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Song B, Yang P, Zhang S. Cell fate regulation governed by p53: Friends or reversible foes in cancer therapy. Cancer Commun (Lond) 2024; 44:297-360. [PMID: 38311377 PMCID: PMC10958678 DOI: 10.1002/cac2.12520] [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: 07/26/2023] [Revised: 01/03/2024] [Accepted: 01/11/2024] [Indexed: 02/10/2024] Open
Abstract
Cancer is a leading cause of death worldwide. Targeted therapies aimed at key oncogenic driver mutations in combination with chemotherapy and radiotherapy as well as immunotherapy have benefited cancer patients considerably. Tumor protein p53 (TP53), a crucial tumor suppressor gene encoding p53, regulates numerous downstream genes and cellular phenotypes in response to various stressors. The affected genes are involved in diverse processes, including cell cycle arrest, DNA repair, cellular senescence, metabolic homeostasis, apoptosis, and autophagy. However, accumulating recent studies have continued to reveal novel and unexpected functions of p53 in governing the fate of tumors, for example, functions in ferroptosis, immunity, the tumor microenvironment and microbiome metabolism. Among the possibilities, the evolutionary plasticity of p53 is the most controversial, partially due to the dizzying array of biological functions that have been attributed to different regulatory mechanisms of p53 signaling. Nearly 40 years after its discovery, this key tumor suppressor remains somewhat enigmatic. The intricate and diverse functions of p53 in regulating cell fate during cancer treatment are only the tip of the iceberg with respect to its equally complicated structural biology, which has been painstakingly revealed. Additionally, TP53 mutation is one of the most significant genetic alterations in cancer, contributing to rapid cancer cell growth and tumor progression. Here, we summarized recent advances that implicate altered p53 in modulating the response to various cancer therapies, including chemotherapy, radiotherapy, and immunotherapy. Furthermore, we also discussed potential strategies for targeting p53 as a therapeutic option for cancer.
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Affiliation(s)
- Bin Song
- Laboratory of Radiation MedicineWest China Second University HospitalSichuan UniversityChengduSichuanP. R. China
| | - Ping Yang
- Laboratory of Radiation MedicineWest China Second University HospitalSichuan UniversityChengduSichuanP. R. China
| | - Shuyu Zhang
- Laboratory of Radiation MedicineWest China Second University HospitalSichuan UniversityChengduSichuanP. R. China
- The Second Affiliated Hospital of Chengdu Medical CollegeChina National Nuclear Corporation 416 HospitalChengduSichuanP. R. China
- Laboratory of Radiation MedicineNHC Key Laboratory of Nuclear Technology Medical TransformationWest China School of Basic Medical Sciences & Forensic MedicineSichuan UniversityChengduSichuanP. R. China
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2
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EAPB0503, an Imidazoquinoxaline Derivative Modulates SENP3/ARF Mediated SUMOylation, and Induces NPM1c Degradation in NPM1 Mutant AML. Int J Mol Sci 2022; 23:ijms23073421. [PMID: 35408798 PMCID: PMC8998649 DOI: 10.3390/ijms23073421] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/14/2022] [Accepted: 03/18/2022] [Indexed: 12/14/2022] Open
Abstract
Nucleophosmin-1 (NPM1) is a pleiotropic protein involved in numerous cellular processes. NPM1 shuttles between the nucleus and the cytoplasm, but exhibits a predominant nucleolar localization, where its fate and functions are exquisitely controlled by dynamic post-translational modifications (PTM). Sentrin/SUMO Specific Peptidase 3 (SENP3) and ARF are two nucleolar proteins involved in NPM1 PTMs. SENP3 antagonizes ARF-mediated NPM1 SUMOylation, to promote ribosomal biogenesis. In Acute Myeloid Leukemia (AML), NPM1 is frequently mutated, and exhibits an aberrant cytoplasmic localization (NPM1c). NPM1c mutations define a separate AML entity with good prognosis in some AML patients, rendering NPM1c as a potential therapeutic target. SENP3-mediated NPM1 de-SUMOylation induces resistance to therapy in NPM1c AML. Here, we demonstrate that the imidazoquinoxaline EAPB0503 prolongs the survival and results in selective reduction in the leukemia burden of NPM1c AML xenograft mice. Indeed, EAPB0503 selectively downregulates HDM2 expression and activates the p53 pathway in NPM1c expressing cells, resulting in apoptosis. Importantly, we unraveled that NPM1c expressing cells exhibit low basal levels of SUMOylation paralleled with high SENP3 and low ARF basal levels. EAPB0503 reverted these molecular players by inducing NPM1c SUMOylation and ubiquitylation, leading to its proteasomal degradation. EAPB0503-induced NPM1c SUMOylation is concurrent with SENP3 downregulation and ARF upregulation in NPM1c expressing cells. Collectively, these results provide a strong rationale for testing therapies modulating NPM1c post-translational modifications in the management of NPM1c AML.
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3
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Epigenetics of Cutaneous Sarcoma. Int J Mol Sci 2021; 23:ijms23010422. [PMID: 35008848 PMCID: PMC8745302 DOI: 10.3390/ijms23010422] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/25/2021] [Accepted: 12/28/2021] [Indexed: 12/13/2022] Open
Abstract
Epigenetic changes influence various physiological and pathological conditions in the human body. Recent advances in epigenetic studies of the skin have led to an appreciation of the importance of epigenetic modifications in skin diseases. Cutaneous sarcomas are intractable skin cancers, and there are no curative therapeutic options for the advanced forms of cutaneous sarcomas. In this review, we discuss the detailed molecular effects of epigenetic modifications on skin sarcomas, such as dermatofibrosarcoma protuberans, angiosarcoma, Kaposi's sarcoma, leiomyosarcoma, and liposarcoma. We also discuss the application of epigenetic-targeted therapy for skin sarcomas.
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Sciot R. MDM2 Amplified Sarcomas: A Literature Review. Diagnostics (Basel) 2021; 11:diagnostics11030496. [PMID: 33799733 PMCID: PMC8001728 DOI: 10.3390/diagnostics11030496] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 01/10/2023] Open
Abstract
Murine Double Minute Clone 2, located at 12q15, is an oncogene that codes for an oncoprotein of which the association with p53 was discovered 30 years ago. The most important function of MDM2 is to control p53 activity; it is in fact the best documented negative regulator of p53. Mutations of the tumor suppressor gene p53 represent the most frequent genetic change in human cancers. By overexpressing MDM2, cancer cells have another means to block p53. The sarcomas in which MDM2 amplification is a hallmark are well-differentiated liposarcoma/atypical lipomatous tumor, dedifferentiated liposarcoma, intimal sarcoma, and low-grade osteosarcoma. The purpose of this review is to summarize the typical clinical, histopathological, immunohistochemical, and genetic features of these tumors.
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Affiliation(s)
- Raf Sciot
- Department of Pathology, University Hospital, University of Leuven, 3000 Leuven, Belgium
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Triangular Relationship between p53, Autophagy, and Chemotherapy Resistance. Int J Mol Sci 2020; 21:ijms21238991. [PMID: 33256191 PMCID: PMC7730978 DOI: 10.3390/ijms21238991] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/23/2020] [Accepted: 11/23/2020] [Indexed: 12/11/2022] Open
Abstract
Chemotherapy and radiation often induce a number of cellular responses, such as apoptosis, autophagy, and senescence. One of the major regulators of these processes is p53, an essential tumor suppressor that is often mutated or lost in many cancer types and implicated in early tumorigenesis. Gain of function (GOF) p53 mutations have been implicated in increased susceptibility to drug resistance, by compromising wildtype anti-tumor functions of p53 or modulating key p53 processes that confer chemotherapy resistance, such as autophagy. Autophagy, a cellular survival mechanism, is initially induced in response to chemotherapy and radiotherapy, and its cytoprotective nature became the spearhead of a number of clinical trials aimed to sensitize patients to chemotherapy. However, increased pre-clinical studies have exemplified the multifunctional role of autophagy. Additionally, compartmental localization of p53 can modulate induction or inhibition of autophagy and may play a role in autophagic function. The duality in p53 function and its effects on autophagic function are generally not considered in clinical trial design or clinical therapeutics; however, ample pre-clinical studies suggest they play a role in tumor responses to therapy and drug resistance. Further inquiry into the interconnection between autophagy and p53, and its effects on chemotherapeutic responses may provide beneficial insights on multidrug resistance and novel treatment regimens for chemosensitization.
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Lozano G. Restoring p53 in cancer: the promises and the challenges. J Mol Cell Biol 2020; 11:615-619. [PMID: 31283825 PMCID: PMC6736346 DOI: 10.1093/jmcb/mjz063] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 06/24/2019] [Indexed: 12/20/2022] Open
Affiliation(s)
- Guillermina Lozano
- Department of Genetics, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Correspondence to: Guillermina Lozano, E-mail:
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El-Mekkawy HI, Al-Kahtani MA, Shati AA, Alshehri MA, Al-Doaiss AA, Elmansi AA, Ahmed AE. Black tea and curcumin synergistically mitigate the hepatotoxicity and nephropathic changes induced by chronic exposure to aflatoxin-B1 in Sprague-Dawley rats. J Food Biochem 2020; 44:e13346. [PMID: 32602579 DOI: 10.1111/jfbc.13346] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/25/2020] [Accepted: 05/28/2020] [Indexed: 01/18/2023]
Abstract
The study aimed to clarify the characteristics of black tea (BTE) and/or curcumin (CMN) against aflatoxin-B1 (AFB1). Forty eight adult male Sprague-Dawley rats were divided into eight groups. G1 was non-treated control. G2, G3, and G4 were olive oil, BTE, and CMN, respectively. G5 was olive oil-dissolved AFB1 (25 µg/kg b.w). G6, G7, and G8 were AFB1 along with BTE (2%), CMN (200 mg/kg b.w.), and BTE plus CMN, respectively. All treatments were orally given for consecutive 90 days. After treatment period, rats were sacrificed. Serobiochemical analysis and histopathology showed hepatorenal dysfunction in response to AFB1. Glutathione-antioxidants were significantly decreased versus increased lipid peroxides (p < .05-.001). AFB1 significantly increased the expression of the antitumor p53, but decreased that of antiapoptotic Bcl2 in liver or kidney tissue, either (p < .05). BTE or CMN ameliorated those changes induced by AFB1 in both liver and kidney with highly pronounced improvement when combined BTE/CMN was used. PRACTICAL APPLICATIONS: Black tea (BTE) and curcumin (CMN) were known for their antioxidant effects, and several studies reported their independent effects against different toxicities including aflatoxicosis. The current study clarifies the ameliorative characteristics of both agents; BTE and/or CMN, against the toxicity resulted from the chronic exposure to aflatoxin-B1 (AFB1) (25 µg/kg b.w. for consecutive 90 days). The dose of either agents, BTE or CMN, was 200 mg/kg b.w. along with AFB1. The pathologic changes, serobiochemical parameters, oxidative stress, histological changes, and the molecular disruption, induced by AFB1 in both liver and kidney were obviously and significantly ameliorated after BTE and/or CMN treatments in variable potencies where both agents showed the most effective antitoxic capacities.
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Affiliation(s)
- Haitham I El-Mekkawy
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia
| | - Mohammed A Al-Kahtani
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia
| | - Ali A Shati
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia
| | - Mohammed A Alshehri
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia
| | - Amin A Al-Doaiss
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia.,Department of Histology and Anatomy, Faculty of Medicine, Sana'a University, Sana'a, Republic of Yemen
| | - Ahmed A Elmansi
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia.,Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Ahmed Ezzat Ahmed
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia.,Department of Theriogenology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt
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Expression of the Long Noncoding RNA DINO in Human Papillomavirus-Positive Cervical Cancer Cells Reactivates the Dormant TP53 Tumor Suppressor through ATM/CHK2 Signaling. mBio 2020; 11:mBio.01190-20. [PMID: 32546626 PMCID: PMC7298716 DOI: 10.1128/mbio.01190-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Functional restoration of the TP53 tumor suppressor holds great promise for anticancer therapy. Current strategies are focused on modulating TP53 regulatory proteins. Long noncoding RNAs (lncRNAs) have emerged as important regulators of TP53 as well as modulators of downstream tumor-suppressive transcriptional responses. Unlike many other cancer types, human papillomavirus (HPV)-positive cancer cells retain wild-type TP53 that is rendered dysfunctional by the viral E6 protein. We show that acute expression of the damage-induced long noncoding RNA, DINO, a known TP53 transcriptional target and functional modulator, causes TP53 reactivation in HPV-positive cervical cancer cells. This causes increased vulnerability to standard chemotherapeutics as well as biguanide compounds that cause metabolic stress. Hence, strategies that target DINO may be useful for restoring TP53 tumor suppressor activity in HPV-positive cancers and other tumor types that retain wild-type TP53. Tumor cells overcome the cytostatic and cytotoxic restraints of TP53 tumor suppressor signaling through a variety of mechanisms. High-risk human papillomavirus (HPV)-positive tumor cells retain wild-type TP53 because the HPV E6/UBE3A ubiquitin ligase complex targets TP53 for proteasomal degradation. While restoration of TP53 in tumor cells holds great promise for cancer therapy, attempts to functionally restore the dormant TP53 tumor suppressor in HPV-positive cancer cells by inhibiting the HPV E6/UBE3A ubiquitin ligase complex have not yet been successful. The damage-induced long noncoding RNA, DINO (DINOL), is a TP53 transcriptional target that has been reported to bind to and stabilize TP53, thereby amplifying TP53 signaling. We show that HPV-positive cervical carcinoma cells contain low levels of DINO because of HPV E6/UBE3A-mediated TP53 degradation. Acute DINO expression overrides HPV16 E6/UBE3A-mediated TP53 degradation, causing TP53 stabilization and increased expression of TP53 transcriptional target genes. This causes a marked sensitization to chemotherapy agents and renders cells vulnerable to metabolic stress. Acute DINO expression in HPV-positive cervical cancer cells induces hallmarks of DNA damage response signaling, and TP53 activation involves ATM/CHK2 signaling. DINO upregulation in response to DNA damage is independent of ATM/CHK2 and can occur in cancer cells that express mutant TP53.
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Song Y, Zhang L, Jiang Y, Hu T, Zhang D, Qiao Q, Wang R, Wang M, Han S. MTBP regulates cell survival and therapeutic sensitivity in TP53 wildtype glioblastomas. Am J Cancer Res 2019; 9:6019-6030. [PMID: 31534534 PMCID: PMC6735364 DOI: 10.7150/thno.35747] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/25/2019] [Indexed: 01/21/2023] Open
Abstract
Background: Glioblastoma (GBM) is highly proliferative and resistant to radio-chemotherapy. Loss of tumor suppressor gene TP53 function frequently occurs at protein level in GBMs. This inhibition is often mediated by other components within the p53 signaling axis, including MDM2, whose binding protein (MTBP) plays an important role in the regulation of MDM2 and p53 activity. We investigated the role of MTBP in the biology of TP53-wildtype (TP53wt) GBMs. Methods: MTBP expression was examined in TCGA and REMBRANDT datasets. MTBP was silenced or overexpressed in TP53wt GBM cells and glioma stem cells (GSCs). The effects on cell viability, apoptosis, and clonogenicity were assessed. The transcriptional regulation of MTBP was investigated. Results: Upregulation of MTBP was correlated with the Classical molecular subtype, and it predicted poor survival. In TP53wt GBM cells, the protein levels of MTBP were positively associated with those of MDM2 but negatively correlated with those of p53. MTBP knockdown promoted apoptosis and inhibited clonogenicity, while overexpression of this protein enhanced tumorigenicity in vitro and in vivo. The pro-survival effect of MTBP depended on the activity of MDM2 and p53. MTBP was transcriptionally regulated by c-myc, thereby forming a positive regulatory loop. Finally, MTBP silencing increased the sensitivity of TP53wt GSCs to radiation and TMZ treatment in vitro and in vivo. Conclusion: MTBP regulates the cell survival and treatment sensitivity of TP53wt GBMs through MDM2-dependent post-translational modification of p53. MTBP-targeting treatments are potentially useful in increasing patients' survival.
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10
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Thoenen E, Curl A, Iwakuma T. TP53 in bone and soft tissue sarcomas. Pharmacol Ther 2019; 202:149-164. [PMID: 31276706 DOI: 10.1016/j.pharmthera.2019.06.010] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 06/25/2019] [Indexed: 12/13/2022]
Abstract
Genomic and functional study of existing and emerging sarcoma targets, such as fusion proteins, chromosomal aberrations, reduced tumor suppressor activity, and oncogenic drivers, is broadening our understanding of sarcomagenesis. Among these mechanisms, the tumor suppressor p53 (TP53) plays significant roles in the suppression of bone and soft tissue sarcoma progression. Although mutations in TP53 were thought to be relatively low in sarcomas, modern techniques including whole-genome sequencing have recently illuminated unappreciated alterations in TP53 in osteosarcoma. In addition, oncogenic gain-of-function activities of missense mutant p53 (mutp53) have been reported in sarcomas. Moreover, new targeting strategies for TP53 have been discovered: restoration of wild-type p53 (wtp53) activity through inhibition of TP53 negative regulators, reactivation of the wtp53 activity from mutp53, depletion of mutp53, and targeting of vulnerabilities in cells with TP53 deletions or mutations. These discoveries enable development of novel therapeutic strategies for therapy-resistant sarcomas. We have outlined nine bone and soft tissue sarcomas for which TP53 plays a crucial tumor suppressive role. These include osteosarcoma, Ewing sarcoma, chondrosarcoma, rhabdomyosarcoma (RMS), leiomyosarcoma (LMS), synovial sarcoma, liposarcoma (LPS), angiosarcoma, and undifferentiated pleomorphic sarcoma (UPS).
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Affiliation(s)
- Elizabeth Thoenen
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66010, USA
| | - Amanda Curl
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66010, USA
| | - Tomoo Iwakuma
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66010, USA; Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66010, USA; Translational Laboratory Oncology Research, Children's Mercy Research Institute, Kansas City, MO 64108, USA.
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11
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Harbhajanka A, Dahoud W, Michael CW, Elliot R. Cytohistological correlation, immunohistochemistry and Murine Double Minute Clone 2 amplification of pulmonary artery intimal sarcoma: A case report with review of literature. Diagn Cytopathol 2018; 47:494-497. [PMID: 30552756 DOI: 10.1002/dc.24131] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/26/2018] [Accepted: 11/27/2018] [Indexed: 01/10/2023]
Abstract
Pulmonary artery intimal sarcoma is a rare aggressive intraluminal tumor often misdiagnosed as acute or chronic pulmonary thromboembolism due to its clinical presentation and radiological findings. Thus early diagnosis is very crucial and may improve patient outcome. There is limited literature on diagnosis of pulmonary artery sarcoma by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). Herein, we report a case of mass-like lesion in the PA diagnosed on cytological material obtained by EBUS-TBNA with rapid on-site evaluation (ROSE). The aspirate showed pleomorphic malignant spindled cells arranged in loosely cohesive clusters. The intraluminal origin of PAIS was supported by radiographic findings. Subsequently, the patient received preoperative chemotherapy and underwent tumor resection with reconstruction. This report describes the cytomorphologic features of this rare intravascular tumor and demonstrates how limited cytological sample obtained from EBUS-TBNA with ROSE can be triaged efficiently for ancillary studies like immunohistochemistry and MDM2 amplification, thus expediting the management.
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Affiliation(s)
- Aparna Harbhajanka
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH
| | - Wissam Dahoud
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH
| | - Claire W Michael
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH
| | - Robin Elliot
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH
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Berberich A, Kessler T, Thomé CM, Pusch S, Hielscher T, Sahm F, Oezen I, Schmitt LM, Ciprut S, Hucke N, Ruebmann P, Fischer M, Lemke D, Breckwoldt MO, von Deimling A, Bendszus M, Platten M, Wick W. Targeting Resistance against the MDM2 Inhibitor RG7388 in Glioblastoma Cells by the MEK Inhibitor Trametinib. Clin Cancer Res 2018; 25:253-265. [DOI: 10.1158/1078-0432.ccr-18-1580] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 08/07/2018] [Accepted: 09/27/2018] [Indexed: 11/16/2022]
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13
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Kim J, Park SH, Do KH, Kim D, Moon Y. Interference with mutagenic aflatoxin B1-induced checkpoints through antagonistic action of ochratoxin A in intestinal cancer cells: a molecular explanation on potential risk of crosstalk between carcinogens. Oncotarget 2018; 7:39627-39639. [PMID: 27119350 PMCID: PMC5129958 DOI: 10.18632/oncotarget.8914] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 04/05/2016] [Indexed: 12/16/2022] Open
Abstract
Foodborne aflatoxin B1 (AFB1) and ochratoxin A (OTA) cause genotoxic injury and subsequent tumor formation. As a biomarker of oncogenic stimulation by genotoxic mycotoxins, p53-triggered Mdm2 was assessed in intestinal cancer cells. AFB1 increased Mdm2 reporter expression in a dose-dependent manner. However, this was strongly antagonized by OTA treatment. As a positive transcription factor of Mdm2 expression, p53 levels were also increased by AFB1 alone and reduced by OTA. With marginal cell death responses, AFB1 induced p53-mediated S phase arrest and cell cycle-regulating target genes, which was completely suppressed by OTA. Although enterocyte-dominant CYP3A5 counteracted AFB1-induced DNA damage, expression of CYP3A5 was decreased by OTA or AFB1. Instead, OTA enhanced expression of another metabolic inactivating enzyme CYP3A4, attenuation of formation of AFB1-DNA adduct and p53-mediated cell cycle checking responses to the mutagens. Finally, the growth of intestinal cancer cells exposed to the mycotoxin mixture significantly exceeded the expected growth calculated from that of cells treated with each mycotoxin. Although AFB1-induced mutagen formation was decreased by OTA, interference with checkpoints through antagonistic action of OTA may contribute to the survival of tumor cells with deleterious mutations by genotoxic mycotoxins, potently increasing the risk of carcinogenesis.
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Affiliation(s)
- Juil Kim
- Laboratory of Mucosal Exposome and Biomodulation, Department of Biomedical Sciences and Medical Research Institute, Pusan National University School of Medicine, Yangsan, South Korea
| | - Seong-Hwan Park
- Laboratory of Mucosal Exposome and Biomodulation, Department of Biomedical Sciences and Medical Research Institute, Pusan National University School of Medicine, Yangsan, South Korea
| | - Kee Hun Do
- Laboratory of Mucosal Exposome and Biomodulation, Department of Biomedical Sciences and Medical Research Institute, Pusan National University School of Medicine, Yangsan, South Korea
| | - Dongwook Kim
- National Institute of Animal Science, RDA, Wanju, South Korea
| | - Yuseok Moon
- Laboratory of Mucosal Exposome and Biomodulation, Department of Biomedical Sciences and Medical Research Institute, Pusan National University School of Medicine, Yangsan, South Korea.,Research Institute for Basic Sciences and Immunoregulatory Therapeutics Group in Brain Busan 21 Project, Pusan, South Korea
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14
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Lujambio A. To clear, or not to clear (senescent cells)? That is the question. Bioessays 2017; 38 Suppl 1:S56-64. [PMID: 27417123 DOI: 10.1002/bies.201670910] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 11/30/2015] [Accepted: 12/09/2015] [Indexed: 12/22/2022]
Abstract
Cellular senescence is an anti-proliferative program that restricts the propagation of cells subjected to different kinds of stress. Cellular senescence was initially described as a cell-autonomous tumor suppressor mechanism that triggers an irreversible cell cycle arrest that prevents the proliferation of damaged cells at risk of neoplastic transformation. However, discoveries during the last decade have established that senescent cells can also impact the surrounding tissue microenvironment and the neighboring cells in a non-cell-autonomous manner. These non-cell-autonomous activities are, in part, mediated by the selective secretion of extracellular matrix degrading enzymes, cytokines, chemokines and immune modulators, which collectively constitute the senescence-associated secretory phenotype. One of the key functions of the senescence-associated secretory phenotype is to attract immune cells, which in turn can orchestrate the elimination of senescent cells. Interestingly, the clearance of senescent cells seems to be critical to dictate the net effects of cellular senescence. As a general rule, the successful elimination of senescent cells takes place in processes that are considered beneficial, such as tumor suppression, tissue remodeling and embryonic development, while the chronic accumulation of senescent cells leads to more detrimental consequences, namely, cancer and aging. Nevertheless, exceptions to this rule may exist. Now that cellular senescence is in the spotlight for both anti-cancer and anti-aging therapies, understanding the precise underpinnings of senescent cell removal will be essential to exploit cellular senescence to its full potential.
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Affiliation(s)
- Amaia Lujambio
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,Liver Cancer Program, Division of Liver Diseases, Department of Medicine, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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15
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Tackmann NR, Zhang Y. Mouse modelling of the MDM2/MDMX-p53 signalling axis. J Mol Cell Biol 2017; 9:34-44. [PMID: 28096294 PMCID: PMC5907827 DOI: 10.1093/jmcb/mjx006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 01/12/2017] [Indexed: 01/10/2023] Open
Abstract
It is evident that p53 activity is critical for tumour prevention and stress response through its transcriptional activation of genes affecting cellular senescence, apoptosis, cellular metabolism, and DNA repair. The regulation of p53 is highly complex, and MDM2 and MDMX are thought to be critical for deciding the fate of p53, both through inhibitory binding and post-translational modification. Many mouse models have been generated to study the regulation of p53 in vivo, and they have altered our interpretations of how p53 is regulated by MDM2 and MDMX. Although MDM2 is absolutely required for p53 regulation, certain functions are dispensable under unstressed conditions, including the ability of MDM2 to degrade p53. MDMX, on the other hand, may only be required in select situations, like embryogenesis. These models have also clarified how cellular stress signals modify the p53-inhibiting activities of MDM2 and MDMX in vivo. It is clear that more work will need to be performed to further understand the contexts for each of these signals and the requirements of various MDM2 and MDMX functions. Here, we will discuss what we have learned from mouse modelling of MDM2 and MDMX and underscore the ways in which these models could inform future therapies.
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Affiliation(s)
- Nicole R Tackmann
- Department of Radiation Oncology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA.,Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Yanping Zhang
- Department of Radiation Oncology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA.,Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Cancer Institute, Xuzhou Medical College, Xuzhou 221002, China
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16
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Molecular Mechanisms of p53 Deregulation in Cancer: An Overview in Multiple Myeloma. Int J Mol Sci 2016; 17:ijms17122003. [PMID: 27916892 PMCID: PMC5187803 DOI: 10.3390/ijms17122003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 11/14/2016] [Accepted: 11/22/2016] [Indexed: 12/12/2022] Open
Abstract
The p53 pathway is inactivated in the majority of human cancers. Although this perturbation frequently occurs through the mutation or deletion of p53 itself, there are other mechanisms that can attenuate the pathway and contribute to tumorigenesis. For example, overexpression of important p53 negative regulators, such as murine double minute 2 (MDM2) or murine double minute 4 (MDM4), epigenetic deregulation, or even alterations in TP53 mRNA splicing. In this work, we will review the different mechanisms of p53 pathway inhibition in cancer with special focus on multiple myeloma (MM), the second most common hematological malignancy, with low incidence of p53 mutations/deletions but growing evidence of indirect p53 pathway deregulation. Translational implications for MM and cancer prognosis and treatment are also reviewed.
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17
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Pasello G, Urso L, Mencoboni M, Grosso F, Ceresoli GL, Lunardi F, Vuljan SE, Bertorelle R, Sacchetto V, Ciminale V, Rea F, Favaretto A, Conte P, Calabrese F. MDM2 and HIF1alpha expression levels in different histologic subtypes of malignant pleural mesothelioma: correlation with pathological and clinical data. Oncotarget 2016; 6:42053-66. [PMID: 26544728 PMCID: PMC4747209 DOI: 10.18632/oncotarget.5974] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 10/20/2015] [Indexed: 12/29/2022] Open
Abstract
Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis and limited treatment options. Sarcomatoid/biphasic mesotheliomas are characterized by more aggressive behaviour and a poorer prognosis compared with the epithelioid subtype. To date prognostic and tailored therapeutic biomarkers are lacking. The present study analyzed the expression levels of MDM2 and HIF1alpha in different histologic subtypes from chemonaive MPM patients. Diagnostic biopsies of MPM patients from four Italian cancer centers were centrally collected and analyzed. MDM2 and HIF1alpha expression levels were investigated through immunohistochemistry and RT-qPCR. Pathological assessment of necrosis, inflammation and proliferation index was also performed. Molecular markers, pathological features and clinical characteristics were correlated to overall survival (OS) and progression free survival (PFS). Sixty MPM patients were included in the study (32 epithelioid and 28 non-epithelioid). Higher levels of MDM2 (p < 0.001), HIF1alpha (p = 0.013), necrosis (p = 0.013) and proliferation index (p < 0.001) were seen mainly in sarcomatoid/biphasic subtypes. Higher levels of inflammation were significantly associated with epithelioid subtype (p = 0.044). MDM2 expression levels were correlated with HIF1alpha levels (p = 0.0001), necrosis (p = 0.008) and proliferation index (p = 0.009). Univariate analysis showed a significant correlation of non-epithelioid histology (p = 0.04), high levels of necrosis (p = 0.037) and proliferation index (p = 0.0002) with shorter PFS. Sarcomatoid/biphasic and epithelioid mesotheliomas showed different MDM2 and HIF1alpha expression levels and were characterized by different levels of necrosis, proliferation and inflammation. Further studies are warranted to confirm a prognostic and predictive role of such markers and features.
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Affiliation(s)
- Giulia Pasello
- Department of Clinical and Experimental Oncology, Medical Oncology 2, Istituto Oncologico Veneto IRCCS Padova, Italy
| | - Loredana Urso
- Department of Surgery, Oncology and Gastroenterology, University of Padova, Padova, Italy
| | | | - Federica Grosso
- Oncohematologic Department, Mesothelioma Unit, Oncology, SS Antonio e Biagio General Hospital, Alessandria, Italy
| | | | - Francesca Lunardi
- Department of Cardio-Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | - Stefania Edith Vuljan
- Department of Cardio-Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | - Roberta Bertorelle
- Department of Clinical and Experimental Oncology, Immunology and Molecular Oncology Unit, Istituto Oncologico Veneto IRCCS, Padova, Italy
| | - Valeria Sacchetto
- Department of Clinical and Experimental Oncology, Immunology and Molecular Oncology Unit, Istituto Oncologico Veneto IRCCS, Padova, Italy
| | - Vincenzo Ciminale
- Department of Surgery, Oncology and Gastroenterology, University of Padova, Padova, Italy.,Department of Clinical and Experimental Oncology, Immunology and Molecular Oncology Unit, Istituto Oncologico Veneto IRCCS, Padova, Italy
| | - Federico Rea
- Department of Cardio-Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | - Adolfo Favaretto
- Department of Clinical and Experimental Oncology, Medical Oncology 2, Istituto Oncologico Veneto IRCCS Padova, Italy
| | - PierFranco Conte
- Department of Clinical and Experimental Oncology, Medical Oncology 2, Istituto Oncologico Veneto IRCCS Padova, Italy.,Department of Surgery, Oncology and Gastroenterology, University of Padova, Padova, Italy
| | - Fiorella Calabrese
- Department of Cardio-Thoracic and Vascular Sciences, University of Padova, Padova, Italy
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18
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Frum RA, Love IM, Damle PK, Mukhopadhyay ND, Palit Deb S, Deb S, Grossman SR. Constitutive Activation of DNA Damage Checkpoint Signaling Contributes to Mutant p53 Accumulation via Modulation of p53 Ubiquitination. Mol Cancer Res 2016; 14:423-36. [PMID: 26965143 DOI: 10.1158/1541-7786.mcr-15-0363] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 02/23/2016] [Indexed: 02/02/2023]
Abstract
UNLABELLED Many mutant p53 proteins exhibit an abnormally long half-life and overall increased abundance compared with wild-type p53 in tumors, contributing to mutant p53's gain-of-function oncogenic properties. Here, a novel mechanism is revealed for the maintenance of mutant p53 abundance in cancer that is dependent on DNA damage checkpoint activation. High-level mutant p53 expression in lung cancer cells was associated with preferential p53 monoubiquitination versus polyubiquitination, suggesting a role for the ubiquitin/proteasome system in regulation of mutant p53 abundance in cancer cells. Interestingly, mutant p53 ubiquitination status was regulated by ataxia-telangectasia mutated (ATM) activation and downstream phosphorylation of mutant p53 (serine 15), both in resting and in genotoxin-treated lung cancer cells. Specifically, either inhibition of ATM with caffeine or mutation of p53 (serine 15 to alanine) restored MDM2-dependent polyubiquitination of otherwise monoubiquitinated mutant p53. Caffeine treatment rescued MDM2-dependent proteasome degradation of mutant p53 in cells exhibiting active DNA damage signaling, and ATM knockdown phenocopied the caffeine effect. Importantly, in cells analyzed individually by flow cytometry, p53 levels were highest in cells exhibiting the greatest levels of DNA damage response, and interference with DNA damage signaling preferentially decreased the relative percentage of cells in a population with the highest levels of mutant p53. These data demonstrate that active DNA damage signaling contributes to high levels of mutant p53 via modulation of ubiquitin/proteasome activity toward p53. IMPLICATION The ability of DNA damage checkpoint signaling to mediate accumulation of mutant p53 suggests that targeting this signaling pathway may provide therapeutic gain. Mol Cancer Res; 14(5); 423-36. ©2016 AACR.
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Affiliation(s)
- Rebecca A Frum
- Division of Hematology, Oncology, and Palliative Care, Virginia Commonwealth University, Richmond, Virginia
| | - Ian M Love
- Division of Hematology, Oncology, and Palliative Care, Virginia Commonwealth University, Richmond, Virginia
| | - Priyadarshan K Damle
- Division of Hematology, Oncology, and Palliative Care, Virginia Commonwealth University, Richmond, Virginia
| | - Nitai D Mukhopadhyay
- Department of Biostatistics, Virginia Commonwealth University, Richmond, Virginia
| | - Swati Palit Deb
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia. VCU Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia
| | - Sumitra Deb
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia. VCU Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia
| | - Steven R Grossman
- Division of Hematology, Oncology, and Palliative Care, Virginia Commonwealth University, Richmond, Virginia. VCU Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia.
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19
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Wu W, Xu C, Ling X, Fan C, Buckley BP, Chernov MV, Ellis L, Li F, Muñoz IG, Wang X. Targeting RING domains of Mdm2-MdmX E3 complex activates apoptotic arm of the p53 pathway in leukemia/lymphoma cells. Cell Death Dis 2015; 6:e2035. [PMID: 26720344 PMCID: PMC4720891 DOI: 10.1038/cddis.2015.358] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 11/05/2015] [Indexed: 12/18/2022]
Abstract
Reactivation of tumor-suppressor p53 for targeted cancer therapy is an attractive strategy for cancers bearing wild-type (WT) p53. Targeting the Mdm2–p53 interface or MdmX ((MDM4), mouse double minute 4)–p53 interface or both has been a focus in the field. However, targeting the E3 ligase activity of Mdm2–MdmX really interesting new gene (RING)–RING interaction as a novel anticancer strategy has never been explored. In this report, we describe the identification and characterization of small molecule inhibitors targeting Mdm2–MdmX RING–RING interaction as a new class of E3 ligase inhibitors. With a fluorescence resonance energy transfer-based E3 activity assay in high-throughput screening of a chemical library, we identified inhibitors (designated as MMRis (Mdm2–MdmX RING domain inhibitors)) that specifically inhibit Mdm2–MdmX E3 ligase activity toward Mdm2 and p53 substrates. MMRi6 and its analog MMRi64 are capable of disrupting Mdm2–MdmX interactions in vitro and activating p53 in cells. In leukemia cells, MMRi64 potently induces downregulation of Mdm2 and MdmX. In contrast to Nutlin3a, MMRi64 only induces the expression of pro-apoptotic gene PUMA (p53 upregulated modulator of apoptosis) with minimal induction of growth-arresting gene p21. Consequently, MMRi64 selectively induces the apoptotic arm of the p53 pathway in leukemia/lymphoma cells. Owing to the distinct mechanisms of action of MMRi64 and Nutlin3a, their combination synergistically induces p53 and apoptosis. Taken together, this study reveals that Mdm2–MdmX has a critical role in apoptotic response of the p53 pathway and MMRi64 may serve as a new pharmacological tool for p53 studies and a platform for cancer drug development.
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Affiliation(s)
- W Wu
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - C Xu
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - X Ling
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - C Fan
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - B P Buckley
- Department of Stress Biology, Small Molecule Screening Core Facility, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - M V Chernov
- Department of Stress Biology, Small Molecule Screening Core Facility, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - L Ellis
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - F Li
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - I G Muñoz
- Crystallography Unit, Structural Biology and Biocomputing Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid, Spain
| | - X Wang
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
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20
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Carrillo AM, Hicks M, Khabele D, Eischen CM. Pharmacologically Increasing Mdm2 Inhibits DNA Repair and Cooperates with Genotoxic Agents to Kill p53-Inactivated Ovarian Cancer Cells. Mol Cancer Res 2015; 13:1197-205. [PMID: 25964101 DOI: 10.1158/1541-7786.mcr-15-0089] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 05/02/2015] [Indexed: 11/16/2022]
Abstract
UNLABELLED The Mdm2 oncogene is a negative regulator of the p53 tumor suppressor and recently identified inhibitor of DNA break repair. Nutlin-3 is a small-molecule inhibitor of Mdm2-p53 interaction that can induce apoptosis in cancer cells through activation of p53. Although this is a promising therapy for those cancers with wild-type p53, half of all human cancers have inactivated p53. Here, we reveal that a previously unappreciated effect of Nutlin is inhibition of DNA break repair, stemming from its ability to increase Mdm2 protein levels. The Nutlin-induced increase in Mdm2 inhibited DNA double-strand break repair and prolonged DNA damage response signaling independent of p53. Mechanistically, this effect of Nutlin required Mdm2 and acted through Nbs1 of the Mre11-Rad50-Nbs1 DNA repair complex. In ovarian cancer cells, where >90% have inactivated p53, Nutlin combined with the genotoxic agents, cisplatin or etoposide, had a cooperative lethal effect resulting in increased DNA damage and apoptosis. Therefore, these data demonstrate an unexpected consequence of pharmacologically increasing Mdm2 levels that when used in combination with genotoxic agents induces synthetic lethality in ovarian cancer cells, and likely other malignant cell types, that have inactivated p53. IMPLICATIONS Data reveal a therapeutically beneficial effect of pharmacologically increasing Mdm2 levels combined with chemotherapeutic agents for malignancies that have lost functional p53.
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Affiliation(s)
- Alexia M Carrillo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Mellissa Hicks
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Dineo Khabele
- Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Christine M Eischen
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee.
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21
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Abstract
The ubiquitin proteasome pathway is critical in restraining the activities of the p53 tumor suppressor. This review by Pant and Lozano focuses on ubiquitination as a mechanism for regulating p53 stability and function and reviews current findings from in vivo models that evaluate the importance of the ubiquitin proteasome system in regulating p53. The ubiquitin proteasome pathway is critical in restraining the activities of the p53 tumor suppressor. Numerous E3 and E4 ligases regulate p53 levels. Additionally, deubquitinating enzymes that modify p53 directly or indirectly also impact p53 function. When alterations of these proteins result in increased p53 activity, cells arrest in the cell cycle, senesce, or apoptose. On the other hand, alterations that result in decreased p53 levels yield tumor-prone phenotypes. This review focuses on the physiological relevance of these important regulators of p53 and their therapeutic implications.
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Affiliation(s)
- Vinod Pant
- Department of Genetics, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA
| | - Guillermina Lozano
- Department of Genetics, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA
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