epigenetic gene regulation-histone modifications, chromatin remodeling, DNA methylation, and noncoding RNA-use metabolites as enzymatic cofactors and... (Review)
Review
The mechanisms of epigenetic gene regulation-histone modifications, chromatin remodeling, DNA methylation, and noncoding RNA-use metabolites as enzymatic cofactors and substrates in reactions that allow chromatin formation, nucleotide biogenesis, transcription, RNA processing, and translation. Gene expression responds to demands from cellular processes that use specific metabolites and alters or maintains cellular metabolic status. However, the roles of metabolites-particularly nucleotides-as regulatory molecules in epigenetic regulation and biological processes remain largely unknown. Here we review the crosstalk between gene expression, nucleotide metabolism, and cellular processes, and explore the role of metabolism in epigenetics as a critical regulator of biological events.
Topics: Animals; Chromatin; Chromatin Assembly and Disassembly; Epigenesis, Genetic; Gene Expression; Histones; Humans; Nucleotides; Protein Processing, Post-Translational
PubMed: 34526971
DOI: 10.3389/fendo.2021.731648 -
Nature Communications Jan 2019Under hypoxia, most of glucose is converted to secretory lactate, which leads to the overuse of glutamine-carbon. However, under such a condition how glutamine nitrogen...
Under hypoxia, most of glucose is converted to secretory lactate, which leads to the overuse of glutamine-carbon. However, under such a condition how glutamine nitrogen is disposed to avoid over-accumulating ammonia remains to be determined. Here we identify a metabolic flux of glutamine to secretory dihydroorotate, which is indispensable to glutamine-carbon metabolism under hypoxia. We found that glutamine nitrogen is necessary to nucleotide biosynthesis, but enriched in dihyroorotate and orotate rather than processing to its downstream uridine monophosphate under hypoxia. Dihyroorotate, not orotate, is then secreted out of cells. Furthermore, we found that the specific metabolic pathway occurs in vivo and is required for tumor growth. The identified metabolic pathway renders glutamine mainly to acetyl coenzyme A for lipogenesis, with the rest carbon and nitrogen being safely removed. Therefore, our results reveal how glutamine carbon and nitrogen are coordinatively metabolized under hypoxia, and provide a comprehensive understanding on glutamine metabolism.
Topics: Acetyl Coenzyme A; Ammonia; Animals; Carbon; Cell Hypoxia; Cell Line, Tumor; Cell Survival; Female; Glucose; Glutamine; HEK293 Cells; Humans; Lactic Acid; Lipogenesis; Metabolic Networks and Pathways; Metabolome; Metabolomics; Mice; Mice, Nude; Neoplasms; Nitrogen; Nucleotides; Orotic Acid; Tumor Microenvironment; Xenograft Model Antitumor Assays
PubMed: 30643150
DOI: 10.1038/s41467-018-08033-9 -
Cold Spring Harbor Perspectives in... Aug 2016Second messengers are small molecules and ions that relay signals received by cell-surface receptors to effector proteins. They include a wide variety of chemical... (Review)
Review
Second messengers are small molecules and ions that relay signals received by cell-surface receptors to effector proteins. They include a wide variety of chemical species and have diverse properties that allow them to signal within membranes (e.g., hydrophobic molecules such as lipids and lipid derivatives), within the cytosol (e.g., polar molecules such as nucleotides and ions), or between the two (e.g., gases and free radicals). Second messengers are typically present at low concentrations in resting cells and can be rapidly produced or released when cells are stimulated. The levels of second messengers are exquisitely controlled temporally and spatially, and, during signaling, enzymatic reactions or opening of ion channels ensure that they are highly amplified. These messengers then diffuse rapidly from the source and bind to target proteins to alter their properties (activity, localization, stability, etc.) to propagate signaling.
Topics: Lipid Metabolism; Nucleotides; Receptors, Cell Surface; Second Messenger Systems; Signal Transduction
PubMed: 27481708
DOI: 10.1101/cshperspect.a005926 -
Nature Chemical Biology Jan 2024O-linked β-N-acetyl glucosamine (O-GlcNAc) is at the crossroads of cellular metabolism, including glucose and glutamine; its dysregulation leads to molecular and...
O-linked β-N-acetyl glucosamine (O-GlcNAc) is at the crossroads of cellular metabolism, including glucose and glutamine; its dysregulation leads to molecular and pathological alterations that cause diseases. Here we report that O-GlcNAc directly regulates de novo nucleotide synthesis and nicotinamide adenine dinucleotide (NAD) production upon abnormal metabolic states. Phosphoribosyl pyrophosphate synthetase 1 (PRPS1), the key enzyme of the de novo nucleotide synthesis pathway, is O-GlcNAcylated by O-GlcNAc transferase (OGT), which triggers PRPS1 hexamer formation and relieves nucleotide product-mediated feedback inhibition, thereby boosting PRPS1 activity. PRPS1 O-GlcNAcylation blocked AMPK binding and inhibited AMPK-mediated PRPS1 phosphorylation. OGT still regulates PRPS1 activity in AMPK-deficient cells. Elevated PRPS1 O-GlcNAcylation promotes tumorigenesis and confers resistance to chemoradiotherapy in lung cancer. Furthermore, Arts-syndrome-associated PRPS1 R196W mutant exhibits decreased PRPS1 O-GlcNAcylation and activity. Together, our findings establish a direct connection among O-GlcNAc signals, de novo nucleotide synthesis and human diseases, including cancer and Arts syndrome.
Topics: Humans; AMP-Activated Protein Kinases; Phosphorylation; Protein Processing, Post-Translational; Glucose; Nucleotides; N-Acetylglucosaminyltransferases
PubMed: 37308732
DOI: 10.1038/s41589-023-01354-x -
Molecular Cell Sep 2021Metabolic networks support cancer cell survival, proliferation, and malignant progression. Cancer cells take up large amounts of nutrients such as glucose and glutamine...
Metabolic networks support cancer cell survival, proliferation, and malignant progression. Cancer cells take up large amounts of nutrients such as glucose and glutamine whose metabolism provides the energy, reducing equivalents, and biosynthetic precursors required to meet the biosynthetic demands of proliferation. Intermediates of glycolysis and the tricarboxylic acid (TCA) cycle provide critical building blocks for synthesis of non-essential amino acids, nucleotides, and fatty acids. To view this SnapShot, open or download the PDF.
Topics: Amino Acids; Citric Acid Cycle; Energy Metabolism; Glucose; Glutamine; Glycolysis; Humans; Metabolic Networks and Pathways; Neoplasms; Nucleotides
PubMed: 34547243
DOI: 10.1016/j.molcel.2021.06.021 -
Biomolecules Nov 2019Plastids, organelles that evolved from cyanobacteria via endosymbiosis in eukaryotes, provide carbohydrates for the formation of biomass and for mitochondrial energy... (Review)
Review
Plastids, organelles that evolved from cyanobacteria via endosymbiosis in eukaryotes, provide carbohydrates for the formation of biomass and for mitochondrial energy production to the cell. They generate their own energy in the form of the nucleotide adenosine triphosphate (ATP). However, plastids of non-photosynthetic tissues, or during the dark, depend on external supply of ATP. A dedicated antiporter that exchanges ATP against adenosine diphosphate (ADP) plus inorganic phosphate (Pi) takes over this function in most photosynthetic eukaryotes. Additional forms of such nucleotide transporters (NTTs), with deviating activities, are found in intracellular bacteria, and, surprisingly, also in diatoms, a group of algae that acquired their plastids from other eukaryotes via one (or even several) additional endosymbioses compared to algae with primary plastids and higher plants. In this review, we summarize what is known about the nucleotide synthesis and transport pathways in diatom cells, and discuss the evolutionary implications of the presence of the additional NTTs in diatoms, as well as their applications in biotechnology.
Topics: Biological Evolution; Biological Transport; Biotechnology; Diatoms; Membrane Transport Proteins; Nucleotides
PubMed: 31766535
DOI: 10.3390/biom9120761