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Huang Y, Che X, Wang PW, Qu X. p53/MDM2 signaling pathway in aging, senescence and tumorigenesis. Semin Cancer Biol 2024; 101:44-57. [PMID: 38762096 DOI: 10.1016/j.semcancer.2024.05.001] [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: 04/16/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/20/2024]
Abstract
A wealth of evidence has emerged that there is an association between aging, senescence and tumorigenesis. Senescence, a biological process by which cells cease to divide and enter a status of permanent cell cycle arrest, contributes to aging and aging-related diseases, including cancer. Aging populations have the higher incidence of cancer due to a lifetime of exposure to cancer-causing agents, reduction of repairing DNA damage, accumulated genetic mutations, and decreased immune system efficiency. Cancer patients undergoing cytotoxic therapies, such as chemotherapy and radiotherapy, accelerate aging. There is growing evidence that p53/MDM2 (murine double minute 2) axis is critically involved in regulation of aging, senescence and oncogenesis. Therefore, in this review, we describe the functions and mechanisms of p53/MDM2-mediated senescence, aging and carcinogenesis. Moreover, we highlight the small molecular inhibitors, natural compounds and PROTACs (proteolysis targeting chimeras) that target p53/MDM2 pathway to influence aging and cancer. Modification of p53/MDM2 could be a potential strategy for treatment of aging, senescence and tumorigenesis.
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Affiliation(s)
- Youyi Huang
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China; Provincial key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China; Clinical Cancer Research Center of Shenyang, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China
| | - Xiaofang Che
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China; Provincial key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China; Clinical Cancer Research Center of Shenyang, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China
| | - Peter W Wang
- Department of Medicine, Oasis Medical Research Center, Watertown, MA 02472, USA.
| | - Xiujuan Qu
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China; Provincial key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China; Clinical Cancer Research Center of Shenyang, the First Hospital of China Medical University, Shenyang, Liaoning Province 110001, China.
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2
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Fuchs SNR, Stalmann USA, Snoeren IAM, Bindels E, Schmitz S, Banjanin B, Hoogenboezem RM, van Herk S, Saad M, Walter W, Haferlach T, Seillier L, Saez-Rodriguez J, Dugourd AJF, Lehmann KV, Ben-Neriah Y, Gleitz HFE, Schneider RK. Collaborative effect of Csnk1a1 haploinsufficiency and mutant p53 in Myc induction can promote leukemic transformation. Blood Adv 2024; 8:766-779. [PMID: 38147624 PMCID: PMC10847877 DOI: 10.1182/bloodadvances.2022008926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/21/2023] [Accepted: 12/09/2023] [Indexed: 12/28/2023] Open
Abstract
ABSTRACT It is still not fully understood how genetic haploinsufficiency in del(5q) myelodysplastic syndrome (MDS) contributes to malignant transformation of hematopoietic stem cells. We asked how compound haploinsufficiency for Csnk1a1 and Egr1 in the common deleted region on chromosome 5 affects hematopoietic stem cells. Additionally, Trp53 was disrupted as the most frequently comutated gene in del(5q) MDS using CRISPR/Cas9 editing in hematopoietic progenitors of wild-type (WT), Csnk1a1-/+, Egr1-/+, Csnk1a1/Egr1-/+ mice. A transplantable acute leukemia only developed in the Csnk1a1-/+Trp53-edited recipient. Isolated blasts were indefinitely cultured ex vivo and gave rise to leukemia after transplantation, providing a tool to study disease mechanisms or perform drug screenings. In a small-scale drug screening, the collaborative effect of Csnk1a1 haploinsufficiency and Trp53 sensitized blasts to the CSNK1 inhibitor A51 relative to WT or Csnk1a1 haploinsufficient cells. In vivo, A51 treatment significantly reduced blast counts in Csnk1a1 haploinsufficient/Trp53 acute leukemias and restored hematopoiesis in the bone marrow. Transcriptomics on blasts and their normal counterparts showed that the derived leukemia was driven by MAPK and Myc upregulation downstream of Csnk1a1 haploinsufficiency cooperating with a downregulated p53 axis. A collaborative effect of Csnk1a1 haploinsufficiency and p53 loss on MAPK and Myc upregulation was confirmed on the protein level. Downregulation of Myc protein expression correlated with efficient elimination of blasts in A51 treatment. The "Myc signature" closely resembled the transcriptional profile of patients with del(5q) MDS with TP53 mutation.
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Affiliation(s)
- Stijn N. R. Fuchs
- Department of Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
- Oncode Institute, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Ursula S. A. Stalmann
- Department of Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
- Oncode Institute, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Inge A. M. Snoeren
- Department of Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
- Oncode Institute, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Eric Bindels
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Stephani Schmitz
- Department of Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
- Oncode Institute, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Bella Banjanin
- Department of Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
- Oncode Institute, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Remco M. Hoogenboezem
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Stanley van Herk
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Mohamed Saad
- Department of Cell and Tumor Biology, Faculty of Medicine, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany
| | | | | | - Lancelot Seillier
- Cancer Research Center Cologne Essen, University Hospital Cologne, Cologne, Germany
- Joint Research Center for Computational Biomedicine, University Hospital Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany
| | - Julio Saez-Rodriguez
- Heidelberg University, Faculty of Medicine, and Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany
| | - Aurélien J. F. Dugourd
- Heidelberg University, Faculty of Medicine, and Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany
| | - Kjong-Van Lehmann
- Cancer Research Center Cologne Essen, University Hospital Cologne, Cologne, Germany
- Joint Research Center for Computational Biomedicine, University Hospital Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany
| | - Yinon Ben-Neriah
- The Lautenberg Center for Immunology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Hélène F. E. Gleitz
- Department of Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
- Oncode Institute, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Rebekka K. Schneider
- Department of Developmental Biology, Erasmus Medical Center, Rotterdam, the Netherlands
- Oncode Institute, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
- Department of Cell and Tumor Biology, Faculty of Medicine, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany
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3
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Chen J, Baxi K, Lipsitt AE, Hensch NR, Wang L, Sreenivas P, Modi P, Zhao XR, Baudin A, Robledo DG, Bandyopadhyay A, Sugalski A, Challa AK, Kurmashev D, Gilbert AR, Tomlinson GE, Houghton P, Chen Y, Hayes MN, Chen EY, Libich DS, Ignatius MS. Defining function of wild-type and three patient-specific TP53 mutations in a zebrafish model of embryonal rhabdomyosarcoma. eLife 2023; 12:e68221. [PMID: 37266578 PMCID: PMC10322150 DOI: 10.7554/elife.68221] [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] [Received: 03/09/2021] [Accepted: 06/01/2023] [Indexed: 06/03/2023] Open
Abstract
In embryonal rhabdomyosarcoma (ERMS) and generally in sarcomas, the role of wild-type and loss- or gain-of-function TP53 mutations remains largely undefined. Eliminating mutant or restoring wild-type p53 is challenging; nevertheless, understanding p53 variant effects on tumorigenesis remains central to realizing better treatment outcomes. In ERMS, >70% of patients retain wild-type TP53, yet mutations when present are associated with worse prognosis. Employing a kRASG12D-driven ERMS tumor model and tp53 null (tp53-/-) zebrafish, we define wild-type and patient-specific TP53 mutant effects on tumorigenesis. We demonstrate that tp53 is a major suppressor of tumorigenesis, where tp53 loss expands tumor initiation from <35% to >97% of animals. Characterizing three patient-specific alleles reveals that TP53C176F partially retains wild-type p53 apoptotic activity that can be exploited, whereas TP53P153Δ and TP53Y220C encode two structurally related proteins with gain-of-function effects that predispose to head musculature ERMS. TP53P153Δ unexpectedly also predisposes to hedgehog-expressing medulloblastomas in the kRASG12D-driven ERMS-model.
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Affiliation(s)
- Jiangfei Chen
- Institute of Environmental Safety and Human Health, Wenzhou Medical UniversityWenzhouChina
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
| | - Kunal Baxi
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Amanda E Lipsitt
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Pediatrics, Division of Hematology Oncology, UT Health Sciences CenterSan AntonioUnited States
| | - Nicole Rae Hensch
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Long Wang
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Prethish Sreenivas
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Paulomi Modi
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Xiang Ru Zhao
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Antoine Baudin
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Biochemistry and Structural Biology, UT Health Sciences CenterSan AntonioUnited States
| | - Daniel G Robledo
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
| | - Abhik Bandyopadhyay
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
| | - Aaron Sugalski
- Department of Pediatrics, Division of Hematology Oncology, UT Health Sciences CenterSan AntonioUnited States
| | - Anil K Challa
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Biology, University of Alabama at BirminghamBirminghamUnited States
| | - Dias Kurmashev
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
| | - Andrea R Gilbert
- Department of Pathology and Laboratory Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Gail E Tomlinson
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Pediatrics, Division of Hematology Oncology, UT Health Sciences CenterSan AntonioUnited States
| | - Peter Houghton
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
| | - Yidong Chen
- Department of Population Health Sciences, UT Health Sciences CenterSan AntonioUnited States
| | - Madeline N Hayes
- Developmental and Stem Cell Biology, Hospital for Sick ChildrenTorontoCanada
| | - Eleanor Y Chen
- Department of Laboratory Medicine and Pathology, University of WashingtonSeattleUnited States
| | - David S Libich
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Biochemistry and Structural Biology, UT Health Sciences CenterSan AntonioUnited States
| | - Myron S Ignatius
- Greehey Children's Cancer Research Institute (GCCRI), UT Health Sciences CenterSan AntonioUnited States
- Department of Molecular Medicine, UT Health Sciences CenterSan AntonioUnited States
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4
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Gul S, Akyel YK, Gul ZM, Isin S, Ozcan O, Korkmaz T, Selvi S, Danis I, Ipek OS, Aygenli F, Taskin AC, Akarlar BA, Ozlu N, Ozturk N, Ozturk N, Ünal DÖ, Guzel M, Turkay M, Okyar A, Kavakli IH. Discovery of a small molecule that selectively destabilizes Cryptochrome 1 and enhances life span in p53 knockout mice. Nat Commun 2022; 13:6742. [PMID: 36347873 PMCID: PMC9643396 DOI: 10.1038/s41467-022-34582-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Accepted: 10/31/2022] [Indexed: 11/09/2022] Open
Abstract
Cryptochromes are negative transcriptional regulators of the circadian clock in mammals. It is not clear how reducing the level of endogenous CRY1 in mammals will affect circadian rhythm and the relation of such a decrease with apoptosis. Here, we discovered a molecule (M47) that destabilizes Cryptochrome 1 (CRY1) both in vitro and in vivo. The M47 selectively enhanced the degradation rate of CRY1 by increasing its ubiquitination and resulted in increasing the circadian period length of U2OS Bmal1-dLuc cells. In addition, subcellular fractionation studies from mice liver indicated that M47 increased degradation of the CRY1 in the nucleus. Furthermore, M47-mediated CRY1 reduction enhanced oxaliplatin-induced apoptosis in Ras-transformed p53 null fibroblast cells. Systemic repetitive administration of M47 increased the median lifespan of p53-/- mice by ~25%. Collectively our data suggest that M47 is a promising molecule to treat forms of cancer depending on the p53 mutation.
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Affiliation(s)
- Seref Gul
- grid.15876.3d0000000106887552Department of Chemical and Biological Engineering, Koc University, 34450 Sariyer-Istanbul, Turkey ,grid.9601.e0000 0001 2166 6619Present Address: Department of Biology, Biotechnology Division, İstanbul University, TR-34116 Beyazit-Istanbul, Turkey
| | - Yasemin Kubra Akyel
- grid.9601.e0000 0001 2166 6619Faculty of Pharmacy, Department of Pharmacology, İstanbul University, TR-34116 Beyazit-Istanbul, Turkey ,grid.411781.a0000 0004 0471 9346Present Address: School of Medicine, Department of Medical Pharmacology, Istanbul Medipol University, Istanbul, Turkey
| | - Zeynep Melis Gul
- grid.15876.3d0000000106887552Department of Molecular Biology and Genetics, Koc University, İstanbul, Turkey
| | - Safak Isin
- grid.15876.3d0000000106887552Department of Molecular Biology and Genetics, Koc University, İstanbul, Turkey
| | - Onur Ozcan
- grid.15876.3d0000000106887552Department of Molecular Biology and Genetics, Koc University, İstanbul, Turkey
| | - Tuba Korkmaz
- grid.448834.70000 0004 0595 7127Department of Molecular Biology and Genetics, Gebze Technical University, Gebze, 41400 Kocaeli, Turkey
| | - Saba Selvi
- grid.448834.70000 0004 0595 7127Department of Molecular Biology and Genetics, Gebze Technical University, Gebze, 41400 Kocaeli, Turkey
| | - Ibrahim Danis
- grid.9601.e0000 0001 2166 6619Faculty of Pharmacy, Department of Analytical Chemistry, İstanbul University, TR-34116 Beyazit-Istanbul, Turkey ,grid.9601.e0000 0001 2166 6619İstanbul University Drug Research and Application Center (ILAM), TR-34116 Beyazıt-Istanbul, Turkey
| | - Ozgecan Savlug Ipek
- grid.411781.a0000 0004 0471 9346Regenerative and Restorative Medicine Research Center (REMER), İstanbul Medipol University, Kavacik Campus, Kavacik-Beykoz/Istanbul, 34810 Turkey ,grid.38575.3c0000 0001 2337 3561Department of Chemistry, Graduate School of Natural and Applied Sciences, Yildiz Technical University, Besiktas/Istanbul, 34349 Turkey
| | - Fatih Aygenli
- grid.448834.70000 0004 0595 7127Department of Molecular Biology and Genetics, Gebze Technical University, Gebze, 41400 Kocaeli, Turkey
| | - Ali Cihan Taskin
- grid.15876.3d0000000106887552Animal Research Facility, Research Center for Translational Medicine, Koc University, Rumelifeneri yolu, 34450 Sariyer-Istanbul, Turkey
| | - Büşra Aytül Akarlar
- grid.15876.3d0000000106887552Department of Molecular Biology and Genetics, Koc University, İstanbul, Turkey
| | - Nurhan Ozlu
- grid.15876.3d0000000106887552Department of Molecular Biology and Genetics, Koc University, İstanbul, Turkey
| | - Nuri Ozturk
- grid.448834.70000 0004 0595 7127Department of Molecular Biology and Genetics, Gebze Technical University, Gebze, 41400 Kocaeli, Turkey
| | - Narin Ozturk
- grid.9601.e0000 0001 2166 6619Faculty of Pharmacy, Department of Pharmacology, İstanbul University, TR-34116 Beyazit-Istanbul, Turkey
| | - Durişehvar Özer Ünal
- grid.9601.e0000 0001 2166 6619Faculty of Pharmacy, Department of Analytical Chemistry, İstanbul University, TR-34116 Beyazit-Istanbul, Turkey ,grid.9601.e0000 0001 2166 6619İstanbul University Drug Research and Application Center (ILAM), TR-34116 Beyazıt-Istanbul, Turkey
| | - Mustafa Guzel
- grid.411781.a0000 0004 0471 9346Regenerative and Restorative Medicine Research Center (REMER), İstanbul Medipol University, Kavacik Campus, Kavacik-Beykoz/Istanbul, 34810 Turkey ,grid.411781.a0000 0004 0471 9346International School of Medicine, Department of Medical Pharmacology, Kavacik Campus, İstanbul Medipol University, Kavacik-Beykoz/Istanbul, 34810 Turkey
| | - Metin Turkay
- grid.15876.3d0000000106887552Department of Industrial Engineering, Koc University, Istanbul, Turkey
| | - Alper Okyar
- grid.9601.e0000 0001 2166 6619Faculty of Pharmacy, Department of Pharmacology, İstanbul University, TR-34116 Beyazit-Istanbul, Turkey
| | - Ibrahim Halil Kavakli
- grid.15876.3d0000000106887552Department of Chemical and Biological Engineering, Koc University, 34450 Sariyer-Istanbul, Turkey ,grid.15876.3d0000000106887552Department of Molecular Biology and Genetics, Koc University, İstanbul, Turkey
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5
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Cavga AD, Tardu M, Korkmaz T, Keskin O, Ozturk N, Gursoy A, Kavakli IH. Cryptochrome deletion in p53 mutant mice enhances apoptotic and anti-tumorigenic responses to UV damage at the transcriptome level. Funct Integr Genomics 2019; 19:729-742. [DOI: 10.1007/s10142-019-00680-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 03/05/2019] [Accepted: 04/15/2019] [Indexed: 10/26/2022]
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6
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Manley W, Moreau MP, Azaro M, Siecinski SK, Davis G, Buyske S, Vieland V, Bassett AS, Brzustowicz L. Validation of a microRNA target site polymorphism in H3F3B that is potentially associated with a broad schizophrenia phenotype. PLoS One 2018. [PMID: 29529098 PMCID: PMC5847241 DOI: 10.1371/journal.pone.0194233] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Despite much progress, few genetic findings for schizophrenia have been assessed by functional validation experiments at the molecular level. We previously reported evidence for genetic linkage of broadly defined schizophrenia to chromosome 17q25 in a sample of 24 multiplex families. 2,002 SNPs under this linkage peak were analyzed for evidence of linkage disequilibrium using the posterior probability of linkage (PPL) framework. SNP rs1060120 produced the strongest evidence for association, with a PPLD|L score of 0.21. This SNP is located within the 3'UTR of the histone gene H3F3B and colocalizes with potential gene target miR-616. A custom miRNA target prediction program predicted that the binding of miR-616 to H3F3B transcripts would be altered by the allelic variants of rs1060120. We used dual luciferase assays to experimentally validate this interaction. The rs1060120 A allele significantly reduced luciferase expression, indicating a stronger interaction with miR-616 than the G allele (p = 0.000412). These results provide functional validation that this SNP could alter schizophrenia epigenetic mechanisms thereby contributing to schizophrenia-related disease risk.
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Affiliation(s)
- William Manley
- Department of Genetics, Rutgers University, Piscataway, NJ, United States of America
| | - Michael P. Moreau
- Department of Genetics, Rutgers University, Piscataway, NJ, United States of America
| | - Marco Azaro
- Department of Genetics, Rutgers University, Piscataway, NJ, United States of America
| | - Stephen K. Siecinski
- Department of Genetics, Rutgers University, Piscataway, NJ, United States of America
| | - Gillian Davis
- Department of Genetics, Rutgers University, Piscataway, NJ, United States of America
| | - Steven Buyske
- Department of Genetics, Rutgers University, Piscataway, NJ, United States of America
- Department of Statistics & Biostatistics, Rutgers University, Piscataway, NJ, United States of America
| | - Veronica Vieland
- Battelle Center for Mathematical Medicine, The Research Institute at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Anne S. Bassett
- Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Linda Brzustowicz
- Department of Genetics, Rutgers University, Piscataway, NJ, United States of America
- * E-mail:
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7
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Velcheti V, Radivoyevitch T, Saunthararajah Y. Higher-Level Pathway Objectives of Epigenetic Therapy: A Solution to the p53 Problem in Cancer. Am Soc Clin Oncol Educ Book 2017; 37:812-824. [PMID: 28561650 DOI: 10.1200/edbk_174175] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Searches for effective yet nontoxic oncotherapies are searches for exploitable differences between cancer and normal cells. In its core of cell division, cancer resembles normal life, coordinated by the master transcription factor MYC. Outside of this core, apoptosis and differentiation programs, which dominantly antagonize MYC to terminate cell division, necessarily differ between cancer and normal cells, as apoptosis is suppressed by biallelic inactivation of the master regulator of apoptosis, p53, or its cofactor p16/CDKN2A in approximately 80% of cancers. These genetic alterations impact therapy: conventional oncotherapy applies stress upstream of p53 to upregulate it and causes apoptosis (cytotoxicity)-a toxic, futile intent when it is absent or nonfunctional. Differentiation, on the other hand, cannot be completely suppressed because it is a continuum along which all cells exist. Neoplastic evolution stalls advances along this continuum at its most proliferative points-in lineage-committed progenitors that have division times measured in hours compared with weeks for tissue stem cells. This differentiation arrest is by mutations/deletions in differentiation-driving transcription factors or their coactivators that shift balances of gene-regulating protein complexes toward corepressors that repress instead of activate hundreds of terminal differentiation genes. That is, malignant proliferation without differentiation, also referred to as cancer "stem" cell self-renewal, hinges on druggable corepressors. Inhibiting these corepressors (e.g., DNMT1) releases p53-independent terminal differentiation in cancer stem cells but preserves self-renewal of normal stem cells that express stem cell transcription factors. Thus, epigenetic-differentiation therapies exploit a fundamental distinction between cancer and normal stem cell self-renewal and have a pathway of action downstream of genetic defects in cancer, affording favorable therapeutic indices needed for clinical progress.
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Affiliation(s)
- Vamsidhar Velcheti
- From the Department of Hematology & Medical Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH; Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH; Department of Translational Hematology & Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
| | - Tomas Radivoyevitch
- From the Department of Hematology & Medical Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH; Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH; Department of Translational Hematology & Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
| | - Yogen Saunthararajah
- From the Department of Hematology & Medical Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH; Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH; Department of Translational Hematology & Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
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8
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Mothersill C, Rusin A, Seymour C. Low doses and non-targeted effects in environmental radiation protection; where are we now and where should we go? ENVIRONMENTAL RESEARCH 2017; 159:484-490. [PMID: 28863303 DOI: 10.1016/j.envres.2017.08.029] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 08/12/2017] [Accepted: 08/14/2017] [Indexed: 06/07/2023]
Abstract
The field of low dose radiobiology has advanced considerably in the last 30 years from small indications in the 1980's that all was not simple, to a paradigm shift which occurred during the 1990's, which severely dented the dose-driven models and DNA centric theories which had dominated until then. However while the science has evolved, the application of that science in environmental health protection has not. A reason for this appears to be the uncertainties regarding the shape of the low dose response curve, which lead regulators to adopt a precautionary approach to radiation protection. Radiation protection models assume a linear relationship between dose (i.e. energy deposition) and effect (in this case probability of an adverse DNA interaction leading to a mutation). This model does not consider non-targeted effects (NTE) such as bystander effects or delayed effects, which occur in progeny cells or offspring not directly receiving energy deposition from the dose. There is huge controversy concerning the role of NTE with some saying they reflect "biology" and that repair and homeostatic mechanisms sort out the apparent damage while others consider them to be a class of damage which increases the size of the target. One thing which has recently become apparent is that NTE may be very critical for modelling long-term effects at the level of the population rather than the individual. The issue is that NTE resulting from an acute high dose such as occurred after the A-bomb or Chernobyl occur in parallel with chronic effects induced by the continuing residual effects due to radiation dose decay. This means that if ambient radiation doses are measured for example 25 years after the Chernobyl accident, they only represent a portion of the dose effect because the contribution of NTE is not included.
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Affiliation(s)
- Carmel Mothersill
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada.
| | - Andrej Rusin
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - Colin Seymour
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
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9
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Therapeutic targets in the selective killing of cancer cells by nanomaterials. Clin Chim Acta 2017; 469:53-62. [DOI: 10.1016/j.cca.2017.03.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/19/2017] [Accepted: 03/19/2017] [Indexed: 12/13/2022]
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10
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Onyido EK, Sweeney E, Nateri AS. Wnt-signalling pathways and microRNAs network in carcinogenesis: experimental and bioinformatics approaches. Mol Cancer 2016; 15:56. [PMID: 27590724 PMCID: PMC5010773 DOI: 10.1186/s12943-016-0541-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/26/2016] [Indexed: 02/02/2023] Open
Abstract
Over the past few years, microRNAs (miRNAs) have not only emerged as integral regulators of gene expression at the post-transcriptional level but also respond to signalling molecules to affect cell function(s). miRNAs crosstalk with a variety of the key cellular signalling networks such as Wnt, transforming growth factor-β and Notch, control stem cell activity in maintaining tissue homeostasis, while if dysregulated contributes to the initiation and progression of cancer. Herein, we overview the molecular mechanism(s) underlying the crosstalk between Wnt-signalling components (canonical and non-canonical) and miRNAs, as well as changes in the miRNA/Wnt-signalling components observed in the different forms of cancer. Furthermore, the fundamental understanding of miRNA-mediated regulation of Wnt-signalling pathway and vice versa has been significantly improved by high-throughput genomics and bioinformatics technologies. Whilst, these approaches have identified a number of specific miRNA(s) that function as oncogenes or tumour suppressors, additional analyses will be necessary to fully unravel the links among conserved cellular signalling pathways and miRNAs and their potential associated components in cancer, thereby creating therapeutic avenues against tumours. Hence, we also discuss the current challenges associated with Wnt-signalling/miRNAs complex and the analysis using the biomedical experimental and bioinformatics approaches.
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Affiliation(s)
- Emenike K Onyido
- Cancer Genetics & Stem Cell Group, Cancer Biology Unit, Division of Cancer & Stem Cells, School of Medicine, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Eloise Sweeney
- Cancer Genetics & Stem Cell Group, Cancer Biology Unit, Division of Cancer & Stem Cells, School of Medicine, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Abdolrahman Shams Nateri
- Cancer Genetics & Stem Cell Group, Cancer Biology Unit, Division of Cancer & Stem Cells, School of Medicine, University of Nottingham, Nottingham, NG7 2UH, UK.
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11
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Christy B, Demaria M, Campisi J, Huang J, Jones D, Dodds SG, Williams C, Hubbard G, Livi CB, Gao X, Weintraub S, Curiel T, Sharp ZD, Hasty P. p53 and rapamycin are additive. Oncotarget 2016; 6:15802-13. [PMID: 26158292 PMCID: PMC4599238 DOI: 10.18632/oncotarget.4602] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 06/14/2015] [Indexed: 12/13/2022] Open
Abstract
Mechanistic target of rapamycin (mTOR) is a kinase found in a complex (mTORC1) that enables macromolecular synthesis and cell growth and is implicated in cancer etiology. The rapamycin-FK506 binding protein 12 (FKBP12) complex allosterically inhibits mTORC1. In response to stress, p53 inhibits mTORC1 through a separate pathway involving cell signaling and amino acid sensing. Thus, these different mechanisms could be additive. Here we show that p53 improved the ability of rapamycin to: 1) extend mouse life span, 2) suppress ionizing radiation (IR)-induced senescence-associated secretory phenotype (SASP) and 3) increase the levels of amino acids and citric acid in mouse embryonic stem (ES) cells. This additive effect could have implications for cancer treatment since rapamycin and p53 are anti-oncogenic.
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Affiliation(s)
- Barbara Christy
- Departments of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Cancer Therapy & Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Marco Demaria
- Buck Institute for Research on Aging, Novato, CA, USA
| | | | - Jing Huang
- Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Diane Jones
- Departments of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Sherry G Dodds
- Departments of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Charnae Williams
- Departments of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Gene Hubbard
- Department of Pathology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Carolina B Livi
- Departments of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Current address: Agilent Technologies, Inc., Santa Clara, CA, USA
| | - Xiaoli Gao
- Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Susan Weintraub
- Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Tyler Curiel
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Cancer Therapy & Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Z Dave Sharp
- Departments of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Cancer Therapy & Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Paul Hasty
- Departments of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Cancer Therapy & Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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12
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Lennicke C, Rahn J, Lichtenfels R, Wessjohann LA, Seliger B. Hydrogen peroxide - production, fate and role in redox signaling of tumor cells. Cell Commun Signal 2015; 13:39. [PMID: 26369938 PMCID: PMC4570748 DOI: 10.1186/s12964-015-0118-6] [Citation(s) in RCA: 328] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 09/08/2015] [Indexed: 02/07/2023] Open
Abstract
Hydrogen peroxide (H2O2) is involved in various signal transduction pathways and cell fate decisions. The mechanism of the so called “redox signaling” includes the H2O2-mediated reversible oxidation of redox sensitive cysteine residues in enzymes and transcription factors thereby altering their activities. Depending on its intracellular concentration and localization, H2O2 exhibits either pro- or anti-apoptotic activities. In comparison to normal cells, cancer cells are characterized by an increased H2O2 production rate and an impaired redox balance thereby affecting the microenvironment as well as the anti-tumoral immune response. This article reviews the current knowledge about the intracellular production of H2O2 along with redox signaling pathways mediating either the growth or apoptosis of tumor cells. In addition it will be discussed how the targeting of H2O2-linked sources and/or signaling components involved in tumor progression and survival might lead to novel therapeutic targets.
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Affiliation(s)
- Claudia Lennicke
- Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Magdeburger Str. 2, 06112, Halle/Saale, Germany
| | - Jette Rahn
- Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Magdeburger Str. 2, 06112, Halle/Saale, Germany
| | - Rudolf Lichtenfels
- Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Magdeburger Str. 2, 06112, Halle/Saale, Germany
| | - Ludger A Wessjohann
- Leibniz-Institute of Plant Biochemistry, Weinberg 3, 06120, Halle /Saale, Germany
| | - Barbara Seliger
- Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Magdeburger Str. 2, 06112, Halle/Saale, Germany.
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13
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Glasauer A, Chandel NS. Targeting antioxidants for cancer therapy. Biochem Pharmacol 2014; 92:90-101. [DOI: 10.1016/j.bcp.2014.07.017] [Citation(s) in RCA: 259] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/16/2014] [Accepted: 07/17/2014] [Indexed: 02/07/2023]
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Abstract
p53 is a crucial tumour suppressor that responds to diverse stress signals by orchestrating specific cellular responses, including transient cell cycle arrest, cellular senescence and apoptosis, which are all processes associated with tumour suppression. However, recent studies have challenged the relative importance of these canonical cellular responses for p53-mediated tumour suppression and have highlighted roles for p53 in modulating other cellular processes, including metabolism, stem cell maintenance, invasion and metastasis, as well as communication within the tumour microenvironment. In this Opinion article, we discuss the roles of classical p53 functions, as well as emerging p53-regulated processes, in tumour suppression.
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Affiliation(s)
- Kathryn T Bieging
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, Stanford University School of Medicine, CCSR-South, Room 1255, 269 Campus Drive, Stanford, California 94305, USA
| | - Stephano Spano Mello
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, Stanford University School of Medicine, CCSR-South, Room 1255, 269 Campus Drive, Stanford, California 94305, USA
| | - Laura D Attardi
- 1] Division of Radiation and Cancer Biology, Department of Radiation Oncology, Stanford University School of Medicine, CCSR-South, Room 1255, 269 Campus Drive, Stanford, California 94305, USA. [2] Department of Genetics, Stanford University School of Medicine, CCSR-South, Room 1255, 269 Campus Drive, Stanford, California 94305, USA
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15
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Microarray analysis of serum mRNA in patients with head and neck squamous cell carcinoma at whole-genome scale. BIOMED RESEARCH INTERNATIONAL 2014; 2014:408683. [PMID: 24864240 PMCID: PMC4017838 DOI: 10.1155/2014/408683] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 02/24/2014] [Indexed: 12/18/2022]
Abstract
With the increasing demand for noninvasive approaches in monitoring head and neck cancer, circulating nucleic acids have been shown to be a promising tool. We focused on the global transcriptome of serum samples of head and neck squamous cell carcinoma (HNSCC) patients in comparison with healthy individuals. We compared gene expression patterns of 36 samples. Twenty-four participants including 16 HNSCC patients (from 12 patients we obtained blood samples 1 year posttreatment) and 8 control subjects were recruited. The Illumina HumanWG-6 v3 Expression BeadChip was used to profile and identify the differences in serum mRNA transcriptomes. We found 159 genes to be significantly changed (Storey's P value <0.05) between normal and cancer serum specimens regardless of factors including p53 and B-cell lymphoma family members (Bcl-2, Bcl-XL). In contrast, there was no difference in gene expression between samples obtained before and after surgery in cancer patients. We suggest that microarray analysis of serum cRNA in patients with HNSCC should be suitable for refinement of early stage diagnosis of disease that can be important for development of new personalized strategies in diagnosis and treatment of tumours but is not suitable for monitoring further development of disease.
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16
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Kido T, Schubert S, Hatakeyama S, Ohyama C, Schmidtke J, Lau YFC. Expression of a Y-located human proto-oncogene TSPY in a transgenic mouse model of prostate cancer. Cell Biosci 2014; 4:9. [PMID: 24528896 PMCID: PMC3942074 DOI: 10.1186/2045-3701-4-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 12/17/2013] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND The human TSPY is the putative gene for the gonadoblastoma locus on the Y chromosome (GBY). Various molecular, pathological and transgenic mouse studies suggest that TSPY is a Y-located proto-oncogene contributing to the initiation/progression in human cancers, including germ cell tumors and various somatic cancers, such as prostate and liver cancer, and melanoma. The TgTSPY9 transgenic mouse line harbors a 8.2-kb human TSPY structural gene, which is tandemly integrated in the mouse Y chromosome, and expressed in a similar pattern as that of the endogenous gene in the human genome. This mouse model of human TSPY gene offers an opportunity to examine its behavior and potential contribution in various mouse models of human diseases, such as human cancers. We had investigated the expression of such TSPY-transgene in the LADY mouse model of prostate cancer, harboring a SV40 T antigen gene directed by a rat probasin promoter; and compared the expression pattern with those of endogenous TSPY gene and biomarkers in human prostate cancer specimens. RESULTS By introducing the Y-located TSPY-transgene to the LADY mice, we had examined the expression pattern of the human TSPY during prostatic oncogenesis in this mouse model of prostate cancer. Our results showed that the TSPY-transgene was activated in selected areas of the hypercellular stroma but not in the intraepithelial cells/neoplasia in the prostates of TgTSPY9/LADY mice. Using a specific biomarker, FOXA1, for epithelial cells, we demonstrated that TSPY-positive cells proliferated exclusively in the cancerous stroma in the LADY model at late stages of tumorigenesis. In contrast, in the human situation, TSPY was predominantly co-expressed with FOXA1 in the epithelial cells of PIN lesions and FOXA1 and another cancer biomarker, AMACR, in the adenocarcinoma cells in clinical prostate cancer samples of various degrees of malignancy. CONCLUSIONS Our data show that human TSPY could be abnormally activated during prostatic oncogenesis, and could possibly contribute to the heterogeneity of prostate cancer. The differential expression patterns of the human TSPY between the LADY mouse model and clinical prostate cancer suggest potential limitations of current mouse models for studies of either TSPY behavior in diseased conditions or prostate cancer development.
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Affiliation(s)
| | | | | | | | | | - Yun-Fai Chris Lau
- Laboratory of Cell and Developmental Genetics, Department of Medicine, VA Medical Center & Institute for Human Genetics, University of California, 4150 Clement Street, San Francisco, CA, USA.
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17
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Garcia PB, Attardi LD. Illuminating p53 function in cancer with genetically engineered mouse models. Semin Cell Dev Biol 2014; 27:74-85. [PMID: 24394915 DOI: 10.1016/j.semcdb.2013.12.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 12/06/2013] [Accepted: 12/23/2013] [Indexed: 01/23/2023]
Abstract
The key role of the p53 protein in tumor suppression is highlighted by its frequent mutation in human cancers and by the completely penetrant cancer predisposition of p53 null mice. Beyond providing definitive evidence for the critical function of p53 in tumor suppression, genetically engineered mouse models have offered numerous additional insights into p53 function. p53 knock-in mice expressing tumor-derived p53 mutants have revealed that these mutants display gain-of-function activities that actively promote carcinogenesis. The generation of p53 knock-in mutants with alterations in different domains of p53 has helped further elucidate the cellular and biochemical activities of p53 that are most fundamental for tumor suppression. In addition, modulation of p53 post-translational modification (PTM) status by generating p53 knock-in mouse strains with mutations in p53 PTM sites has revealed a subtlety and complexity to p53 regulation. Analyses of mouse models perturbing upstream regulators of p53 have solidified the notion that the p53 pathway can be compromised by means other than direct p53 mutation. Finally, switchable p53 models that allow p53 reactivation in tumors have helped evaluate the potential of p53 restoration therapy for cancer treatment. Collectively, mouse models have greatly enhanced our understanding of physiological p53 function and will continue to provide new biological and clinical insights in future investigations.
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Affiliation(s)
- Patty B Garcia
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Laura D Attardi
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
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18
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Hager KM, Gu W. Understanding the non-canonical pathways involved in p53-mediated tumor suppression. Carcinogenesis 2013; 35:740-6. [PMID: 24381013 DOI: 10.1093/carcin/bgt487] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In the last three decades since the discovery of p53, it has become increasingly apparent that p53 plays a very important role in tumor suppression. Previously, it was thought that the tumor suppressive functions lied solely in the canonical p53-mediated apoptosis, cell cycle arrest and senescence. However, more recent research has shown that anti-oncogenic activity of p53 can still occur in the absence of these downstream functions. These results suggest that more non-canonical roles of p53 may have a much larger impact on other p53-regulated programs then initially anticipated. Recently, the non-canonical activities of p53 such as cell metabolism, autophagy and necrosis have been the subject of intense study. p53 affects many aspects of cellular metabolism including catabolism, anabolism and reactive oxygen species levels. p53 has a dual role in autophagy regulation. Initiation of autophagy occurs through direct transcription of pro-autophagy genes and inhibition transpires through a transcription-independent mechanism. The role of p53 in these cellular processes is quite complex and evidence suggests that p53 can play both a pro- and anti-oncogenic role in these non-conical pathways. Despite of more than 60,000 publications on p53 in the literature, the mechanisms for p53-mediated tumor suppression apparently needs to be further elucidated.
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Affiliation(s)
- Kayla M Hager
- Department of Pathology and Cell Biology, Institute for Cancer Genetics and
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19
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Conditional inactivation of p53 in mature B cells promotes generation of nongerminal center-derived B-cell lymphomas. Proc Natl Acad Sci U S A 2013; 110:2934-9. [PMID: 23382223 DOI: 10.1073/pnas.1222570110] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The p53 tumor suppressor exerts a central role in protecting cells from oncogenic transformation. Accordingly, the p53 gene is mutated in a large number of human cancers. In mice, germ-line inactivation of p53 confers strong predisposition to development of different types of malignancies, but the early onset of thymic lymphomas in the majority of the animals prevents detailed studies of tumorigenesis in other tissues. Here, we use the Cre/Lox approach to inactivate p53 in mature B cells in mice (referred to as "CP" B cells) and find that such p53 inactivation results in the routine development of IgM-positive CP peripheral B-cell lymphomas. The CP lymphomas generally appear to arise, even in mice subjected to immunization protocols to activate germinal center reaction, from naive B cells that had not undergone immunoglobulin (Ig) heavy chain gene class switching or somatic hypermutation. In contrast to thymic lymphomas that arise in p53-deficient mice, which generally lack clonal translocations, nearly all analyzed CP B-cell tumors carried clonal translocations. However, in contrast to spontaneous translocations in other mouse B-cell tumor models, CP B-cell tumor translocations were not recurrent and did not involve Ig loci. Therefore, CP tumors might provide models for human lymphomas lacking Ig translocations, such as splenic marginal zone B-cell lymphoma or Waldenstrom macroglobulinemia. Our studies indicate that deletion of p53 is sufficient to trigger transformation of mature B cells and support the notion that p53 deficiency may allow accumulation of oncogenic translocations in B cells.
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20
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Halaby MJ, Hakem A, Li L, El Ghamrasni S, Venkatesan S, Hande PM, Sanchez O, Hakem R. Synergistic interaction of Rnf8 and p53 in the protection against genomic instability and tumorigenesis. PLoS Genet 2013; 9:e1003259. [PMID: 23382699 PMCID: PMC3561120 DOI: 10.1371/journal.pgen.1003259] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 12/04/2012] [Indexed: 11/18/2022] Open
Abstract
Rnf8 is an E3 ubiquitin ligase that plays a key role in the DNA damage response as well as in the maintenance of telomeres and chromatin remodeling. Rnf8−/− mice exhibit developmental defects and increased susceptibility to tumorigenesis. We observed that levels of p53, a central regulator of the cellular response to DNA damage, increased in Rnf8−/− mice in a tissue- and cell type–specific manner. To investigate the role of the p53-pathway inactivation on the phenotype observed in Rnf8−/− mice, we have generated Rnf8−/−p53−/− mice. Double-knockout mice showed similar growth retardation defects and impaired class switch recombination compared to Rnf8−/− mice. In contrast, loss of p53 fully rescued the increased apoptosis and reduced number of thymocytes and splenocytes in Rnf8−/− mice. Similarly, the senescence phenotype of Rnf8−/− mouse embryonic fibroblasts was rescued in p53 null background. Rnf8−/−p53−/− cells displayed defective cell cycle checkpoints and DNA double-strand break repair. In addition, Rnf8−/−p53−/− mice had increased levels of genomic instability and a remarkably elevated tumor incidence compared to either Rnf8−/− or p53−/− mice. Altogether, the data in this study highlight the importance of p53-pathway activation upon loss of Rnf8, suggesting that Rnf8 and p53 functionally interact to protect against genomic instability and tumorigenesis. DNA double-strand breaks are the most dangerous type of DNA lesions that can occur in cells. Failure to repair these breaks quickly and efficiently can result in either cell death or genomic instability and eventually malignant transformation. Rnf8 and p53 are key proteins in the DNA damage response. We have generated mice that are deficient in both Rnf8 and p53 proteins to determine how these two proteins interact. We found that, when p53 is absent, some of the developmental defects caused by Rnf8 deficiency are rescued. However, this is at the expense of increased chromosomal abnormalities caused by the inability of double-mutant cells to restrain DNA synthesis and cell proliferation and by their escape of cell death in the presence of damaged DNA. We showed that loss of both Rnf8 and p53 led to the accelerated development of both hematological and solid tumors. This study has important implications for human cancer, where mutations in the p53 gene are found in more than 50% of all cancers but where the other factors that facilitate cancer development are not well understood. This study suggests cooperation between Rnf8 and p53 in the prevention of cancer.
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Affiliation(s)
- Marie-Jo Halaby
- Department of Medical Biophysics, University of Toronto and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Anne Hakem
- Department of Medical Biophysics, University of Toronto and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Li Li
- Department of Medical Biophysics, University of Toronto and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Samah El Ghamrasni
- Department of Medical Biophysics, University of Toronto and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Shriram Venkatesan
- Department of Physiology, Yong Loo Lin School of Medicine and Tembusu College, National University of Singapore, Singapore, Singapore
| | - Prakash M. Hande
- Department of Physiology, Yong Loo Lin School of Medicine and Tembusu College, National University of Singapore, Singapore, Singapore
| | - Otto Sanchez
- University of Ontario Institute of Technology, Oshawa, Ontario, Canada
| | - Razqallah Hakem
- Department of Medical Biophysics, University of Toronto and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
- * E-mail:
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Saunthararajah Y, Triozzi P, Rini B, Singh A, Radivoyevitch T, Sekeres M, Advani A, Tiu R, Reu F, Kalaycio M, Copelan E, Hsi E, Lichtin A, Bolwell B. p53-Independent, normal stem cell sparing epigenetic differentiation therapy for myeloid and other malignancies. Semin Oncol 2012; 39:97-108. [PMID: 22289496 PMCID: PMC3655437 DOI: 10.1053/j.seminoncol.2011.11.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cytotoxic chemotherapy for acute myeloid leukemia (AML) usually produces only temporary remissions, at the cost of significant toxicity and risk for death. One fundamental reason for treatment failure is that it is designed to activate apoptosis genes (eg, TP53) that may be unavailable because of mutation or deletion. Unlike deletion of apoptosis genes, genes that mediate cell cycle exit by differentiation are present in myelodysplastic syndrome (MDS) and AML cells but are epigenetically repressed: MDS/AML cells express high levels of key lineage-specifying transcription factors. Mutations in these transcription factors (eg, CEBPA) or their cofactors (eg., RUNX1) affect transactivation function and produce epigenetic repression of late-differentiation genes that antagonize MYC. Importantly, this aberrant epigenetic repression can be redressed clinically by depleting DNA methyltransferase 1 (DNMT1, a central component of the epigenetic network that mediates transcription repression) using the deoxycytidine analogue decitabine at non-cytotoxic concentrations. The DNMT1 depletion is sufficient to trigger upregulation of late-differentiation genes and irreversible cell cycle exit by p53-independent differentiation mechanisms. Fortuitously, the same treatment maintains or increases self-renewal of normal hematopoietic stem cells, which do not express high levels of lineage-specifying transcription factors. The biological rationale for this approach to therapy appears to apply to cancers other than MDS/AML also. Decitabine or 5-azacytidine dose and schedule can be rationalized to emphasize this mechanism of action, as an alternative or complement to conventional apoptosis-based oncotherapy.
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Affiliation(s)
- Yogen Saunthararajah
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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22
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Bieging KT, Attardi LD. Deconstructing p53 transcriptional networks in tumor suppression. Trends Cell Biol 2011; 22:97-106. [PMID: 22154076 DOI: 10.1016/j.tcb.2011.10.006] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 10/26/2011] [Accepted: 10/27/2011] [Indexed: 12/16/2022]
Abstract
p53 is a pivotal tumor suppressor that induces apoptosis, cell-cycle arrest and senescence in response to stress signals. Although p53 transcriptional activation is important for these responses, the mechanisms underlying tumor suppression have been elusive. To date, no single or compound mouse knockout of specific p53 target genes has recapitulated the dramatic tumor predisposition that characterizes p53-null mice. Recently, however, analysis of knock-in mice expressing p53 transactivation domain mutants has revealed a group of primarily novel direct p53 target genes that may mediate tumor suppression in vivo. We present here an overview of well-known p53 target genes and the tumor phenotypes of the cognate knockout mice, and address the recent identification of new p53 transcriptional targets and how they enhance our understanding of p53 transcriptional networks central for tumor suppression.
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Affiliation(s)
- Kathryn T Bieging
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
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23
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p53 independent epigenetic-differentiation treatment in xenotransplant models of acute myeloid leukemia. Leukemia 2011; 25:1739-50. [PMID: 21701495 DOI: 10.1038/leu.2011.159] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Suppression of apoptosis by TP53 mutation contributes to resistance of acute myeloid leukemia (AML) to conventional cytotoxic treatment. Using differentiation to induce irreversible cell cycle exit in AML cells could be a p53-independent treatment alternative, however, this possibility requires evaluation. In vitro and in vivo regimens of the deoxycytidine analogue decitabine that deplete the chromatin-modifying enzyme DNA methyl-transferase 1 without phosphorylating p53 or inducing early apoptosis were determined. These decitabine regimens but not equimolar DNA-damaging cytarabine upregulated the key late differentiation factors CCAAT enhancer-binding protein ɛ and p27/cyclin dependent kinase inhibitor 1B (CDKN1B), induced cellular differentiation and terminated AML cell cycle, even in cytarabine-resistant p53- and p16/CDKN2A-null AML cells. Leukemia initiation by xenotransplanted AML cells was abrogated but normal hematopoietic stem cell engraftment was preserved. In vivo, the low toxicity allowed frequent drug administration to increase exposure, an important consideration for S phase specific decitabine therapy. In xenotransplant models of p53-null and relapsed/refractory AML, the non-cytotoxic regimen significantly extended survival compared with conventional cytotoxic cytarabine. Modifying in vivo dose and schedule to emphasize this pathway of decitabine action can bypass a mechanism of resistance to standard therapy.
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24
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Naldi M, Pistolozzi M, Bertucci C, De Simone A, Altilia S, Pierini M, Franceschi C, Salvioli S, Andrisano V. Structural characterization of p53 isoforms due to the polymorphism at codon 72 by mass spectrometry and circular dichroism. J Pharm Biomed Anal 2010; 53:200-6. [DOI: 10.1016/j.jpba.2010.03.038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 03/25/2010] [Accepted: 03/26/2010] [Indexed: 01/06/2023]
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25
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Talos F, Moll UM. Role of the p53 family in stabilizing the genome and preventing polyploidization. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 676:73-91. [PMID: 20687470 DOI: 10.1007/978-1-4419-6199-0_5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Cellular defects resulting in chromosomal instability and aneuploidy are the most common features of human cancers. As a major tumor suppressor and intrinsic part of several cellular checkpoints, p53 contributes to maintenance of the stability of the genetic material, both in quality (ensures faithful replication) and quantity (preservation of diploidy). Although the exact trigger of p53 in case of numerical chromosomal aberrations is unknown, the absence of p53 allows polyploid cells to proliferate and generate unstable aneuploid progeny. A more recent addition to the p53 family, p73, emerged as an important contributor to genomic integrity when p53 is inactivated. p73 loss in p53-null background leads to a rapid increase in polyploidy and aneuploidy, markedly exceeding that caused by p53 loss alone. Constitutive deregulation of Cyclin-Cdk and p27/Kip1 activities and excess failure of the G2/M DNA damage checkpoint are important deficiencies associated with p73 loss.
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Affiliation(s)
- Flaminia Talos
- Department of Pathology, Health Science Center, State University of New York at Stony Brook, Stony Brook, New York 11794, USA
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26
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Walter MA, Hildebrandt IJ, Hacke K, Kesner AL, Kelly O, Lawson GW, Phelps ME, Czernin J, Weber WA, Schiestl RH. Small-animal PET/CT for monitoring the development and response to chemotherapy of thymic lymphoma in Trp53-/- mice. J Nucl Med 2010; 51:1285-92. [PMID: 20660381 DOI: 10.2967/jnumed.109.073585] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Transgenic mouse models of human cancers represent one of the most promising approaches to elucidate clinically relevant mechanisms of action and provide insights into the treatment efficacy of new antitumor drugs. The use of Trp53 transgenic mice (Trp53 knockout [Trp53(-/-)] mice) for these kinds of studies is, so far, restricted by limitations in detecting developing tumors and the lack of noninvasive tools for monitoring tumor growth, progression, and treatment response. METHODS We hypothesized that quantitative small-animal PET with (18)F-FDG was able to detect the onset and location of tumor development, follow tumor progression, and monitor response to chemotherapy. To test these hypotheses, C57BL/6J Trp53(-/-) mice underwent longitudinal small-animal PET during lymphoma development and gemcitabine treatment. Trp53 wild-type (Trp53(+/+)) mice were used as controls, and histology after full necropsy served as the gold standard. RESULTS In Trp53(+/+) mice, the thymic standardized uptake value (SUV) did not exceed 1.0 g/mL, with decreasing (18)F-FDG uptake over time. Conversely, all Trp53(-/-) mice that developed thymic lymphoma showed increasing thymic glucose metabolism, with a mean SUV doubling time of 9.0 wk (range, 6.0-17.5 wk). Using an SUV of 3.0 g/mL as a criterion provided a sensitivity of 78% and a specificity of 100% for the detection of thymic lymphoma. Treatment monitoring with (18)F-FDG PET correctly identified all histologic responses and relapses to gemcitabine. CONCLUSION (18)F-FDG small-animal PET can be used to visualize onset and progression of thymic lymphomas in Trp53(-/-) mice and monitor response to chemotherapy. Thus, (18)F-FDG small-animal PET provides an in vivo means to assess intervention studies in the Trp53 transgenic mouse model.
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Affiliation(s)
- Martin A Walter
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, Los Angeles, California, USA.
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Millau JF, Mai S, Bastien N, Drouin R. p53 functions and cell lines: have we learned the lessons from the past? Bioessays 2010; 32:392-400. [PMID: 20414897 DOI: 10.1002/bies.200900160] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
p53 has a determinant role in cancer prevention and is among the most studied proteins in the world. The majority of studies devoted to this protein are carried out in cell lines because they are easy to use and have naturally emerged as the main research tool in laboratories. However, the p53 pathway is commonly deregulated in cancer cells, from which the experimental cell lines are generally derived. The fact that the pathway is deregulated challenges the relevance of using cancer-derived cell lines to study wild-type p53 activities, or, in a broader sense, to study any normal cellular process. In the present article, we identify and discuss a number of limitations of cell lines using examples related to p53. Finally, we point out the general limitations of cell lines and propose solutions as alternatives to these cells.
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Affiliation(s)
- Jean-François Millau
- Division of Genetics, Department of Pediatrics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
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Kim IY, Shin JH, Seong JK. Mouse phenogenomics, toolbox for functional annotation of human genome. BMB Rep 2010; 43:79-90. [PMID: 20193125 DOI: 10.5483/bmbrep.2010.43.2.079] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mouse models are crucial for the functional annotation of human genome. Gene modification techniques including gene targeting and gene trap in mouse have provided powerful tools in the form of genetically engineered mice (GEM) for understanding the molecular pathogenesis of human diseases. Several international consortium and programs are under way to deliver mutations in every gene in mouse genome. The information from studying these GEM can be shared through international collaboration. However, there are many limitations in utility because not all human genes are knocked out in mouse and they are not yet phenotypically characterized by standardized ways which is required for sharing and evaluating data from GEM. The recent improvement in mouse genetics has now moved the bottleneck in mouse functional genomics from the production of GEM to the systematic mouse phenotype analysis of GEM. Enhanced, reproducible and comprehensive mouse phenotype analysis has thus emerged as a prerequisite for effectively engaging the phenotyping bottleneck. In this review, current information on systematic mouse phenotype analysis and an issue-oriented perspective will be provided.
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Affiliation(s)
- Il Yong Kim
- Laboratory of Developmental Biology and Genomics, BK21 Program for Veterinary Science, Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea
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Taneja P, Maglic D, Kai F, Zhu S, Kendig RD, Fry EA, Inoue K. Classical and Novel Prognostic Markers for Breast Cancer and their Clinical Significance. CLINICAL MEDICINE INSIGHTS-ONCOLOGY 2010; 4:15-34. [PMID: 20567632 PMCID: PMC2883240 DOI: 10.4137/cmo.s4773] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The use of biomarkers ensures breast cancer patients receive optimal treatment. Established biomarkers such as estrogen receptor (ER) and progesterone receptor (PR) have been playing significant roles in the selection and management of patients for endocrine therapy. HER2 is a strong predictor of response to trastuzumab. Recently, the roles of ER as a negative and HER2 as a positive indicator for chemotherapy have been established. Ki67 has traditionally been recognized as a poor prognostic factor, but recent studies suggest that measurement of Ki67-positive cells during treatment will more effectively predict treatment efficacy for both anti-hormonal and chemotherapy. p53 mutations are found in 20–35% of human breast cancers and are associated with aggressive disease with poor clinical outcome when the DNA-binding domain is mutated. The utility of cyclin D1 as a predictor of breast cancer prognosis is controversial, but cyclin D1b overexpression is associated with poor prognosis. Likewise, overexpression of the low molecular weight form of cyclin E1 protein predicts poor prognosis. Breast cancers from BRCA1/2 carriers often show high nuclear grades, negativity to ER/PR/HER2, and p53 mutations, and thus, are associated with poor prognosis. The prognostic values of other molecular markers, such as p14ARF, TBX2/3, VEGF in breast cancer are also discussed. Careful evaluation of these biomarkers with current treatment modality is required to determine whether their measurement or monitoring offer significant clinical benefits.
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Abstract
Mouse models of human cancer have played a vital role in understanding tumorigenesis and answering experimental questions that other systems cannot address. Advances continue to be made that allow better understanding of the mechanisms of tumor development, and therefore the identification of better therapeutic and diagnostic strategies. We review major advances that have been made in modeling cancer in the mouse and specific areas of research that have been explored with mouse models. For example, although there are differences between mice and humans, new models are able to more accurately model sporadic human cancers by specifically controlling timing and location of mutations, even within single cells. As hypotheses are developed in human and cell culture systems, engineered mice provide the most tractable and accurate test of their validity in vivo. For example, largely through the use of these models, the microenvironment has been established to play a critical role in tumorigenesis, since tumor development and the interaction with surrounding stroma can be studied as both evolve. These mouse models have specifically fueled our understanding of cancer initiation, immune system roles, tumor angiogenesis, invasion, and metastasis, and the relevance of molecular diversity observed among human cancers. Currently, these models are being designed to facilitate in vivo imaging to track both primary and metastatic tumor development from much earlier stages than previously possible. Finally, the approaches developed in this field to achieve basic understanding are emerging as effective tools to guide much needed development of treatment strategies, diagnostic strategies, and patient stratification strategies in clinical research.
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Affiliation(s)
- Jessica C Walrath
- Mouse Cancer Genetics Program, National Cancer Institute, Frederick, Maryland, USA
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Salvioli S, Capri M, Bucci L, Lanni C, Racchi M, Uberti D, Memo M, Mari D, Govoni S, Franceschi C. Why do centenarians escape or postpone cancer? The role of IGF-1, inflammation and p53. Cancer Immunol Immunother 2009; 58:1909-17. [PMID: 19139887 PMCID: PMC11030834 DOI: 10.1007/s00262-008-0639-6] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Accepted: 12/02/2008] [Indexed: 11/30/2022]
Abstract
BACKGROUND Centenarians are exceptionally long living individuals who escaped the most common age-related diseases. In particular they appear to be effectively protected from cancers. The mechanisms that underlie this protection are quite complex and still largely unclear. AIM To critically analyse the literature in order to propose a unifying hypothesis that can account for this cancer protection in centenarians. METHODS Review of the scientific literature regarding three main players in tumourigenesis such as IGF-1, inflammation and p53, and centenarians. RESULTS Centenarians appear to be characterised by low IGF-1-mediated responses and high levels of anti-inflammatory cytokines such as IL-10 and TGF-beta, a condition that results in protection from cancer. Both inflammation and IGF-1 pathway converge on the tumour suppressor p53. Accordingly, some studies indicate that genetic variants of p53 are associated with human longevity by providing protection from cancer mortality. CONCLUSIONS The available data let us to hypothesise that among other possible mechanisms, well-preserved p53-mediated responses are likely a key factor contributing to protection from cancer in centenarians.
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Affiliation(s)
- Stefano Salvioli
- Department of Experimental Pathology, University of Bologna, Bologna, Italy.
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32
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Targeted deletion of p73 in mice reveals its role in T cell development and lymphomagenesis. PLoS One 2009; 4:e7784. [PMID: 19907659 PMCID: PMC2771421 DOI: 10.1371/journal.pone.0007784] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Accepted: 10/13/2009] [Indexed: 11/25/2022] Open
Abstract
Transcriptional silencing of the p73 gene through methylation has been demonstrated in human leukemias and lymphomas. However, the role of p73 in the malignant process remains to be explored. We show here that p73 acts as a T cell-specific tumor suppressor in a genetically defined mouse model, and that concomitant ablation of p53 and p73 predisposes mice to an increased incidence of thymic lymphomas compared to the loss of p53 alone. Our results demonstrate a causal role for loss of p73 in progression of T cell lymphomas to the stage of aggressive, disseminated disease. We provide evidence that tumorigenesis in mice lacking p53 and p73 proceeds through mechanisms involving altered patterns of gene expression, defects in early T cell development, impaired apoptosis, and the ensuing accumulation of chromosomal aberrations. Collectively, our data imply that tumor suppressive properties of p73 are highly dependent on cellular context, wherein p73 plays a major role in T cell development and neoplasia.
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Abstract
Cell and molecular biological studies of p53 functions over the past 30 years have been complemented in the past 20 years by studies that use genetically engineered mice. As expected, mice that have mutant Trp53 alleles usually develop cancers of various types more rapidly than their counterparts that have wild-type Trp53 genes. These mouse studies have been instrumental in providing important new insights into p53 tumour suppressor function. Such studies have been facilitated by the development of increasingly sophisticated genetic engineering approaches, which allow the more precise manipulation of p53 structure and function in a mammalian model.
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Affiliation(s)
- Lawrence A Donehower
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA.
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34
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Hinkal G, Parikh N, Donehower LA. Timed somatic deletion of p53 in mice reveals age-associated differences in tumor progression. PLoS One 2009; 4:e6654. [PMID: 19680549 PMCID: PMC2721630 DOI: 10.1371/journal.pone.0006654] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Accepted: 07/13/2009] [Indexed: 12/21/2022] Open
Abstract
Inactivating mutations in the p53 tumor suppressor gene occur often in the progression of human cancers. p53 inhibits the outgrowth of nascent cancer cells through anti-proliferative actions (including induction of apoptosis or senescence). To test p53 tumor suppressor functions in a novel experimental context, we somatically deleted both p53 alleles in multiple tissues of mice at various ages. Mice homozygously deleted for p53 at 3 months of age showed a longer tumor latency compared to mice deleted for p53 at 6 and 12 months of age. These results are consistent with a model in which tissues accumulate oncogenically activated cells with age and these are held in check by wildtype p53. We also deleted p53 before, concurrent with, and after treatment of mice with ionizing radiation (IR). The absence or presence of p53 during IR treatment had no effect on radiation-induced lymphoma latency, confirming that the immediate p53 damage response was irrelevant for cancer prevention. Even the presence of wildtype p53 for up to four weeks post-IR provided no protection against early lymphoma incidence, indicating that long term maintenance of functional p53 is critical for preventing the emergence of a cancer. These experiments indicate that sustained p53 anti-oncogenic function acts as a final or near final line of defense preventing progression of oncogenically activated cells to malignant tumors.
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Affiliation(s)
- George Hinkal
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- Interdepartmental Program of Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Neha Parikh
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Lawrence A. Donehower
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- Interdepartmental Program of Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
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35
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Targeting cancer cells by ROS-mediated mechanisms: a radical therapeutic approach? Nat Rev Drug Discov 2009; 8:579-91. [PMID: 19478820 DOI: 10.1038/nrd2803] [Citation(s) in RCA: 3934] [Impact Index Per Article: 262.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Increased generation of reactive oxygen species (ROS) and an altered redox status have long been observed in cancer cells, and recent studies suggest that this biochemical property of cancer cells can be exploited for therapeutic benefits. Cancer cells in advanced stage tumours frequently exhibit multiple genetic alterations and high oxidative stress, suggesting that it might be possible to preferentially eliminate these cells by pharmacological ROS insults. However, the upregulation of antioxidant capacity in adaptation to intrinsic oxidative stress in cancer cells can confer drug resistance. Abrogation of such drug-resistant mechanisms by redox modulation could have significant therapeutic implications. We argue that modulating the unique redox regulatory mechanisms of cancer cells might be an effective strategy to eliminate these cells.
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36
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Cullen JM, Brown DL, Kissling GE, Foley JF, Rizzo J, Marion PL, Parron VI, French JE. Aflatoxin B1 and/or hepatitis B virus induced tumor spectrum in a genetically engineered hepatitis B virus expression and Trp53 haploinsufficient mouse model system for hepatocarcinogenesis. Toxicol Pathol 2009; 37:333-42. [PMID: 19258306 DOI: 10.1177/0192623309333137] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The authors investigated the spectrum of tumors and Trp53 mutations in genetically engineered models using the FVB/N mouse that expressed the hepatitis B virus genome and/or carried a Trp53 null and wildtype allele and/or were exposed to aflatoxin B1. Liver tumor incidence was increased when all three risk factors were present. Without aflatoxin B1 exposure, neither Trp53 haploinsufficiency nor HBV expression affected liver tumor development. Liver tumor prevalence increased with aflatoxin B1 exposure (p < .001), as thirteen of fourteen mice with liver tumors were initiated with aflatoxin B1. Liver tumors were more frequent in males (12/190) than females (2/170). Seventy-three mice developed sarcomas. Trp53 haploinsufficiency was associated with increased sarcoma incidence in males and females (p < .001). In Trp53 haploinsufficient mice, the HBV transgene increased the risk of sarcoma in males and females (p < .001). Lymphoma was significantly increased in Trp53 haploinsufficient FVB/N mice. There was no loss of heterozygosity at the wildtype Trp53 locus in twenty-five sarcomas or four hepatocellular tumors examined. No mutations were identified in the mRNA (exons 2-11) of Trp53 in six liver neoplasms or twenty-four sarcomas. In this model system, HBV expression affected only hepatocellular neoplasia in association with both aflatoxin B1 initiation and p53 haploinsufficiency.
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Affiliation(s)
- John M Cullen
- College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina 27606, USA.
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37
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Abstract
It is commonly thought that disruption of the circadian clock increases the cancer incidence in humans and mice. However, it was found that disruption of the clock by the Cryptochrome (Cry) mutation in mice did not increase cancer rate in the mutant mice even after exposing the animals to ionizing radiation. Therefore, in this study we tested the effect of the Cry mutation on carcinogenesis in a mouse strain prone to cancer because of a p53 mutation, with the expectation that clock disruption in this sensitized background would further increase cancer risk. Paradoxically, we find that the Cry mutation protects p53 mutant mice from the early onset of cancer and extends their median lifespan approximately 50%, in part by sensitizing p53 mutant cells to apoptosis in response to genotoxic stress. These results suggest alternative therapeutic approaches in management of cancers associated with a p53 mutation.
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Trachootham D, Lu W, Ogasawara MA, Valle NRD, Huang P. Redox regulation of cell survival. Antioxid Redox Signal 2008; 10:1343-74. [PMID: 18522489 PMCID: PMC2932530 DOI: 10.1089/ars.2007.1957] [Citation(s) in RCA: 1231] [Impact Index Per Article: 76.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 02/06/2008] [Accepted: 02/06/2008] [Indexed: 12/18/2022]
Abstract
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) play important roles in regulation of cell survival. In general, moderate levels of ROS/RNS may function as signals to promote cell proliferation and survival, whereas severe increase of ROS/RNS can induce cell death. Under physiologic conditions, the balance between generation and elimination of ROS/RNS maintains the proper function of redox-sensitive signaling proteins. Normally, the redox homeostasis ensures that the cells respond properly to endogenous and exogenous stimuli. However, when the redox homeostasis is disturbed, oxidative stress may lead to aberrant cell death and contribute to disease development. This review focuses on the roles of key transcription factors, signal-transduction pathways, and cell-death regulators in affecting cell survival, and how the redox systems regulate the functions of these molecules. The current understanding of how disturbance in redox homeostasis may affect cell death and contribute to the development of diseases such as cancer and degenerative disorders is reviewed. We also discuss how the basic knowledge on redox regulation of cell survival can be used to develop strategies for the treatment or prevention of those diseases.
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Affiliation(s)
- Dunyaporn Trachootham
- Department of Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas
- Faculty of Dentistry, Thammasat University (Rangsit Campus), Pathum-thani, Thailand
| | - Weiqin Lu
- Department of Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas
| | - Marcia A. Ogasawara
- Department of Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas
| | - Nilsa Rivera-Del Valle
- Department of Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas
| | - Peng Huang
- Department of Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas
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Palacios G, Talos F, Nemajerova A, Moll UM, Petrenko O. E2F1 plays a direct role in Rb stabilization and p53-independent tumor suppression. Cell Cycle 2008; 7:1776-81. [PMID: 18583939 DOI: 10.4161/cc.7.12.6030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
To better understand the role of E2F1 in tumor formation, we analyzed spontaneous tumorigenesis in p53(-/-)E2F1(+/+) and p53(-/-)E2F1(-/-) mice. We show that the combined loss of p53 and E2F1 leads to an increased incidence of sarcomas and carcinomas compared to the loss of p53 alone. E2F1-deficient tumors show wide chromosomal variation, indicative of genomic instability. Consistent with this, p53(-/-)E2F1(-/-) primary fibroblasts have a reduced capacity to maintain genomic stability when exposed to S-phase inhibitors or genotoxic drugs. A major mechanism of E2F1's contribution to genomic integrity lies in mediating stabilization and engagement of the Rb protein.
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Affiliation(s)
- Gustavo Palacios
- Department of Pathology, State University of New York at Stony Brook, Stony Brook, New York 11794, USA
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40
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Mutant alleles of HD improve the life span of p53(-/-) mice. Mech Ageing Dev 2008; 129:238-41. [PMID: 18242663 DOI: 10.1016/j.mad.2007.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Revised: 12/03/2007] [Accepted: 12/04/2007] [Indexed: 11/20/2022]
Abstract
Loss of function mutations in the p53 tumor suppressor gene predispose mice and humans to cancer, resulting in abbreviated life spans. A dominant mutation in the murine HD gene, similar to mutations that cause Huntington's disease in humans, reverses some of the effects of p53 mutations on longevity. We attribute this to the enhanced apoptotic effect of the expanded polyglutamine region in the HD protein on proliferating cells lacking p53.
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Abstract
Intense effort has been directed at understanding pathways modulating ageing in invertebrate model organisms. Prior to this decade, several longevity genes had been identified in flies, worms and yeast. More recently, with the development of RNAi libraries in worms and the yeast open reading frame (ORF) deletion collection, it has become routine to perform genome-wide screens for phenotypes of interest. A number of worm screens have now been performed to identify genes whose reduced expression leads to longer lifespan, and two ORF deletion longevity screens have been performed in yeast. Interestingly, these screens have linked previously unidentified cellular pathways to invertebrate ageing. More surprising, however, is the sheer number of longevity genes in worms and yeast. In this review, I discuss data from genome-wide screens in the context of evolutionary theories of ageing and raise issues regarding the increasing complexity associated with the genetics of longevity.
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Affiliation(s)
- B K Kennedy
- Department of Biochemistry, University of Washington, Seattle, WA, USA.
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Heinlein C, Krepulat F, Löhler J, Speidel D, Deppert W, Tolstonog GV. Mutant p53R270H gain of function phenotype in a mouse model for oncogene-induced mammary carcinogenesis. Int J Cancer 2007; 122:1701-9. [DOI: 10.1002/ijc.23317] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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43
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Runx2 deficiency and defective subnuclear targeting bypass senescence to promote immortalization and tumorigenic potential. Proc Natl Acad Sci U S A 2007; 104:19861-6. [PMID: 18077419 DOI: 10.1073/pnas.0709650104] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The osteogenic Runt-related (Runx2) transcription factor negatively regulates proliferation and ribosomal gene expression in normal diploid osteoblasts, but is up-regulated in metastatic breast and prostate cancer cells. Thus, Runx2 may function as a tumor suppressor or an oncogene depending on the cellular context. Here we show that Runx2-deficient primary osteoblasts fail to undergo senescence as indicated by the absence of beta-gal activity and p16(INK4a) tumor suppressor expression. Primary Runx2-null osteoblasts have a growth advantage and exhibit loss of p21(WAF1/CIP1) and p19(ARF) expression. Reintroduction of WT Runx2, but not a subnuclear targeting-defective mutant, induces both p21(WAF/CIP1) and p19(ARF) mRNA and protein resulting in cell-cycle inhibition. Accumulation of spontaneous phospho-H2A.X foci, loss of telomere integrity and the Mre11/Rad50/Nbs1 DNA repair complex, and a delayed DNA repair response all indicate that Runx2 deficiency leads to genomic instability. We propose that Runx2 functions as a tumor suppressor in primary diploid osteoblasts and that subnuclear targeting contributes to Runx2-mediated tumor suppression.
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The proline-rich domain in p63 is necessary for the transcriptional and apoptosis-inducing activities of TAp63. Oncogene 2007; 27:2843-50. [PMID: 18037962 DOI: 10.1038/sj.onc.1210948] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
p63 shares considerable sequence identity with p53, especially in its DNA-binding, activation and tetramerization domains. When the upstream promoter is used for p63 expression, three major transactivation p63 (TAp63) isoforms (alpha, beta and gamma) are produced. p63 is also expressed from an alternate promoter located in intron 3, producing three major DeltaNp63 isoforms. Recent studies demonstrated that p63 has the potential to function as a tumor suppressor or an oncoprotein. To further address this, we generated cell lines that inducibly express each TAp63 isoform. We showed that TAp63 isoforms are capable of inducing p53-responsive genes, inhibiting cell proliferation and promoting apoptosis. Interestingly, we discovered that both the activation domain (residues 1-59) and the proline-rich domain (residues 67-127) are required for TAp63 transcriptional activity. Likewise, TAp63beta(DeltaPRD), deleted of residues 60-133, possessed a greatly attenuated ability to induce endogenous target genes and promote apoptosis, but retained the ability to inhibit cell proliferation when expressed in stable, inducible cell lines. TAp63beta(DeltaPRD) also functioned as a dominant negative to wild-type p63beta in a dose-dependent manner. Furthermore, the loss of function seen with deletion of the proline-rich domain was not due to a DNA-binding defect, as TAp63beta(DeltaPRD) was found to strongly bind endogenous promoters using chromatin immunoprecipitation assay. Finally, mutational analysis revealed that a PXXP motif at residues 124-127 contributes to the transcriptional activity of TAp63. Altogether, our findings suggest that TAp63 transcriptional activity can be regulated by modification(s) of, or protein interactions with, the p63 proline-rich domain.
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Olsson A, Manzl C, Strasser A, Villunger A. How important are post-translational modifications in p53 for selectivity in target-gene transcription and tumour suppression? Cell Death Differ 2007; 14:1561-75. [PMID: 17627286 DOI: 10.1038/sj.cdd.4402196] [Citation(s) in RCA: 150] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
A number of elegant studies exploring the consequences of expression of various mutant forms of p53 in mice have been published over the last years. The results and conclusions drawn from these studies often contradict results previously obtained in biochemical assays and cell biology studies, questioning their relevance for p53 function in vivo. Owing to the multitude of post-translational modifications imposed on p53, however, the in vivo validation of their relevance for proper protein function and tumour suppression is constantly lagging behind new biochemical discoveries. Nevertheless, mouse genetics presents again its enormous power. Despite being relatively slow and tedious, it has become indispensable for researchers to sort out the wheat from the chaff in an endless sea of publications on p53.
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Affiliation(s)
- A Olsson
- Division of Developmental Immunology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
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Wijnhoven SWP, Speksnijder EN, Liu X, Zwart E, vanOostrom CTM, Beems RB, Hoogervorst EM, Schaap MM, Attardi LD, Jacks T, van Steeg H, Jonkers J, de Vries A. Dominant-negative but not gain-of-function effects of a p53.R270H mutation in mouse epithelium tissue after DNA damage. Cancer Res 2007; 67:4648-56. [PMID: 17510390 DOI: 10.1158/0008-5472.can-06-4681] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
p53 alterations in human tumors often involve missense mutations that may confer dominant-negative or gain-of-function properties. Dominant-negative effects result in inactivation of wild-type p53 protein in heterozygous mutant cells and as such in a p53 null phenotype. Gain-of-function effects can directly promote tumor development or metastasis through antiapoptotic mechanisms or transcriptional activation of (onco)genes. Here, we show, using conditional mouse technology, that epithelium-specific heterozygous expression of mutant p53 (i.e., the p53.R270H mutation that is equivalent to the human hotspot R273H) results in an increased incidence of spontaneous and UVB-induced skin tumors. Expression of p53.R270H exerted dominant-negative effects on latency, multiplicity, and progression status of UVB-induced but not spontaneous tumors. Surprisingly, gain-of-function properties of p53.R270H were not detected in skin epithelium. Apparently, dominant-negative and gain-of-function effects of mutant p53 are highly tissue specific and become most manifest upon stabilization of p53 after DNA damage.
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Affiliation(s)
- Susan W P Wijnhoven
- Laboratory of Toxicology, Pathology and Genetics, National Institute of Public Health and the Environment, Bilthoven, the Netherlands
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Abstract
The tumor suppressor p53 plays a central role in the DNA damage response. After exposure to genotoxic stress, p53 can both positively and negatively regulate cell fate. Initially, p53 promotes cell survival by inducing cell cycle arrest, DNA repair, and other pro-survival pathways. However, when cells accumulate DNA damage or demonstrate aberrant growth, p53 can direct the elimination of damaged cells. In this review, we will discuss the transcriptional-dependent and -independent roles of p53 in regulating the DNA damage response.
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Affiliation(s)
- E Scott Helton
- Department of Cell Biology, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
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48
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Foster BL, Popowics TE, Fong HK, Somerman MJ. Advances in defining regulators of cementum development and periodontal regeneration. Curr Top Dev Biol 2007; 78:47-126. [PMID: 17338915 DOI: 10.1016/s0070-2153(06)78003-6] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Substantial advancements have been made in defining the cells and molecular signals that guide tooth crown morphogenesis and development. As a result, very encouraging progress has been made in regenerating crown tissues by using dental stem cells and recombining epithelial and mesenchymal tissues of specific developmental ages. To date, attempts to regenerate a complete tooth, including the critical periodontal tissues of the tooth root, have not been successful. This may be in part due to a lesser degree of understanding of the events leading to the initiation and development of root and periodontal tissues. Controversies still exist regarding the formation of periodontal tissues, including the origins and contributions of cells, the cues that direct root development, and the potential of these factors to direct regeneration of periodontal tissues when they are lost to disease. In recent years, great strides have been made in beginning to identify and characterize factors contributing to formation of the root and surrounding tissues, that is, cementum, periodontal ligament, and alveolar bone. This review focuses on the most exciting and important developments over the last 5 years toward defining the regulators of tooth root and periodontal tissue development, with special focus on cementogenesis and the potential for applying this knowledge toward developing regenerative therapies. Cells, genes, and proteins regulating root development are reviewed in a question-answer format in order to highlight areas of progress as well as areas of remaining uncertainty that warrant further study.
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Affiliation(s)
- Brian L Foster
- Department of Periodontics, School of Dentistry, University of Washington, Seattle, Washington 98195, USA
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Römer L, Klein C, Dehner A, Kessler H, Buchner J. p53 – ein natürlicher Krebskiller: Einsichten in die Struktur und Therapiekonzepte. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200600611] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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50
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Römer L, Klein C, Dehner A, Kessler H, Buchner J. p53—A Natural Cancer Killer: Structural Insights and Therapeutic Concepts. Angew Chem Int Ed Engl 2006; 45:6440-60. [PMID: 16983711 DOI: 10.1002/anie.200600611] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Every single day, the DNA of each cell in the human body is mutated thousands of times, even in absence of oncogenes or extreme radiation. Many of these mutations could lead to cancer and, finally, death. To fight this, multicellular organisms have evolved an efficient control system with the tumor-suppressor protein p53 as the central element. An intact p53 network ensures that DNA damage is detected early on. The importance of p53 for preventing cancer is highlighted by the fact that p53 is inactivated in more than 50 % of all human tumors. Thus, for good reason, p53 is one of the most intensively studied proteins. Despite the great effort that has been made to characterize this protein, the complex function and the structural properties of p53 are still only partially known. This review highlights basic concepts and recent progress in understanding the structure and regulation of p53, focusing on emerging new mechanistic and therapeutic concepts.
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Affiliation(s)
- Lin Römer
- Department Chemie, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
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