1
|
Wang H, Stevens T, Lu J, Roberts A, Van't Land C, Muzumdar R, Gong Z, Vockley J, Prochownik EV. Body-Wide Inactivation of the Myc-Like Mlx Transcription Factor Network Accelerates Aging and Increases the Lifetime Cancer Incidence. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2401593. [PMID: 38976573 PMCID: PMC11425880 DOI: 10.1002/advs.202401593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 06/08/2024] [Indexed: 07/10/2024]
Abstract
The "Mlx" and "Myc" transcription factor networks cross-communicate and share many common gene targets. Myc's activity depends upon its heterodimerization with Max, whereas the Mlx Network requires that the Max-like factor Mlx associate with the Myc-like factors MondoA or ChREBP. The current work demonstrates that body-wide Mlx inactivation, like that of Myc, accelerates numerous aging-related phenotypes pertaining to body habitus and metabolism. The deregulation of numerous aging-related Myc target gene sets is also accelerated. Among other functions, these gene sets often regulate ribosomal and mitochondrial structure and function, genomic stability, and aging. Whereas "MycKO" mice have an extended lifespan because of a lower cancer incidence, "MlxKO" mice have normal lifespans and a higher cancer incidence. Like Myc, the expression of Mlx, MondoA, and ChREBP and their control over their target genes deteriorate with age in both mice and humans. Collectively, these findings underscore the importance of lifelong and balanced cross-talk between the two networks to maintain proper function and regulation of the many factors that can affect normal aging.
Collapse
Affiliation(s)
- Huabo Wang
- Division of Hematology/OncologyUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Taylor Stevens
- Division of Hematology/OncologyUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Jie Lu
- Division of Hematology/OncologyUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Alexander Roberts
- Division of Hematology/OncologyUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Clinton Van't Land
- Division of Medical GeneticsUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Radhika Muzumdar
- Division of EndocrinologyUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Zhenwei Gong
- Division of EndocrinologyUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Jerry Vockley
- Division of Medical GeneticsUPMC Children's Hospital of PittsburghPittsburghPA15201USA
| | - Edward V. Prochownik
- Division of Hematology/OncologyUPMC Children's Hospital of PittsburghPittsburghPA15201USA
- The Department of Microbiology and Molecular GeneticsUPMCPittsburghPA15201USA
- The Hillman Cancer Center of UPMC5115 Centre AvePittsburghPA15232USA
- The Pittsburgh Liver Research CenterUPMCPittsburghPA15224USA
| |
Collapse
|
2
|
Chambers TL, Dimet-Wiley A, Keeble AR, Haghani A, Lo WJ, Kang G, Brooke R, Horvath S, Fry CS, Watowich SJ, Wen Y, Murach KA. Methylome-proteome integration after late-life voluntary exercise training reveals regulation and target information for improved skeletal muscle health. J Physiol 2024. [PMID: 39058663 DOI: 10.1113/jp286681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/02/2024] [Indexed: 07/28/2024] Open
Abstract
Exercise is a potent stimulus for combatting skeletal muscle ageing. To study the effects of exercise on muscle in a preclinical setting, we developed a combined endurance-resistance training stimulus for mice called progressive weighted wheel running (PoWeR). PoWeR improves molecular, biochemical, cellular and functional characteristics of skeletal muscle and promotes aspects of partial epigenetic reprogramming when performed late in life (22-24 months of age). In this investigation, we leveraged pan-mammalian DNA methylome arrays and tandem mass-spectrometry proteomics in skeletal muscle to provide detailed information on late-life PoWeR adaptations in female mice relative to age-matched sedentary controls (n = 7-10 per group). Differential CpG methylation at conserved promoter sites was related to transcriptional regulation genes as well as Nr4a3, Hes1 and Hox genes after PoWeR. Using a holistic method of -omics integration called binding and expression target analysis (BETA), methylome changes were associated with upregulated proteins related to global and mitochondrial translation after PoWeR (P = 0.03). Specifically, BETA implicated methylation control of ribosomal, mitoribosomal, and mitochondrial complex I protein abundance after training. DNA methylation may also influence LACTB, MIB1 and UBR4 protein induction with exercise - all are mechanistically linked to muscle health. Computational cistrome analysis predicted several transcription factors including MYC as regulators of the exercise trained methylome-proteome landscape, corroborating prior late-life PoWeR transcriptome data. Correlating the proteome to muscle mass and fatigue resistance revealed positive relationships with VPS13A and NPL levels, respectively. Our findings expose differential epigenetic and proteomic adaptations associated with translational regulation after PoWeR that could influence skeletal muscle mass and function in aged mice. KEY POINTS: Late-life combined endurance-resistance exercise training from 22-24 months of age in mice is shown to improve molecular, biochemical, cellular and in vivo functional characteristics of skeletal muscle and promote aspects of partial epigenetic reprogramming and epigenetic age mitigation. Integration of DNA CpG 36k methylation arrays using conserved sites (which also contain methylation ageing clock sites) with exploratory proteomics in skeletal muscle extends our prior work and reveals coordinated and widespread regulation of ribosomal, translation initiation, mitochondrial ribosomal (mitoribosomal) and complex I proteins after combined voluntary exercise training in a sizeable cohort of female mice (n = 7-10 per group and analysis). Multi-omics integration predicted epigenetic regulation of serine β-lactamase-like protein (LACTB - linked to tumour resistance in muscle), mind bomb 1 (MIB1 - linked to satellite cell and type 2 fibre maintenance) and ubiquitin protein ligase E3 component N-recognin 4 (UBR4 - linked to muscle protein quality control) after training. Computational cistrome analysis identified MYC as a regulator of the late-life training proteome, in agreement with prior transcriptional analyses. Vacuolar protein sorting 13 homolog A (VPS13A) was positively correlated to muscle mass, and the glycoprotein/glycolipid associated sialylation enzyme N-acetylneuraminate pyruvate lyase (NPL) was associated to in vivo muscle fatigue resistance.
Collapse
Affiliation(s)
- Toby L Chambers
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
| | | | - Alexander R Keeble
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - Amin Haghani
- Department of Human Genetics, University of California Los Angeles, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
| | - Wen-Juo Lo
- Department of Educational Statistics and Research Methods, University of Arkansas, Fayetteville, AR, USA
| | - Gyumin Kang
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Physiology, University of Kentucky, Lexington, KY, USA
- Division of Biomedical Informatics, Department of Internal Medicine, University of Kentucky, Lexington, KY, USA
| | - Robert Brooke
- Epigenetic Clock Development Foundation, Los Angeles, CA, USA
| | - Steve Horvath
- Department of Human Genetics, University of California Los Angeles, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
- Epigenetic Clock Development Foundation, Los Angeles, CA, USA
| | - Christopher S Fry
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - Stanley J Watowich
- Ridgeline Therapeutics, Houston, TX, USA
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Yuan Wen
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Physiology, University of Kentucky, Lexington, KY, USA
- Division of Biomedical Informatics, Department of Internal Medicine, University of Kentucky, Lexington, KY, USA
| | - Kevin A Murach
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
| |
Collapse
|
3
|
Wang H, Ma B, Stevens T, Knapp J, Lu J, Prochownik EV. MYC Binding Near Transcriptional End Sites Regulates Basal Gene Expression, Read-Through Transcription and Intragenic Contacts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.11.603118. [PMID: 39071289 PMCID: PMC11275772 DOI: 10.1101/2024.07.11.603118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
The MYC oncoprotein regulates numerous genes involved in cellular processes such as cell cycle and mitochondrial and ribosomal structure and function. This requires heterodimerization with its partner, MAX, and binding to specific promoter and enhancer elements. Here, we show that MYC and MAX also bind near transcriptional end sites (TESs) of over one-sixth of all annotated genes. These interactions are dose-dependent, evolutionarily conserved, stabilize the normally short-lived MYC protein and regulate expression both in concert with and independent of MYC's binding elsewhere. MYC's TES binding occurs in association with other transcription factors, alters the chromatin landscape, increases nuclease susceptibility and can alter transcriptional read-through, particularly in response to certain stresses. MYC-bound TESs can directly contact promoters and may fine-tune gene expression in response to both physiologic and pathologic stimuli. Collectively, these findings support a previously unrecognized role for MYC in regulating transcription and its read-through via direct intragenic contacts between TESs and promoters.
Collapse
|
4
|
Jones RG, von Walden F, Murach KA. Exercise-Induced MYC as an Epigenetic Reprogramming Factor That Combats Skeletal Muscle Aging. Exerc Sport Sci Rev 2024; 52:63-67. [PMID: 38391187 PMCID: PMC10963142 DOI: 10.1249/jes.0000000000000333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Of the "Yamanaka factors" Oct3/4 , Sox2 , Klf4 , and c-Myc (OSKM), the transcription factor c-Myc ( Myc ) is the most responsive to exercise in skeletal muscle and is enriched within the muscle fiber. We hypothesize that the pulsatile induction of MYC protein after bouts of exercise can serve to epigenetically reprogram skeletal muscle toward a more resilient and functional state.
Collapse
Affiliation(s)
- Ronald G. Jones
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Ferdinand von Walden
- Neuropediatrics, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Kevin A. Murach
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
| |
Collapse
|
5
|
Lissek T. Aging as a Consequence of the Adaptation-Maladaptation Dilemma. Adv Biol (Weinh) 2024; 8:e2300654. [PMID: 38299389 DOI: 10.1002/adbi.202300654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/11/2024] [Indexed: 02/02/2024]
Abstract
In aging, the organism is unable to counteract certain harmful influences over its lifetime which leads to progressive dysfunction and eventually death, thus delineating aging as one failed process of adaptation to a set of aging stimuli. A central problem in understanding aging is hence to explain why the organism cannot adapt to these aging stimuli. The adaptation-maladaptation theory of aging proposes that in aging adaptation processes such as adaptive transcription, epigenetic remodeling, and metabolic plasticity drive dysfunction themselves over time (maladaptation) and thereby cause aging-related disorders such as cancer and metabolic dysregulation. The central dilemma of aging is thus that the set of adaptation mechanisms that the body uses to deal with internal and external stressors acts as a stressor itself and cannot be effectively counteracted. The only available option for the organism to decrease maladaptation may be a program to progressively reduce the output of adaptive cascades (e.g., via genomic methylation) which then leads to reduced physiological adaptation capacity and syndromes like frailty, immunosenescence, and cognitive decline. The adaptation-maladaptation dilemma of aging entails that certain biological mechanisms can simultaneously protect against aging as well as drive aging. The key to longevity may lie in uncoupling adaptation from maladaptation.
Collapse
Affiliation(s)
- Thomas Lissek
- Interdisciplinary Center for Neurosciences, Heidelberg University, Im Neuenheimer Feld 366, 69120, Heidelberg, Germany
| |
Collapse
|
6
|
Zacarías-Fluck MF, Soucek L, Whitfield JR. MYC: there is more to it than cancer. Front Cell Dev Biol 2024; 12:1342872. [PMID: 38510176 PMCID: PMC10952043 DOI: 10.3389/fcell.2024.1342872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/20/2024] [Indexed: 03/22/2024] Open
Abstract
MYC is a pleiotropic transcription factor involved in multiple cellular processes. While its mechanism of action and targets are not completely elucidated, it has a fundamental role in cellular proliferation, differentiation, metabolism, ribogenesis, and bone and vascular development. Over 4 decades of research and some 10,000 publications linking it to tumorigenesis (by searching PubMed for "MYC oncogene") have led to MYC becoming a most-wanted target for the treatment of cancer, where many of MYC's physiological functions become co-opted for tumour initiation and maintenance. In this context, an abundance of reviews describes strategies for potentially targeting MYC in the oncology field. However, its multiple roles in different aspects of cellular biology suggest that it may also play a role in many additional diseases, and other publications are indeed linking MYC to pathologies beyond cancer. Here, we review these physiological functions and the current literature linking MYC to non-oncological diseases. The intense efforts towards developing MYC inhibitors as a cancer therapy will potentially have huge implications for the treatment of other diseases. In addition, with a complementary approach, we discuss some diseases and conditions where MYC appears to play a protective role and hence its increased expression or activation could be therapeutic.
Collapse
Affiliation(s)
- Mariano F. Zacarías-Fluck
- Models of Cancer Therapies Laboratory, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
| | - Laura Soucek
- Models of Cancer Therapies Laboratory, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
- Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Bellaterra, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Peptomyc S.L., Barcelona, Spain
| | - Jonathan R. Whitfield
- Models of Cancer Therapies Laboratory, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain
| |
Collapse
|
7
|
Wang H, Stevens T, Lu J, Roberts A, Land CV, Muzumdar R, Gong Z, Vockley J, Prochownik EV. The Myc-Like Mlx Network Impacts Aging and Metabolism. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.26.568749. [PMID: 38076995 PMCID: PMC10705233 DOI: 10.1101/2023.11.26.568749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
The "Mlx" and "Myc" Networks share many common gene targets. Just as Myc's activity depends upon its heterodimerization with Max, the Mlx Network requires that the Max-like factor Mlx associate with the Myc-like factors MondoA or ChREBP. We show here that body-wide Mlx inactivation, like that of Myc, accelerates numerous aging-related phenotypes pertaining to body habitus and metabolism. The deregulation of numerous aging-related Myc target gene sets is also accelerated. Among other functions, these gene sets often regulate ribosomal and mitochondrial structure and function, genomic stability and aging. Whereas "MycKO" mice have an extended lifespan because of a lower cancer incidence, "MlxKO" mice have normal lifespans and a somewhat higher cancer incidence. Like Myc, Mlx, MondoA and ChREBP expression and that of their target genes, deteriorate with age in both mice and humans, underscoring the importance of life-long and balanced cross-talk between the two Networks to maintain normal aging.
Collapse
Affiliation(s)
- Huabo Wang
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh
| | - Taylor Stevens
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh
| | - Jie Lu
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh
| | - Alexander Roberts
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh
| | | | - Radhika Muzumdar
- Division of Endocrinology, UPMC Children’s Hospital of Pittsburgh
| | - Zhenwei Gong
- Division of Endocrinology, UPMC Children’s Hospital of Pittsburgh
| | - Jerry Vockley
- Division of Medical Genetics, UPMC Children’s Hospital of Pittsburgh
| | - Edward V. Prochownik
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh
- The Department of Microbiology and Molecular Genetics, UPMC
- The Hillman Cancer Center of UPMC
- The Pittsburgh Liver Research Center, UPMC, Pittsburgh, PA. 15224
| |
Collapse
|
8
|
Abstract
Perturbation of mitochondrial function can trigger a host of cellular responses that seek to restore cellular metabolism, cytosolic proteostasis, and redox homeostasis. In some cases, these responses persist even after the stress is relieved, leaving the cell or tissue in a less vulnerable state. This process-termed mitohormesis-is increasingly viewed as an important aspect of normal physiology and a critical modulator of various disease processes. Here, we review aspects of mitochondrial stress signaling that, among other things, can rewire the cell's metabolism, activate the integrated stress response, and alter cytosolic quality-control pathways. We also discuss how these pathways are implicated in various disease states from pathogen challenge to chemotherapeutic resistance and how their therapeutic manipulation can lead to new strategies for a host of chronic conditions including aging itself.
Collapse
Affiliation(s)
- Yu-Wei Cheng
- Aging Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jie Liu
- Aging Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Toren Finkel
- Aging Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| |
Collapse
|
9
|
Purhonen J, Klefström J, Kallijärvi J. MYC-an emerging player in mitochondrial diseases. Front Cell Dev Biol 2023; 11:1257651. [PMID: 37731815 PMCID: PMC10507175 DOI: 10.3389/fcell.2023.1257651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 08/21/2023] [Indexed: 09/22/2023] Open
Abstract
The mitochondrion is a major hub of cellular metabolism and involved directly or indirectly in almost all biological processes of the cell. In mitochondrial diseases, compromised respiratory electron transfer and oxidative phosphorylation (OXPHOS) lead to compensatory rewiring of metabolism with resemblance to the Warburg-like metabolic state of cancer cells. The transcription factor MYC (or c-MYC) is a major regulator of metabolic rewiring in cancer, stimulating glycolysis, nucleotide biosynthesis, and glutamine utilization, which are known or predicted to be affected also in mitochondrial diseases. Albeit not widely acknowledged thus far, several cell and mouse models of mitochondrial disease show upregulation of MYC and/or its typical transcriptional signatures. Moreover, gene expression and metabolite-level changes associated with mitochondrial integrated stress response (mt-ISR) show remarkable overlap with those of MYC overexpression. In addition to being a metabolic regulator, MYC promotes cellular proliferation and modifies the cell cycle kinetics and, especially at high expression levels, promotes replication stress and genomic instability, and sensitizes cells to apoptosis. Because cell proliferation requires energy and doubling of the cellular biomass, replicating cells should be particularly sensitive to defective OXPHOS. On the other hand, OXPHOS-defective replicating cells are predicted to be especially vulnerable to high levels of MYC as it facilitates evasion of metabolic checkpoints and accelerates cell cycle progression. Indeed, a few recent studies demonstrate cell cycle defects and nuclear DNA damage in OXPHOS deficiency. Here, we give an overview of key mitochondria-dependent metabolic pathways known to be regulated by MYC, review the current literature on MYC expression in mitochondrial diseases, and speculate how its upregulation may be triggered by OXPHOS deficiency and what implications this has for the pathogenesis of these diseases.
Collapse
Affiliation(s)
- Janne Purhonen
- Folkhälsan Research Center, Helsinki, Finland
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Juha Klefström
- Finnish Cancer Institute, FICAN South Helsinki University Hospital, Helsinki, Finland
- Translational Cancer Medicine, Medical Faculty, University of Helsinki, Helsinki, Finland
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA, United States
| | - Jukka Kallijärvi
- Folkhälsan Research Center, Helsinki, Finland
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| |
Collapse
|
10
|
Prochownik EV, Wang H. Lessons in aging from Myc knockout mouse models. Front Cell Dev Biol 2023; 11:1244321. [PMID: 37621775 PMCID: PMC10446843 DOI: 10.3389/fcell.2023.1244321] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 07/31/2023] [Indexed: 08/26/2023] Open
Abstract
Despite MYC being among the most intensively studied oncogenes, its role in normal development has not been determined as Myc-/- mice do not survival beyond mid-gestation. Myc ± mice live longer than their wild-type counterparts and are slower to accumulate many age-related phenotypes. However, Myc haplo-insufficiency likely conceals other important phenotypes as many high-affinity Myc targets genes continue to be regulated normally. By delaying Myc inactivation until after birth it has recently been possible to study the consequences of its near-complete total body loss and thus to infer its normal function. Against expectation, these "MycKO" mice lived significantly longer than control wild-type mice but manifested a marked premature aging phenotype. This seemingly paradoxical behavior was potentially explained by a >3-fold lower lifetime incidence of cancer, normally the most common cause of death in mice and often Myc-driven. Myc loss accelerated the accumulation of numerous "Aging Hallmarks", including the loss of mitochondrial and ribosomal structural and functional integrity, the generation of reactive oxygen species, the acquisition of genotoxic damage, the detrimental rewiring of metabolism and the onset of senescence. In both mice and humans, normal aging in many tissues was accompaniued by the downregulation of Myc and the loss of Myc target gene regulation. Unlike most mouse models of premature aging, which are based on monogenic disorders of DNA damage recognition and repair, the MycKO mouse model directly impacts most Aging Hallmarks and may therefore more faithfully replicate the normal aging process of both mice and humans. It further establishes that the strong association between aging and cancer can be genetically separated and is maintained by a single gene.
Collapse
Affiliation(s)
- Edward V. Prochownik
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA, United States
- The Department of Microbiology and Molecular Genetics, UPMC, Pittsburgh, PA, United States
- The Hillman Cancer Center of UPMC, Pittsburgh, PA, United States
- The Pittsburgh Liver Research Center, UPMC, Pittsburgh, PA, United States
| | - Huabo Wang
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA, United States
| |
Collapse
|