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Peuget S, Zhou X, Selivanova G. Translating p53-based therapies for cancer into the clinic. Nat Rev Cancer 2024; 24:192-215. [PMID: 38287107 DOI: 10.1038/s41568-023-00658-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/12/2023] [Indexed: 01/31/2024]
Abstract
Inactivation of the most important tumour suppressor gene TP53 occurs in most, if not all, human cancers. Loss of functional wild-type p53 is achieved via two main mechanisms: mutation of the gene leading to an absence of tumour suppressor activity and, in some cases, gain-of-oncogenic function; or inhibition of the wild-type p53 protein mediated by overexpression of its negative regulators MDM2 and MDMX. Because of its high potency as a tumour suppressor and the dependence of at least some established tumours on its inactivation, p53 appears to be a highly attractive target for the development of new anticancer drugs. However, p53 is a transcription factor and therefore has long been considered undruggable. Nevertheless, several innovative strategies have been pursued for targeting dysfunctional p53 for cancer treatment. In mutant p53-expressing tumours, the predominant strategy is to restore tumour suppressor function with compounds acting either in a generic manner or otherwise selective for one or a few specific p53 mutations. In addition, approaches to deplete mutant p53 or to target vulnerabilities created by mutant p53 expression are currently under development. In wild-type p53 tumours, the major approach is to protect p53 from the actions of MDM2 and MDMX by targeting these negative regulators with inhibitors. Although the results of at least some clinical trials of MDM2 inhibitors and mutant p53-restoring compounds are promising, none of the agents has yet been approved by the FDA. Alternative strategies, based on a better understanding of p53 biology, the mechanisms of action of compounds and treatment regimens as well as the development of new technologies are gaining interest, such as proteolysis-targeting chimeras for MDM2 degradation. Other approaches are taking advantage of the progress made in immune-based therapies for cancer. In this Review, we present these ongoing clinical trials and emerging approaches to re-evaluate the current state of knowledge of p53-based therapies for cancer.
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Affiliation(s)
- Sylvain Peuget
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Xiaolei Zhou
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Galina Selivanova
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
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He J, Xi X, Cao P, Zhou J, Liu H, Li N. Long non-coding RNA GNAS-AS1 knockdown inhibits proliferation and epithelial-mesenchymal transition of lung adenocarcinoma cells via the microRNA-433-3p/Rab3A axis. Open Med (Wars) 2023; 18:20230740. [PMID: 37465347 PMCID: PMC10350893 DOI: 10.1515/med-2023-0740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 03/30/2023] [Accepted: 05/31/2023] [Indexed: 07/20/2023] Open
Abstract
The goal of this study was to demonstrate the functions and specific mechanism of long non-coding RNA (lncRNA) GNAS-AS1 in lung adenocarcinoma. Levels of lncRNA GNAS-AS1, microRNA (miR)-433-3p, and Rab3A were assessed by quantitative real-time PCR (qRT-PCR). The target-binding sites of lncRNA GNAS-AS1, miR-433-3p, and Rab3A were predicted and confirmed by bioinformatics tool (StarBase) and a dual-luciferase reporter system. Cell proliferation and apoptosis were checked using MTT and flow cytometry, respectively. Additionally, the levels of apoptosis-related and epithelial-mesenchymal transition (EMT)-associated genes in A549 cells were analyzed by qRT-PCR and western blot. We found that lncRNA GNAS-AS1 was upregulated, miR-433-3p was low-expressed, and Rab3A was overexpressed in lung adenocarcinoma tissues and cell lines. LncRNA GNAS-AS1 interacted with miR-433-3p and negatively regulated miR-433-3p levels. Rab3A was a direct target of miR-433-3p. Downregulation of lncRNA GNAS-AS1 remarkably suppressed cell proliferation, promoted cell apoptosis, decreased B-cell lymphoma-2 (Bcl-2) expression, enhanced the Bcl-2-Associated X (Bax) level, promoted E-cadherin expression, and reduced N-cadherin and Rab3A levels. However, the miR-433-3p inhibitor reversed all these findings. Similarly, the inhibitory effects of miR-433-3p mimic on A549 cells were reversed by the Rab3A-plasmid. In conclusion, lncRNA GNAS-AS1 downregulation suppressed lung adenocarcinoma cell proliferation and EMT through the miR-433-3p/Rab3A axis.
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Affiliation(s)
- Jing He
- Department of Thoracic Surgery, Taixing People’s Hospital, Taixing, 225400, China
| | - Xiaoxiang Xi
- Department of Thoracic Surgery, Taixing People’s Hospital, No. 1 Changzheng Road, Taixing Town, Taixing, 225400, China
| | - Peng Cao
- Department of Thoracic Surgery, Taixing People’s Hospital, Taixing, 225400, China
| | - Jinxia Zhou
- Department of Thoracic Surgery, Taixing People’s Hospital, Taixing, 225400, China
| | - Hui Liu
- Department of Thoracic Surgery, Taixing People’s Hospital, Taixing, 225400, China
| | - Na Li
- Department of Thoracic Surgery, Taixing People’s Hospital, Taixing, 225400, China
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Grinkevich VV, Vema A, Fawkner K, Issaeva N, Andreotti V, Dickinson ER, Hedström E, Spinnler C, Inga A, Larsson LG, Karlén A, Wilhelm M, Barran PE, Okorokov AL, Selivanova G, Zawacka-Pankau JE. Novel Allosteric Mechanism of Dual p53/MDM2 and p53/MDM4 Inhibition by a Small Molecule. Front Mol Biosci 2022; 9:823195. [PMID: 35720128 PMCID: PMC9198586 DOI: 10.3389/fmolb.2022.823195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 04/26/2022] [Indexed: 01/26/2023] Open
Abstract
Restoration of the p53 tumor suppressor for personalised cancer therapy is a promising treatment strategy. However, several high-affinity MDM2 inhibitors have shown substantial side effects in clinical trials. Thus, elucidation of the molecular mechanisms of action of p53 reactivating molecules with alternative functional principle is of the utmost importance. Here, we report a discovery of a novel allosteric mechanism of p53 reactivation through targeting the p53 N-terminus which promotes inhibition of both p53/MDM2 (murine double minute 2) and p53/MDM4 interactions. Using biochemical assays and molecular docking, we identified the binding site of two p53 reactivating molecules, RITA (reactivation of p53 and induction of tumor cell apoptosis) and protoporphyrin IX (PpIX). Ion mobility-mass spectrometry revealed that the binding of RITA to serine 33 and serine 37 is responsible for inducing the allosteric shift in p53, which shields the MDM2 binding residues of p53 and prevents its interactions with MDM2 and MDM4. Our results point to an alternative mechanism of blocking p53 interaction with MDM2 and MDM4 and may pave the way for the development of novel allosteric inhibitors of p53/MDM2 and p53/MDM4 interactions.
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Affiliation(s)
- Vera V. Grinkevich
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Aparna Vema
- Division of Organic Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Karin Fawkner
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Natalia Issaeva
- Department of Otolaryngology/Head and Neck Surgery, UNC-Chapel Hill, Chapel Hill, NC, United States
| | - Virginia Andreotti
- IRCCS Ospedale Policlinico San Martino, Genetics of Rare Cancers, Genoa, Italy
| | - Eleanor R. Dickinson
- Manchester Institute of Biotechnology, The School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Elisabeth Hedström
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Clemens Spinnler
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Alberto Inga
- Department CIBIO, University of Trento, Trento, Italy
| | - Lars-Gunnar Larsson
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Anders Karlén
- Division of Organic Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Margareta Wilhelm
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Perdita E. Barran
- Manchester Institute of Biotechnology, The School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Andrei L. Okorokov
- Wolfson Institute for Biomedical Research, University College London, London, United Kingdom
| | - Galina Selivanova
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden,*Correspondence: Galina Selivanova, ; Joanna E. Zawacka-Pankau,
| | - Joanna E. Zawacka-Pankau
- Department of Medicine, Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institute, Stockholm, Sweden,*Correspondence: Galina Selivanova, ; Joanna E. Zawacka-Pankau,
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Anti-Cancer Mechanisms of Taurine in Human Nasopharyngeal Carcinoma Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1155:533-541. [DOI: 10.1007/978-981-13-8023-5_49] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Ye YT, Zhong W, Sun P, Wang D, Wang C, Hu LM, Qian JQ. Apoptosis induced by the methanol extract of Salvia miltiorrhiza Bunge in non-small cell lung cancer through PTEN-mediated inhibition of PI3K/Akt pathway. JOURNAL OF ETHNOPHARMACOLOGY 2017; 200:107-116. [PMID: 28088493 DOI: 10.1016/j.jep.2016.12.051] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 11/30/2016] [Accepted: 12/30/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Salvia miltiorrhiza Bunge, a well-known traditional Chinese medicinal (TCM) plant, has been used to treat cardiovascular diseases since thousands of years. Many studies reported that the active component tanshinones displayed a variety of biological activities: anti-thrombous, anti-allergic, anti-inflammatory, antioxidant and anti-tumor promoting. But the mechanism of how the active components working still need to be clarified. The anti-tumor effect of compounds of tanshinone (CTN), the methanol extract of Salvia miltiorrhiza Bunge roots, was investigated. The aim of this study was to investigate the effects of CTN on the growth inhibition, apoptosis and molecular targets of human non-small cell lung cancer (NSCLC). MATERIALS AND METHODS CTN-induced cytotoxicity was determined by MTT assay. The cell survival was evaluated using clonogenic survival assay. The morphology of Glc-82 cells after treatment with CTN was determined by fluorescence microscopy. Cell cycle distribution was revealed by flow cytometry. The apoptotic cells were quantified with annexin V-FITC/PI staining and flow cytometry, and observed using Hoechst 33258 staining and TUNEL assays. The expression levels of proteins were analyzed using western blot. Tumor growth was assessed by subcutaneous inoculation of cells into BALB/c nude mice. RESULTS CTN inhibited the proliferation of NSCLC in a dose-dependent manner and induced both early and late apoptosis. Treatment of Glc-82 cells with CTN (5-80μg/ml) significantly (p<0.05) suppressed the cell proliferation in a concentration and time-dependent manner. CTN induced significant (p<0.05) and dose-dependent apoptosis of Glc-82 cells. Cell cycle assay showed that CTN induced a G2/M phase arrest, and significantly (p<0.05) increased expression of p53 and p21, actived caspase-3/9 and PARP1, which suggest the involvement of the mitochondria in the apoptotic signals. In addition, CTN decreased expression of the anti-apoptotic protein Bcl-2, Bcl-xl and increased expression of the pro-apoptotic protein Bax. Result also showed that CTN could increase expression levels of PTEN, and reduce the phosphorylated levels of Akt (protein kinase B) on Thr 308 and Ser 473 domain. In vivo assay showed that the antitumor effect of CTN was significantly augmented without increasing toxicity in nude mice bearing Glc-82 xenograft. CONCLUSION The PTEN/Akt signaling axis is defined as a critical pathway regulated by PTEN in NSCLC. CTN, the methanol extract of Salvia miltiorrhiza Bunge, are the active compounds as shown by their ability to induce apoptosis through the mitochondrial pathway of apoptosis and PTEN-mediated inhibition of PI3K/Akt pathway. CTN could inhibit tumor growth more efficiently, which supports the ethno-medicinal use of this herb as an alternative or complementary therapy for NSCLC.
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Affiliation(s)
- Yin-Tao Ye
- Department of pharmacy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China; Institute of Chinese Medicine Research, Tianjin University of Traditional Chinese medicine, Tianjin, 300193, China
| | - Wei Zhong
- Glaxo Smith Kline, Tianjin Smith Kline & French Laboratories Ltd, Tianjin 300163, China
| | - Pei Sun
- Department of pharmacy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China
| | - Dong Wang
- Department of pharmacy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China
| | - Chen Wang
- Department of pharmacy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China
| | - Li-Min Hu
- Institute of Chinese Medicine Research, Tianjin University of Traditional Chinese medicine, Tianjin, 300193, China
| | - Jun-Qiang Qian
- Department of pharmacy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China
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p53 efficiently suppresses tumor development in the complete absence of its cell-cycle inhibitory and proapoptotic effectors p21, Puma, and Noxa. Cell Rep 2013; 3:1339-45. [PMID: 23665218 DOI: 10.1016/j.celrep.2013.04.012] [Citation(s) in RCA: 208] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 04/03/2013] [Accepted: 04/12/2013] [Indexed: 12/17/2022] Open
Abstract
Activation of apoptosis through transcriptional induction of Puma and Noxa has long been considered to constitute the critical (if not sole) process by which p53 suppresses tumor development, although G1/S boundary cell-cycle arrest via induction of the CDK inhibitor p21 has also been thought to contribute. Recent analyses of mice bearing mutations that impair p53-mediated induction of select target genes have indicated that activation of apoptosis and G1/S cell-cycle arrest may, in fact, be dispensable for p53-mediated tumor suppression. However, the expression of Puma, Noxa, and p21 was not abrogated in these mutants, only reduced; therefore, the possibility that the reduced levels of these critical effectors of p53-mediated apoptosis and G1/S-cell-cycle arrest sufficed to prevent tumorigenesis could not be excluded. To resolve this important issue, we have generated mice deficient for p21, Puma, and Noxa (p21-/-puma-/-noxa-/- mice). Cells from these mice were deficient in their ability to undergo p53-mediated apoptosis, G1/S cell-cycle arrest, and senescence. Nonetheless, these animals remained tumor free until at least 500 days, in contrast to p53-deficient mice, which had all succumbed to lymphoma or sarcoma by 250 days. Interestingly, DNA lesions induced by γ-irradiation persisted longer in p53-deficient cells compared to wild-type or p21-/-puma-/-noxa-/- cells, and the former failed to transcriptionally activate several p53 target genes implicated in DNA repair. These results demonstrate beyond a doubt that the induction of apoptosis, cell-cycle arrest, and possibly senescence is dispensable for p53-mediated suppression of spontaneous tumor development and indicate that coordination of genomic stability and possibly other processes, such as metabolic adaptation, may instead be critical.
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Ye Y, Xu W, Zhong W, Li Y, Wang C. Combination treatment with dihydrotanshinone I and irradiation enhances apoptotic effects in human cervical cancer by HPV E6 down-regulation and caspases activation. Mol Cell Biochem 2011; 363:191-202. [DOI: 10.1007/s11010-011-1171-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Accepted: 11/23/2011] [Indexed: 12/30/2022]
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Olivier M, Hollstein M, Hainaut P. TP53 mutations in human cancers: origins, consequences, and clinical use. Cold Spring Harb Perspect Biol 2010; 2:a001008. [PMID: 20182602 DOI: 10.1101/cshperspect.a001008] [Citation(s) in RCA: 1300] [Impact Index Per Article: 92.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Somatic mutations in the TP53 gene are one of the most frequent alterations in human cancers, and germline mutations are the underlying cause of Li-Fraumeni syndrome, which predisposes to a wide spectrum of early-onset cancers. Most mutations are single-base substitutions distributed throughout the coding sequence. Their diverse types and positions may inform on the nature of mutagenic mechanisms involved in cancer etiology. TP53 mutations are also potential prognostic and predictive markers, as well as targets for pharmacological intervention. All mutations found in human cancers are compiled in the IARC TP53 Database (http://www-p53.iarc.fr/). A human TP53 knockin mouse model (Hupki mouse) provides an experimental model to study mutagenesis in the context of a human TP53 sequence. Here, we summarize current knowledge on TP53 gene variations observed in human cancers and populations, and current clinical applications derived from this knowledge.
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Affiliation(s)
- Magali Olivier
- Group of Molecular Carcinogenesis, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon Cedex 08, France
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Zhu F, Dollé MET, Berton TR, Kuiper RV, Capps C, Espejo A, McArthur MJ, Bedford MT, van Steeg H, de Vries A, Johnson DG. Mouse models for the p53 R72P polymorphism mimic human phenotypes. Cancer Res 2010; 70:5851-9. [PMID: 20587514 DOI: 10.1158/0008-5472.can-09-4646] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The p53 tumor suppressor gene contains a common single nucleotide polymorphism (SNP) that results in either an arginine or proline at position 72 of the p53 protein. This polymorphism affects the apoptotic activity of p53 but the mechanistic basis and physiologic relevance of this phenotypic difference remain unclear. Here, we describe the development of mouse models for the p53 R72P SNP using two different approaches. In both sets of models, the human or humanized p53 proteins are functional as evidenced by the transcriptional induction of p53 target genes in response to DNA damage and the suppression of early lymphomagenesis. Consistent with in vitro studies, mice expressing the 72R variant protein (p53R) have a greater apoptotic response to several stimuli compared with mice expressing the p53P variant. Molecular studies suggest that both transcriptional and nontranscriptional mechanisms may contribute to the differential abilities of the p53 variants to induce apoptosis. Despite a difference in the acute response to UV radiation, no difference in the tumorigenic response to chronic UV exposure was observed between the polymorphic mouse models. These findings suggest that under at least some conditions, the modulation of apoptosis by the R72P polymorphism does not affect the process of carcinogenesis.
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Affiliation(s)
- Feng Zhu
- Department of Carcinogenesis, Science Park-Research Division, The University of Texas MD Anderson Cancer Center, Smithville, Texas 78957, USA
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Kucab JE, Phillips DH, Arlt VM. Linking environmental carcinogen exposure to TP53 mutations in human tumours using the human TP53 knock-in (Hupki) mouse model. FEBS J 2010. [DOI: 10.1111/j.1742-4658.2010.07676.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Odell A, Askham J, Whibley C, Hollstein M. How to become immortal: let MEFs count the ways. Aging (Albany NY) 2010; 2:160-5. [PMID: 20378935 PMCID: PMC2871244 DOI: 10.18632/aging.100129] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 03/17/2010] [Indexed: 02/02/2023]
Abstract
Understanding
the molecular mechanisms and biological consequences of genetic changes
occurring during bypass of cellular senescence spans a broad area of
medical research from the cancer field to regenerative medicine. Senescence
escape and immortalisation have been intensively studied in murine
embryonic fibroblasts as a model system, and are known to occur when the
p53/ARF tumour suppressor pathway is disrupted. We showed recently that murine
fibroblasts with a humanised p53 gene (Hupki cells, from a human p53 knock-in mouse
model) first senesce, and then become immortalised in the same way as their
homologues with normal murine p53. In both cell types, immortalised cultures
frequently sustain either a p53 gene mutation matching a human tumour mutation and
resulting in loss of p53 transcriptional transactivation, or a biallelic deletion
at the p19/ARF locus. Whilst these genetic events were not unexpected, we were
surprised to find that a significant proportion of immortalised cell cultures
apparently had neither a p53 mutation nor loss of p19/ARF. Here we consider
various routes to p53/ARF disruption in senescence bypass, and dysfunction of
other tumour suppressor networks that may contribute to release from tenacious
cell cycle arrest in senescent cultures.
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Affiliation(s)
- Adam Odell
- Faculty of Medicine and Health, University of Leeds, LIGHT Laboratories, Leeds, UK
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Abstract
The normal functioning of p53 is a potent barrier to cancer. Tumour-associated mutations in TP53, typically single nucleotide substitutions in the coding sequence, are a hallmark of most human cancers and cause dramatic defects in p53 function. By contrast, only a small fraction, if any, of the >200 naturally occurring sequence variations (single nucleotide polymorphisms, SNPs) of TP53 in human populations are expected to cause measurable perturbation of p53 function. Polymorphisms in the TP53 locus that might have cancer-related phenotypical manifestations are the subject of this Review. Polymorphic variants of other genes in the p53 pathway, such as MDM2, which might have biological consequences either individually or in combination with p53 variants are also discussed.
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Affiliation(s)
- Catherine Whibley
- Leeds Institute of Genetics, Health and Therapeutics, LIGHT Laboratories, University of Leeds, Leeds, LS2 9JT, UK
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Regulation of apoptosis by Caspases under oxidative stress conditions in mice testicular cells: in vitro molecular mechanism. Mol Cell Biochem 2008; 322:43-52. [DOI: 10.1007/s11010-008-9938-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Accepted: 10/13/2008] [Indexed: 10/21/2022]
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Puca R, Nardinocchi L, Gal H, Rechavi G, Amariglio N, Domany E, Notterman DA, Scarsella M, Leonetti C, Sacchi A, Blandino G, Givol D, D'Orazi G. Reversible Dysfunction of Wild-Type p53 following Homeodomain-Interacting Protein Kinase-2 Knockdown. Cancer Res 2008; 68:3707-14. [DOI: 10.1158/0008-5472.can-07-6776] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Phang BH, Sabapathy K. The codon 72 polymorphism-specific effects of human p53 are absent in mouse cells: implications on generation of mouse models. Oncogene 2006; 26:2964-74. [PMID: 17130838 DOI: 10.1038/sj.onc.1210112] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Human p53, unlike mouse p53, contains a polymorphic site at codon 72 in exon 4 encoding either an arginine amino acid (72R) or a proline residue (72P). The 72R form was shown to induce apoptosis better than the 72P form, partly owing to its ability to efficiently bind to the nuclear-export protein CRM1 and localize to the mitochondria. This polymorphism has also been associated with cancer predisposition and chemo-sensitivity. Further understanding of the in vivo significance of this polymorphism in carcinogenesis requires the generation of mouse models. We have thus evaluated if the polymorphism-specific effects of human p53 are retained in mouse cells. Though being transcriptionally active, both the human polymorphs were found to have lost their ability to differentially suppress growth and bind to CRM1 or MDM2 in mouse cells. Moreover, chimaeric proteins containing mouse exons 2-3 and human exons 4-11 have also lost the polymorphism-specific effects in human cells, suggesting that human exons 2-3 are important in regulating the polymorphism-specific effects. Furthermore, human p53 and the various chimaeric proteins were generally less effective in inhibiting growth of mouse cells compared to mouse p53, suggesting that mouse p53 is more potent than human p53 in suppressing growth, partly due to enhanced binding of MDM2 to human p53. The data together suggest that mouse cells may not provide an appropriate environment for the manifestation of the polymorphism-specific functional differences of human p53, and hence, cautions against the expression of full-length or chimaeric p53 proteins in mice to study the effects of the polymorphism.
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Affiliation(s)
- B H Phang
- Laboratory of Molecular Carcinogenesis, Division of Cellular and Molecular Research, National Cancer Centre, Singapore, Singapore
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