1
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Xu M, Deng X, Xiang N, Zhang Z, Yang M, Liu Q. Plk3 Enhances Cisplatin Sensitivity of Nonsmall-Cell Lung Cancer Cells through Inhibition of the PI3K/AKT Pathway via Stabilizing PTEN. ACS OMEGA 2024; 9:8995-9002. [PMID: 38434880 PMCID: PMC10905570 DOI: 10.1021/acsomega.3c07271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/05/2024] [Accepted: 01/26/2024] [Indexed: 03/05/2024]
Abstract
Polo-like kinase 3 (Plk3) is involved in tumor development with a tumor suppressive function. However, the effect of Plk3 on the chemoresistance remains unclear. It has been documented that activation of the PI3K/AKT signaling pathway by PTEN loss significantly enhances chemoresistance in nonsmall-cell lung cancer (NSCLC). This study aims to evaluate the PTEN regulation by Plk3 and identify targets and underlying mechanisms that could be used to relieve chemoresistance. Our results showed that silencing Plk3 reduced PTEN expression and activated PI3K/AKT signaling by dephosphorylating and destabilizing PTEN in NSCLC cells. Reducing Plk3 expression promoted drug resistance to cisplatin (DDP), while overexpressing Plk3 promoted DDP sensitivity. However, these effects were attenuated when MK2206, a PI3K/AKT inhibitor, was applied. In conclusion, upregulation of Plk3 sensitized NSCLC cells toward DDP, which provides a potential target to restore DDP chemoresponse. We provided novel evidence that the PTEN/PI3K/AKT signaling pathway could be regulated by Plk3 through phosphorylation of PTEN and highlighted the critical role of Plk3 in the DDP resistance of NSCLC.
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Affiliation(s)
- Mengshan Xu
- Breast
Tumor Center, Hainan Provincial Tumor Hospital, Haikou 570312, Hainan, China
| | - Xiaoyun Deng
- Department
of Medical Oncology, Hainan Provincial Tumor
Hospital, Haikou 570312, Hainan, China
| | - Nana Xiang
- Department
of Medical Oncology, Luoyang Central Hospital, Luoyang 471001, Henan, China
| | - Zhao Zhang
- Breast
Tumor Center, Hainan Provincial Tumor Hospital, Haikou 570312, Hainan, China
| | - Min Yang
- Department
of Medical Oncology, Hainan Provincial Tumor
Hospital, Haikou 570312, Hainan, China
| | - Qinxiang Liu
- Department
of Medical Oncology, Hainan Provincial Tumor
Hospital, Haikou 570312, Hainan, China
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2
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Li Y, Zhu J, Yu Z, Zhai F, Li H, Jin X. Regulation of apoptosis by ubiquitination in liver cancer. Am J Cancer Res 2023; 13:4832-4871. [PMID: 37970337 PMCID: PMC10636691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/04/2023] [Indexed: 11/17/2023] Open
Abstract
Apoptosis is a programmed cell death process critical to cell development and tissue homeostasis in multicellular organisms. Defective apoptosis is a crucial step in the malignant transformation of cells, including hepatocellular carcinoma (HCC), where the apoptosis rate is higher than in normal liver tissues. Ubiquitination, a post-translational modification process, plays a precise role in regulating the formation and function of different death-signaling complexes, including those involved in apoptosis. Aberrant expression of E3 ubiquitin ligases (E3s) in liver cancer (LC), such as cellular inhibitors of apoptosis proteins (cIAPs), X chromosome-linked IAP (XIAP), and linear ubiquitin chain assembly complex (LUBAC), can contribute to HCC development by promoting cell survival and inhibiting apoptosis. Therefore, the review introduces the main apoptosis pathways and the regulation of proteins in these pathways by E3s and deubiquitinating enzymes (DUBs). It summarizes the abnormal expression of these regulators in HCC and their effects on cancer inhibition or promotion. Understanding the role of ubiquitination in apoptosis and LC can provide insights into potential targets for therapeutic intervention.
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Affiliation(s)
- Yuxuan Li
- Department of Hepatobiliary and Pancreatic Surgery, Ningbo Medical Center of LiHuiLi Hospital, Ningbo UniversityNingbo 315040, Zhejiang, P. R. China
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo UniversityNingbo 315211, Zhejiang, P. R. China
| | - Jie Zhu
- Department of Hepatobiliary and Pancreatic Surgery, Ningbo Medical Center of LiHuiLi Hospital, Ningbo UniversityNingbo 315040, Zhejiang, P. R. China
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo UniversityNingbo 315211, Zhejiang, P. R. China
| | - Zongdong Yu
- Department of Hepatobiliary and Pancreatic Surgery, Ningbo Medical Center of LiHuiLi Hospital, Ningbo UniversityNingbo 315040, Zhejiang, P. R. China
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo UniversityNingbo 315211, Zhejiang, P. R. China
| | - Fengguang Zhai
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo UniversityNingbo 315211, Zhejiang, P. R. China
| | - Hong Li
- Department of Hepatobiliary and Pancreatic Surgery, Ningbo Medical Center of LiHuiLi Hospital, Ningbo UniversityNingbo 315040, Zhejiang, P. R. China
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo UniversityNingbo 315211, Zhejiang, P. R. China
| | - Xiaofeng Jin
- Department of Hepatobiliary and Pancreatic Surgery, Ningbo Medical Center of LiHuiLi Hospital, Ningbo UniversityNingbo 315040, Zhejiang, P. R. China
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo UniversityNingbo 315211, Zhejiang, P. R. China
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3
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Sharma P, Mohanty S, Ahmad Y. A study of survival strategies for improving acclimatization of lowlanders at high-altitude. Heliyon 2023; 9:e14929. [PMID: 37025911 PMCID: PMC10070159 DOI: 10.1016/j.heliyon.2023.e14929] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 03/14/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023] Open
Abstract
Human Acclimatization and therapeutic approaches are the core components for conquering the physiological variations at high altitude (≥2500 m) exposure. The declined atmospheric pressure and reduced partial pressure of oxygen at high altitudes tend to decrease the temperature by several folds. Hypobaric hypoxia is a major threat to humanity at high altitudes, and its potential effects include altitude mountain sickness. On severity, it may lead to the development of conditions like high-altitude cerebral edema (HACE) or high-altitude pulmonary edema (HAPE) and cause unexpected physiological changes in the healthy population of travelers, athletes, soldiers, and low landers while sojourning at high altitude. Previous investigations have been done on long-drawn-out acclimatization strategies such as the staging method to prevent the damage caused by high-altitude hypobaric Hypoxia. Inherent Limitations of this strategy hamper the daily lifestyle and time consuming for people. It is not suitable for the rapid mobilization of people at high altitudes. There is a need to recalibrate acclimatization strategies for improving health protection and adapting to the environmental variations at high altitudes. This narrative review details the geographical changes and physiological changes at high altitudes and presents a framework of acclimatization, pre-acclimatization, and pharmacological aspects of high-altitude survival to enhance the government efficacy and capacity for the strategic planning of acclimatization, use of therapeutics, and safe de-induction from high altitude for minimizing the life loss. It's simply too ambitious for the importance of the present review to reduce life loss, and it can be proved as the most essential aspect of the preparatory phase of high-altitude acclimatization in plateau regions without hampering the daily lifestyle. The application of pre-acclimatization techniques can be a boon for people serving at high altitudes, and it can be a short bridge for the rapid translocation of people at high altitudes by minimizing the acclimatization time.
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Affiliation(s)
- Poornima Sharma
- Defence Institute of Physiology & Allied Sciences (DIPAS), Defence R&D Organization (DRDO), Timarpur, New Delhi, 110054, India
| | - Swaraj Mohanty
- Defence Institute of Physiology & Allied Sciences (DIPAS), Defence R&D Organization (DRDO), Timarpur, New Delhi, 110054, India
| | - Yasmin Ahmad
- Defence Institute of Physiology & Allied Sciences (DIPAS), Defence R&D Organization (DRDO), Timarpur, New Delhi, 110054, India
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4
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Kotzampasi DM, Premeti K, Papafotika A, Syropoulou V, Christoforidis S, Cournia Z, Leondaritis G. The orchestrated signaling by PI3Kα and PTEN at the membrane interface. Comput Struct Biotechnol J 2022; 20:5607-5621. [PMID: 36284707 PMCID: PMC9578963 DOI: 10.1016/j.csbj.2022.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/03/2022] [Accepted: 10/03/2022] [Indexed: 11/16/2022] Open
Abstract
The oncogene PI3Kα and the tumor suppressor PTEN represent two antagonistic enzymatic activities that regulate the interconversion of the phosphoinositide lipids PI(4,5)P2 and PI(3,4,5)P3 in membranes. As such, they are defining components of phosphoinositide-based cellular signaling and membrane trafficking pathways that regulate cell survival, growth, and proliferation, and are often deregulated in cancer. In this review, we highlight aspects of PI3Kα and PTEN interplay at the intersection of signaling and membrane trafficking. We also discuss the mechanisms of PI3Kα- and PTEN- membrane interaction and catalytic activation, which are fundamental for our understanding of the structural and allosteric implications on signaling at the membrane interface and may aid current efforts in pharmacological targeting of these proteins.
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Affiliation(s)
- Danai Maria Kotzampasi
- Biomedical Research Foundation, Academy of Athens, Athens 11527, Greece
- Department of Biology, University of Crete, Heraklion 71500, Greece
| | - Kyriaki Premeti
- Laboratory of Pharmacology, Faculty of Medicine, University of Ioannina, Ioannina 45110, Greece
| | - Alexandra Papafotika
- Laboratory of Biological Chemistry, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina 45110, Greece
- Biomedical Research Institute, Foundation for Research and Technology, Ioannina 45110, Greece
| | - Vasiliki Syropoulou
- Laboratory of Pharmacology, Faculty of Medicine, University of Ioannina, Ioannina 45110, Greece
| | - Savvas Christoforidis
- Laboratory of Biological Chemistry, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina 45110, Greece
- Biomedical Research Institute, Foundation for Research and Technology, Ioannina 45110, Greece
| | - Zoe Cournia
- Biomedical Research Foundation, Academy of Athens, Athens 11527, Greece
| | - George Leondaritis
- Laboratory of Pharmacology, Faculty of Medicine, University of Ioannina, Ioannina 45110, Greece
- Institute of Biosciences, University Research Center of Ioannina, Ioannina 45110, Greece
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5
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Ledderose JMT, Benitez JA, Roberts AJ, Reed R, Bintig W, Larkum ME, Sachdev RNS, Furnari F, Eickholt BJ. The impact of phosphorylated PTEN at threonine 366 on cortical connectivity and behaviour. Brain 2022; 145:3608-3621. [PMID: 35603900 DOI: 10.1093/brain/awac188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 04/19/2022] [Accepted: 05/04/2022] [Indexed: 11/14/2022] Open
Abstract
The lipid phosphatase PTEN (phosphatase and tensin homologue on chromosome 10) is a key tumour suppressor gene and an important regulator of neuronal signalling. PTEN mutations have been identified in patients with autism spectrum disorders, characterized by macrocephaly, impaired social interactions and communication, repetitive behaviour, intellectual disability, and epilepsy. PTEN enzymatic activity is regulated by a cluster of phosphorylation sites at the C-terminus of the protein. Here, we focussed on the role of PTEN T366 phosphorylation and generated a knock-in mouse line in which Pten T366 was substituted with alanine (PtenT366A/T366A). We identify that phosphorylation of PTEN at T366 controls neuron size and connectivity of brain circuits involved in sensory processing. We show in behavioural tests that PtenT366/T366A mice exhibit cognitive deficits and selective sensory impairments, with significant differences in male individuals. We identify restricted cellular overgrowth of cortical neurons in PtenT366A/T366A brains, linked to increases in both dendritic arborization and soma size. In a combinatorial approach of anterograde and retrograde monosynaptic tracing using rabies virus, we characterize differences in connectivity to the primary somatosensory cortex of PtenT366A/T366A brains, with imbalances in long-range cortico-cortical input to neurons. We conclude that phosphorylation of PTEN at T366 controls neuron size and connectivity of brain circuits involved in sensory processing and propose that PTEN T366 signalling may account for a subset of autism-related functions of PTEN.
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Affiliation(s)
- Julia M T Ledderose
- Institute for Biochemistry, Charité Universitätsmedizin Berlin, Germany.,Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jorge A Benitez
- Bristol Myers Squibb, 10300 Campus Point Drive, Suite 100, San Diego, California, 92121, USA
| | - Amanda J Roberts
- The Scripps Research Institute, Animal Models Core, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
| | - Rachel Reed
- Bristol Myers Squibb, 10300 Campus Point Drive, Suite 100, San Diego, California, 92121, USA
| | - Willem Bintig
- Institute for Biochemistry, Charité Universitätsmedizin Berlin, Germany
| | - Matthew E Larkum
- Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany.,Neurocure Center for Excellence, Charité Universitätsmedizin Berlin, Germany
| | | | - Frank Furnari
- Ludwig Cancer Institute, San Diego, USA.,University of California San Diego, La Jolla, USA
| | - Britta J Eickholt
- Institute for Biochemistry, Charité Universitätsmedizin Berlin, Germany.,Neurocure Center for Excellence, Charité Universitätsmedizin Berlin, Germany
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6
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Wang K, Liu J, Li YL, Li JP, Zhang R. Ubiquitination/de-ubiquitination: A promising therapeutic target for PTEN reactivation in cancer. Biochim Biophys Acta Rev Cancer 2022; 1877:188723. [DOI: 10.1016/j.bbcan.2022.188723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/01/2022] [Accepted: 03/15/2022] [Indexed: 02/07/2023]
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7
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Korns J, Liu X, Takiar V. A review of Plks: Thinking outside the (polo) box. Mol Carcinog 2022; 61:254-263. [PMID: 35049091 DOI: 10.1002/mc.23388] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/07/2021] [Accepted: 12/07/2021] [Indexed: 12/19/2022]
Abstract
The polo-like kinase (Plk) family is comprised of five different members (Plk1-5), each with their own distinct functions. Plk family members participate in pivotal cell division processes as well as in non-mitotic roles. Importantly, Plk expression has been correlated with various disease states, including cancer. Multiples therapies, which primarily target Plk1, are currently being investigated alone or in combination with other agents for clinical use in different cancers. As the role of Plks in disease progression becomes more prominent, it is important to outline their functions as cell cycle regulators and more. This review summarizes the structure and both mitotic and non-mitotic functions of each of the five Plk family members, sequentially. Additionally, the proposed mechanisms for how Plks contribute to tumorigenesis and the therapeutics currently under investigation are outlined.
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Affiliation(s)
- Julianna Korns
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnat, Ohio, USA
| | - Xiaoqi Liu
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Vinita Takiar
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnat, Ohio, USA.,Cincinnati VA Medical Center, Cincinnati, Ohio, USA
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8
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Craig SN, Baxter M, Chapagai D, Stafford JM, Nurmemmedov E, Altomare D, Wyatt MD, McInnes C. Structure-activity and mechanistic studies of non-peptidic inhibitors of the PLK1 polo box domain identified through REPLACE. Eur J Med Chem 2022; 227:113926. [PMID: 34735919 PMCID: PMC9137042 DOI: 10.1016/j.ejmech.2021.113926] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 10/06/2021] [Accepted: 10/13/2021] [Indexed: 01/07/2023]
Abstract
Polo-like kinase 1 (PLK1) is a serine/threonine-protein kinase involved in cell cycle regulation and mitotic progression. Studies have shown that PLK1 is upregulated in many tumors and high levels are adversely related to a poor prognosis. Knocking down or inhibiting PLK1 results in synthetic lethality in PTEN deficient prostate tumors and Kras mutant colorectal tumors, further validating PLK1 as an oncotarget. Substrate recognition by PLK1 occurs through the Polo-Box Domain (PBD), which is a phospho-peptide binding site also responsible for subcellular localization. Much effort has been directed to target this kinase therapeutically through the ATP-binding site, and a few such inhibitors have advanced to clinical trials however with limited clinical efficacy. Moreover, it has been shown that a point mutation in PLK1 (C67V) confers dramatic cellular resistance to catalytic site inhibitors. An alternative approach to target PLK1 potently and selectively is through the PBD to block its protein-protein interactions. Through the REPLACE strategy, for converting peptide inhibitors into more drug-like non peptidic compounds, a PBD targeting compound series ("ABBAs"), has been identified and the key determinants of potency and selectivity elucidated through structure-activity relationship studies. In cellular experiments, the ABBAs were shown to lead to profound effects on the cell cycle, to inhibit tumor proliferation and overcome resistance of cells expressing the PLK1 C67V mutant to ATP-based inhibitors. These non-ATP competitive inhibitors of PLK1 were also used chemical biology probes to investigate the gene regulatory effects of PLK1, known to act on transcription factors such as p53.
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Affiliation(s)
- Sandra N Craig
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA.
| | - Merissa Baxter
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA.
| | - Danda Chapagai
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA
| | - Jessy M Stafford
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA
| | - Elmar Nurmemmedov
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA
| | - Diego Altomare
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA
| | - Michael D Wyatt
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA
| | - Campbell McInnes
- Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, 29208, USA.
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9
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Lupinacci S, Perri A, Toteda G, Vizza D, Lofaro D, Pontrelli P, Stallone G, Divella C, Tessari G, La Russa A, Zaza G, Bonofiglio R. Rapamycin promotes autophagy cell death of Kaposi's sarcoma cells through P75NTR activation. Exp Dermatol 2021; 31:143-153. [PMID: 34331820 DOI: 10.1111/exd.14438] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 05/10/2021] [Accepted: 07/22/2021] [Indexed: 12/27/2022]
Abstract
The mammalian target of rapamycin inhibitor (mTOR-I) Rapamycin, a drug widely used in kidney transplantation, exerts important anti-cancer effects, particularly in Kaposi's Sarcoma (KS), through several biological interactions. In this in vivo and in vitro study, we explored whether the activation of the autophagic pathway through the low-affinity receptor for nerve growth factor, p75NTR , may have a pivotal role in the anti-cancer effect exerted by Rapamycin in S. Our Kimmunohistochemistry results revealed a significant hyper-activation of the autophagic pathway in KS lesions. In vitro experiments on KS cell lines showed that Rapamycin exposure reduced cell viability by increasing the autophagic process, in the absence of apoptosis, through the transcriptional activation of p75NTR via EGR1. Interestingly, p75NTR gene silencing prevented the increase of the autophagic process and the reduction of cell viability. Moreover, p75NTR activation promoted the upregulation of phosphatase and tensin homolog (PTEN), a tumour suppressor that modulates the PI3K/Akt/mTOR pathway. In conclusion, our in vitro data demonstrated, for the first time, that in Kaposi's sarcoma, autophagy triggered by Rapamycin through p75NTR represented a major mechanism by which mTOR inhibitors may induce tumour regression. Additionally, it suggested that p75NTR protein analysis could be proposed as a new potential biomarker to predict response to Rapamycin in kidney transplant recipients affected by Kaposi's sarcoma.
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Affiliation(s)
- Simona Lupinacci
- Department of Nephrology, Dialysis and Transplantation, "Kidney and Transplantation" Research Centre, Annunziata Hospital, Cosenza, Italy
| | - Anna Perri
- Department of Nephrology, Dialysis and Transplantation, "Kidney and Transplantation" Research Centre, Annunziata Hospital, Cosenza, Italy
| | - Giuseppina Toteda
- Department of Nephrology, Dialysis and Transplantation, "Kidney and Transplantation" Research Centre, Annunziata Hospital, Cosenza, Italy
| | - Donatella Vizza
- Department of Nephrology, Dialysis and Transplantation, "Kidney and Transplantation" Research Centre, Annunziata Hospital, Cosenza, Italy
| | - Danilo Lofaro
- Department of Nephrology, Dialysis and Transplantation, "Kidney and Transplantation" Research Centre, Annunziata Hospital, Cosenza, Italy
| | - Paola Pontrelli
- Nephrology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Giovanni Stallone
- Nephrology Dialysis and Transplantation Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Chiara Divella
- Nephrology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Gianpaolo Tessari
- Section of Dermatology and Venereology, University-Hospital of Verona, Verona, Italy
| | - Antonella La Russa
- Department of Nephrology, Dialysis and Transplantation, "Kidney and Transplantation" Research Centre, Annunziata Hospital, Cosenza, Italy
| | - Gianluigi Zaza
- Renal Unit, Department of Medicine, University-Hospital of Verona, Verona, Italy
| | - Renzo Bonofiglio
- Department of Nephrology, Dialysis and Transplantation, "Kidney and Transplantation" Research Centre, Annunziata Hospital, Cosenza, Italy
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10
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Raab CA, Raab M, Becker S, Strebhardt K. Non-mitotic functions of polo-like kinases in cancer cells. Biochim Biophys Acta Rev Cancer 2021; 1875:188467. [PMID: 33171265 DOI: 10.1016/j.bbcan.2020.188467] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/03/2020] [Accepted: 11/03/2020] [Indexed: 12/12/2022]
Abstract
Inhibitors of mitotic protein kinases are currently being developed as non-neurotoxic alternatives of microtubule-targeting agents (taxanes, vinca alkaloids) which provide a substantial survival benefit for patients afflicted with different types of solid tumors. Among the mitotic kinases, the cyclin-dependent kinases, the Aurora kinases, the kinesin spindle protein and Polo-like kinases (PLKs) have emerged as attractive targets of cancer therapeutics. The functions of mammalian PLK1-5 are traditionally linked to the regulation of the cell cycle and to the stress response. Especially the key role of PLK1 and PLK4 in cellular growth and proliferation, their overexpression in multiple types of human cancer and their druggability, make them appealing targets for cancer therapy. Inhibitors for PLK1 and PLK4 are currently being tested in multiple cancer trials. The clinical success of microtubule-targeting agents is attributed not solely to the induction of a mitotic arrest in cancer cells, but also to non-mitotic effects like targeting intracellular trafficking on microtubules. This raises the question whether new cancer targets like PLK1 and PLK4 regulate critical non-mitotic functions in tumor cells. In this article we summarize the important roles of PLK1-5 for the regulation of non-mitotic signaling. Due to these functions it is conceivable that inhibitors for PLK1 or PLK4 can target interphase cells, which underscores their attractive potential as cancer drug targets. Moreover, we also describe the contribution of the tumor-suppressors PLK2, PLK3 and PLK5 to cancer cell signaling outside of mitosis. These observations highlight the urgent need to develop highly specific ATP-competitive inhibitors for PLK4 and for PLK1 like the 3rd generation PLK-inhibitor Onvansertib to prevent the inhibition of tumor-suppressor PLKs in- and outside of mitosis. The remarkable feature of PLKs to encompass a unique druggable domain, the polo-box-domain (PBD) that can be found only in PLKs offers the opportunity for the development of inhibitors that target PLKs exclusively. Beyond the development of mono-specific ATP-competitive PLK inhibitors, the PBD as drug target will support the design of new drugs that eradicate cancer cells based on the mitotic and non-mitotic function of PLK1 and PLK4.
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Affiliation(s)
| | - Monika Raab
- Department of Gynecology, Goethe-University, Frankfurt, Germany
| | - Sven Becker
- Department of Gynecology, Goethe-University, Frankfurt, Germany
| | - Klaus Strebhardt
- Department of Gynecology, Goethe-University, Frankfurt, Germany; German Cancer Consortium (DKTK), German Cancer Research Center, Partner Site Frankfurt am Main, Frankfurt, Germany.
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11
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Albanese A, Daly LA, Mennerich D, Kietzmann T, Sée V. The Role of Hypoxia-Inducible Factor Post-Translational Modifications in Regulating Its Localisation, Stability, and Activity. Int J Mol Sci 2020; 22:E268. [PMID: 33383924 PMCID: PMC7796330 DOI: 10.3390/ijms22010268] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 12/12/2022] Open
Abstract
The hypoxia signalling pathway enables adaptation of cells to decreased oxygen availability. When oxygen becomes limiting, the central transcription factors of the pathway, hypoxia-inducible factors (HIFs), are stabilised and activated to induce the expression of hypoxia-regulated genes, thereby maintaining cellular homeostasis. Whilst hydroxylation has been thoroughly described as the major and canonical modification of the HIF-α subunits, regulating both HIF stability and activity, a range of other post-translational modifications decorating the entire protein play also a crucial role in altering HIF localisation, stability, and activity. These modifications, their conservation throughout evolution, and their effects on HIF-dependent signalling are discussed in this review.
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Affiliation(s)
- Adam Albanese
- Department of Molecular Physiology and Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L697ZB, UK;
| | - Leonard A. Daly
- Department of Biochemistry and System Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L697ZB, UK;
| | - Daniela Mennerich
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, FI-90014 Oulu, Finland; (D.M.); (T.K.)
| | - Thomas Kietzmann
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, FI-90014 Oulu, Finland; (D.M.); (T.K.)
| | - Violaine Sée
- Department of Molecular Physiology and Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L697ZB, UK;
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12
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Nussinov R, Zhang M, Tsai CJ, Jang H. Phosphorylation and Driver Mutations in PI3Kα and PTEN Autoinhibition. Mol Cancer Res 2020; 19:543-548. [PMID: 33288731 DOI: 10.1158/1541-7786.mcr-20-0818] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/29/2020] [Accepted: 12/03/2020] [Indexed: 11/16/2022]
Abstract
PI3K and PTEN are the second and third most highly mutated proteins in cancer following only p53. Their actions oppose each other. PI3K phosphorylates signaling lipid PIP2 to PIP3 PTEN dephosphorylates it back. Driver mutations in both proteins accrue PIP3 PIP3 recruits AKT and PDK1 to the membrane, promoting cell-cycle progression. Here we review phosphorylation events and mutations in autoinhibition in PI3K and PTEN from the structural standpoint. Our purpose is to clarify how they control the autoinhibited states. In autoinhibition, a segment or a subunit of the protein occludes its functional site. Protein-protein interfaces are often only marginally stable, making them sensitive to changes in conditions in living cells. Phosphorylation can stabilize or destabilize the interfaces. Driver mutations commonly destabilize them. In analogy to "passenger mutations," we coin "passenger phosphorylation" to emphasize that the presence of a phosphorylation recognition sequence logo does not necessarily imply function. Rather, it may simply reflect a statistical occurrence. In both PI3K and PTEN, autoinhibiting phosphorylation events are observed in the occluding "piece." In PI3Kα, the "piece" is the p85α subunit. In PTEN, it is the C-terminal segment. In both enzymes the stabilized interface covers the domain that attaches to the membrane. Driver mutations that trigger rotation of the occluding piece or its deletion prompt activation. To date, both enzymes lack specific, potent drugs. We discuss the implications of detailed structural and mechanistic insight into oncogenic activation and how it can advance allosteric precision oncology.
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Affiliation(s)
- Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, NCI, Frederick, Maryland. .,Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Mingzhen Zhang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, NCI, Frederick, Maryland
| | - Chung-Jung Tsai
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, NCI, Frederick, Maryland
| | - Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, NCI, Frederick, Maryland
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13
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Baxter M, Chapagai D, Craig S, Hurtado C, Varghese J, Nurmemmedov E, Wyatt MD, McInnes C. Peptidomimetic Polo-Box-Targeted Inhibitors that Engage PLK1 in Tumor Cells and Are Selective against the PLK3 Tumor Suppressor. ChemMedChem 2020; 15:1058-1066. [PMID: 32232973 PMCID: PMC7703809 DOI: 10.1002/cmdc.202000137] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Indexed: 12/26/2022]
Abstract
The polo-box domain (PBD) of PLK1 determines mitotic substrate recognition and subcellular localization. Compounds that target PLK1 selectively are required due to the tumor-suppressor roles of PLK3. A structure-activity analysis of the PBD phosphopeptide binding motif has identified potent peptides that delineate the determinants required for mimicry by nonpeptidic inhibitors and provide insights into the structural basis for the selectivity of inhibitors for the PLK1 PBD. Fragment-ligated inhibitory peptides (FLIPs) obtained through REPLACE have been optimized to enhance in vitro binding and a systematic analysis of selectivity for PLK1 vs PLK3 has been carried out for peptides and peptidomimetics. Furthermore, these more drug-like non-ATP-competitive inhibitors had on-target engagement in a cellular context, as evidenced by stabilization of PLK1 in a thermal-shift assay and by inhibition of the phosphorylation of TCTP, a target of PLK1. Investigation in cells expressing a mutant PLK1 showed that these cells are sensitive to PBD inhibitors but dramatically resistant to clinically investigated ATP-competitive compounds. These results further validate targeting the PBD binding site in the move towards PLK1 inhibitors that are active against tumors resistant to ATP inhibitors.
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Affiliation(s)
- Merissa Baxter
- Drug Discovery and Biomedical Sciences College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
- Present Address: NCI Shady Grove, Rockville, MD 20850-9702, USA
| | - Danda Chapagai
- Drug Discovery and Biomedical Sciences College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
| | - Sandra Craig
- Drug Discovery and Biomedical Sciences College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
- Present Address: Department of Chemistry, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Cecilia Hurtado
- Drug Discovery and Biomedical Sciences College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
- Present Address: University of California San Francisco, San Francisco, CA 94115, USA
| | - Jessy Varghese
- Drug Discovery and Biomedical Sciences College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
| | - Elmar Nurmemmedov
- John Wayne Cancer Institute and Pacific Neuroscience Institute Providence Saint John's Health Center, Santa Monica, CA, USA
| | - Michael D Wyatt
- Drug Discovery and Biomedical Sciences College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
| | - Campbell McInnes
- Drug Discovery and Biomedical Sciences College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
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14
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Ho J, Cruise ES, Dowling RJO, Stambolic V. PTEN Nuclear Functions. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a036079. [PMID: 31712221 DOI: 10.1101/cshperspect.a036079] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
For years, clinical and basic researchers have been aware of the presence of PTEN in the nucleus in cell culture, animal models, and both healthy and diseased human tissues. Despite the early recognition of nuclear PTEN, the understanding of the mechanisms of its nuclear localization, function in the nucleus, and importance in biology and human disease has been lacking. Over the last decade, emerging concepts for the complex involvement of nuclear PTEN in a variety of processes, including genome maintenance and DNA repair, cell-cycle control, gene expression, and DNA replication, are illuminating what could prove to be the key path toward a full understanding of PTEN function in health and disease. Dysregulation of nuclear PTEN is now considered an important aspect of the etiology of many pathologic conditions, prompting reconsideration of the therapeutic approaches aimed at countering the consequences of PTEN deficiency. This new knowledge is fueling the development of innovative therapeutic modalities for a broad spectrum of human conditions, from cancer and metabolic diseases, to neurological disorders and autism.
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Affiliation(s)
- Jason Ho
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Edward S Cruise
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Ryan J O Dowling
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Vuk Stambolic
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
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Abstract
The tumor suppressor phosphatase and tensin homolog on chromosome 10 (PTEN) is a tightly regulated enzyme responsible for dephosphorylating the progrowth lipid messenger molecule phosphatidylinositol 3,4,5-trisphosphate (PIP3) on the plasma membrane. The carboxy-terminal tail (CTT) of PTEN is key for regulation of the enzyme. When phosphorylated, the unstructured CTT interacts with the phosphatase-C2 superdomain to inactivate the enzyme by preventing membrane association. PTEN mutations associated with cancer also inactivate the enzyme. Alternate translation-initiation sites generate extended isoforms of PTEN, such as PTEN-L that has multiple roles in cells. The extended amino-terminal region bears a signal sequence and a polyarginine sequence to facilitate exit from and entry into cells, respectively, and a membrane-binding helix that activates the enzyme. This amino-terminal region also facilitates mitochondrial and nucleolar localization. This review explores PTEN structure and its impact on localization and regulation.
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16
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Ou B, Sun H, Zhao J, Xu Z, Liu Y, Feng H, Peng Z. Polo-like kinase 3 inhibits glucose metabolism in colorectal cancer by targeting HSP90/STAT3/HK2 signaling. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2019; 38:426. [PMID: 31655629 PMCID: PMC6815449 DOI: 10.1186/s13046-019-1418-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 09/09/2019] [Indexed: 01/06/2023]
Abstract
Background Polo-like kinase 3 (PLK3) has been documented as a tumor suppressor in several types of malignancies. However, the role of PLK3 in colorectal cancer (CRC) progression and glucose metabolism remains to be known. Methods The expression of PLK3 in CRC tissues was determined by immunohistochemistry. Cells proliferation was examined by EdU, CCK-8 and in vivo analyses. Glucose metabolism was assessed by detecting lactate production, glucose uptake, mitochondrial respiration, extracellular acidification rate, oxygen consumption rate and ATP production. Chromatin immunoprecipitation, luciferase reporter assays and co-immunoprecipitation were performed to explore the signaling pathway. Specific targeting by miRNAs was determined by luciferase reporter assays and correlation with target protein expression. Results PLK3 was significantly downregulated in CRC tissues and its low expression was correlated with worse prognosis of patients. In vitro and in vivo experiments revealed that PLK3 contributed to growth inhibition of CRC cells. Furthermore, we demonstrated that PLK3 impeded glucose metabolism via targeting Hexokinase 2 (HK2) expression. Mechanically, PLK3 bound to Heat shock protein 90 (HSP90) and facilitated its degradation, which led to a significant decrease of phosphorylated STAT3. The downregulation of p-STAT3 further suppressed the transcriptional activation of HK2. Moreover, our investigations showed that PLK3 was directly targeted by miR-106b at post-transcriptional level in CRC cells. Conclusion This study suggests that PLK3 inhibits glucose metabolism by targeting HSP90/STAT3/HK2 signaling and PLK3 may serve as a potential therapeutic target in colorectal cancer.
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Affiliation(s)
- Baochi Ou
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, No. 100, Haining Road, Shanghai, 200080, China
| | - Hongze Sun
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, No. 100, Haining Road, Shanghai, 200080, China
| | - Jingkun Zhao
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhuoqing Xu
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yuan Liu
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, No. 100, Haining Road, Shanghai, 200080, China
| | - Hao Feng
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhihai Peng
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, No. 100, Haining Road, Shanghai, 200080, China.
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17
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An SWA, Choi E, Hwang W, Son HG, Yang J, Seo K, Nam H, Nguyen NTH, Kim EJE, Suh BK, Kim Y, Nakano S, Ryu Y, Man Ha C, Mori I, Park SK, Yoo J, Kim S, Lee SV. KIN-4/MAST kinase promotes PTEN-mediated longevity of Caenorhabditis elegans via binding through a PDZ domain. Aging Cell 2019; 18:e12906. [PMID: 30773781 PMCID: PMC6516182 DOI: 10.1111/acel.12906] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/16/2018] [Accepted: 12/02/2018] [Indexed: 01/09/2023] Open
Abstract
PDZ domain‐containing proteins (PDZ proteins) act as scaffolds for protein–protein interactions and are crucial for a variety of signal transduction processes. However, the role of PDZ proteins in organismal lifespan and aging remains poorly understood. Here, we demonstrate that KIN‐4, a PDZ domain‐containing microtubule‐associated serine‐threonine (MAST) protein kinase, is a key longevity factor acting through binding PTEN phosphatase in Caenorhabditis elegans. Through a targeted genetic screen for PDZ proteins, we find that kin‐4 is required for the long lifespan of daf‐2/insulin/IGF‐1 receptor mutants. We then show that neurons are crucial tissues for the longevity‐promoting role of kin‐4. We find that the PDZ domain of KIN‐4 binds PTEN, a key factor for the longevity of daf‐2 mutants. Moreover, the interaction between KIN‐4 and PTEN is essential for the extended lifespan of daf‐2 mutants. As many aspects of lifespan regulation in C. elegans are evolutionarily conserved, MAST family kinases may regulate aging and/or age‐related diseases in mammals through their interaction with PTEN.
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Affiliation(s)
- Seon Woo A. An
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Eun‐Seok Choi
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Wooseon Hwang
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Heehwa G. Son
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Jae‐Seong Yang
- School of Interdisciplinary Bioscience and Bioengineering Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Keunhee Seo
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Hyun‐Jun Nam
- School of Interdisciplinary Bioscience and Bioengineering Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Nhung T. H. Nguyen
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Eun Ji E. Kim
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Bo Kyoung Suh
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Youngran Kim
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Shunji Nakano
- Neuroscience Institute, Graduate School of Science Nagoya University Nagoya Japan
| | - Youngjae Ryu
- Research Division Korea Brain Research Institute Daegu South Korea
| | - Chang Man Ha
- Research Division Korea Brain Research Institute Daegu South Korea
| | - Ikue Mori
- Neuroscience Institute, Graduate School of Science Nagoya University Nagoya Japan
| | - Sang Ki Park
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Joo‐Yeon Yoo
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Sanguk Kim
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
- School of Interdisciplinary Bioscience and Bioengineering Pohang University of Science and Technology Pohang Gyeongbuk South Korea
| | - Seung‐Jae V. Lee
- Department of Life Sciences Pohang University of Science and Technology Pohang Gyeongbuk South Korea
- School of Interdisciplinary Bioscience and Bioengineering Pohang University of Science and Technology Pohang Gyeongbuk South Korea
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18
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Tsai CY, Dai KY, Fang C, Wu JCC, Chan SHH. PTEN/FLJ10540/PI3K/Akt cascade in experimental brain stem death: A newfound role for a classical tumorigenic signaling pathway. Biochem Pharmacol 2018; 155:207-212. [PMID: 30008438 DOI: 10.1016/j.bcp.2018.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 07/01/2018] [Indexed: 12/28/2022]
Abstract
Despite great advances in contemporary medicine, brain death still remains enigmatic and its cellular and molecular mechanisms unsettled. This review summarizes recent findings that substantiate the notion that PTEN/FLJ10540/PI3K/Akt cascade, the classical tumorigenic signaling pathway, is actively engaged in experimental brain stem death. These results were based on a clinically relevant animal model that employs the pesticide mevinphos as the experimental insult in Sprague-Dawley rats to mimic brain stem death in patients died of organophosphate poisoning. The neural substrate investigated is the rostral ventrolateral medulla (RVLM), a brain stem site classically known to maintain arterial pressure (AP) and is established to be the origin of a "life-and-death" signal detected from AP, which reflects brain stem cardiovascular dysregulation that precedes death. Activation of PI3K/Akt signaling pathway in the RVLM upregulates the nuclear factor-κB/nitric oxide synthase II/peroxynitrite cascade, resulting in impairment of brain stem cardiovascular regulation that leads to the loss of the "life-and-death" signal in experimental brain stem death. This process is reinforced by FLJ10540, a PI3K-association protein; and is counteracted by PTEN, a negative regulator of PI3K/Akt signaling. The concept that a classical signaling pathway in tumorigenesis is also an active player in cardiovascular dysregulation in brain stem death provides new ramifications for translational medicine. It promulgates the concept that rather than focusing on a particular disease condition, a new vista for future therapeutic strategy against both fatal eventualities should target at this common cellular cascade.
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Affiliation(s)
- Ching-Yi Tsai
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan, Republic of China.
| | - Kuang-Yu Dai
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan, Republic of China
| | - Chi Fang
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan, Republic of China
| | - Jacqueline C C Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan, Republic of China
| | - Samuel H H Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan, Republic of China.
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19
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Yang C, Huang X, Liu H, Xiao F, Wei J, You L, Qian W. PDK1 inhibitor GSK2334470 exerts antitumor activity in multiple myeloma and forms a novel multitargeted combination with dual mTORC1/C2 inhibitor PP242. Oncotarget 2018; 8:39185-39197. [PMID: 28402933 PMCID: PMC5503605 DOI: 10.18632/oncotarget.16642] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 03/06/2017] [Indexed: 12/17/2022] Open
Abstract
A deeper understanding of the complex pathogenesis of multiple myeloma (MM) continues to lead to novel therapeutic approaches. Prior studies suggest that 3-phosphoinositide-dependent kinase 1 (PDK1) is expressed and active, acting as a crucial regulator of molecules that are essential for myelomagenesis. In the present study, we show that GSK2334470 (GSK-470), a novel and highly specific inhibitor of PDK1, induces potent cytotoxicity in MM cell lines including Dexamethasone-resistant cell line, but not in human normal cells. Insulin-like growth factor-1 could not rescue GSK-470-induced cell death. Moreover, GSK-470 down-modulates phosphor-PDK1, thereby inhibiting downstream phosphor-AKT at Thr308 and mTOR complex 1 (mTORC1) activity. However, GSK-470 could not affect mTORC2 activity and phosphor-AKT at Ser473. RPMI 8226 and OPM-2 cells with low expression of PTEN show relative resistant to GSK-470. Knockout of PTEN by shRNA resulted in a partial reversion of GSK-470-mediated growth inhibition, whereas overexpression of PTEN enhanced myeloma cell sensitivity to GSK-470, suggesting that the sensitivity to GSK-470 is correlated with PTEN expression statue in MM cells. Combining PP242, a dual mTORC1/C2 inhibitor, with GSK-470, had greater antimyeloma activity than either one alone in vitro and in MM xenograft model established in immunodeficient mice. In particular, this combination was able to result in a complete inhibition of mTORC1/C2 and full activity of AKT. Together, these findings raise the possibility that combining PDK1 antagonist GSK-470 with mTORC1/C2 inhibitors may represent a novel strategy against MM including drug-resistant myeloma, regardless of PTEN expression status.
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Affiliation(s)
- Chunmei Yang
- Institute of Hematology, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, P.R. China
| | - Xianbo Huang
- Institute of Hematology, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, P.R. China
| | - Hui Liu
- Institute of Hematology, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, P.R. China
| | - Feng Xiao
- Institute of Hematology, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, P.R. China
| | - Jueying Wei
- Institute of Hematology, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, P.R. China
| | - Liangshun You
- Institute of Hematology, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, P.R. China
| | - Wenbin Qian
- Institute of Hematology, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, P.R. China
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20
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Wong CW, Or PMY, Wang Y, Li L, Li J, Yan M, Cao Y, Luk HM, Tong TMF, Leslie NR, Lo IFM, Choy KW, Chan AML. Identification of a PTEN mutation with reduced protein stability, phosphatase activity, and nuclear localization in Hong Kong patients with autistic features, neurodevelopmental delays, and macrocephaly. Autism Res 2018; 11:1098-1109. [PMID: 29608813 PMCID: PMC6220804 DOI: 10.1002/aur.1950] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 01/28/2018] [Accepted: 03/09/2018] [Indexed: 01/04/2023]
Abstract
PTEN is a tumor suppressor gene inactivated in over 30% of human cancers. It encodes a lipid phosphatase that serves as a gatekeeper of the phosphoinositide 3-kinase signaling pathway. Germline mutation frequently occurs in this gene in patients diagnosed with PTEN Hamartoma Tumor Syndrome (PHTS). PHTS individuals are characterized by macrocephaly, benign growth of multiple tissues and increased tumor risk. In addition, autistic phenotypes are found in 10-20% of individuals carrying the germline PTEN mutation with macrocephaly. In this report, 13 suspected PHTS patients were screened for mutation in the PTEN gene. A missense variant (c. 302T > C) substituting the isoleucine at codon 101 to a threonine, a single nucleotide insertion (c. 327-328insC) causing a frame shift mutation and termination at codon 109, and a nonsense variant (c. 1003C > T) truncated the protein at codon 335 were identified. The I101T mutation significantly reduced PTEN protein expression levels by 2.5- to 4.0-fold. Mechanistically, I101T reduced the protein half-life of PTEN possibly due to enhanced polyubiquitination at Lysine 13. However, the I101T mutant retained almost 30% of the lipid phosphatase activity of the wild-type protein. Finally, the I101T mutant has reduced phosphorylation at a PTEN auto-dephosphorylation site at Threonine 366 and a lowered ratio of nuclear to cytosolic protein level. These partial losses of multiple PTEN biochemical functions may contribute to the tissue overgrowth and autistic features of this PHTS patient. Autism Res 2018, 11: 1098-1109. © 2018 The Authors Autism Research published by International Society for Autism Research and Wiley Periodicals, Inc. LAY SUMMARY: The genetics of autism spectrum disorders is highly complex with individual risk influenced by both genetic and environmental factors. Mutation in the human PTEN gene confers a high risk of developing autistic behavior. This report revealed that PTEN mutations occurred in 23% of a selected group of Hong Kong patients harboring autistic features with gross overgrowth symptoms. Detailed characterization of a PTEN mutation revealed reduced protein stability as one of the underlying mechanisms responsible for reduced PTEN activity.
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Affiliation(s)
- Chi Wai Wong
- School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Penelope Mei Yu Or
- School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Yubing Wang
- School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Lisha Li
- School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Jing Li
- School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Mingfei Yan
- School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Ye Cao
- Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Ho Ming Luk
- Clinical Genetic Service, Department of Health, Cheung Sha Wan Jockey Club Clinic, Hong Kong, SAR, China
| | - Tony Ming For Tong
- Clinical Genetic Service, Department of Health, Cheung Sha Wan Jockey Club Clinic, Hong Kong, SAR, China
| | - Nick R Leslie
- Institute of Biological Chemistry, Biophysics and Bio-engineering, Heriot Watt University, Edinburgh, Scotland, UK
| | - Ivan Fai-Man Lo
- Clinical Genetic Service, Department of Health, Cheung Sha Wan Jockey Club Clinic, Hong Kong, SAR, China
| | - Kwong Wai Choy
- Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, SAR, China.,The Chinese University of Hong Kong-Baylor College of Medicine Joint Centre For Medical Genetics, Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Andrew Man Lok Chan
- School of Biomedical Sciences, Lo Kwee-Seong Integrated Biomedical Sciences Building, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Brain and Mind Institute, The Chinese University of Hong Kong, Hong Kong, SAR, China
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21
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Abstract
The cellular hypoxic response contributes to cell transformation and tumor progression. Hypoxia-inducible factor 1 (HIF-1) is a key transcription factor that mediates transcription of genes whose products are essential for cellular adaptation to hypoxia. The activity of HIF-1 is largely regulated by the abundance of its alpha subunit (HIF-1α), which is primarily regulated by an oxygen-dependent and ubiquitin/proteasome-mediated degradation process. The HIF-1α protein level is also regulated by protein kinases through phosphorylation. Polo-like kinase 3 (Plk3) is a serine/threonine protein kinase with a tumor suppressive function. Plk3 phosphorylates and destabilizes HIF-1α. Plk3 also phosphorylates and stabilizes PTEN, a known regulator of HIF-1α stability via the PI3K pathway. Our latest study showed that the Plk3 protein is suppressed by hypoxia or nickel treatment via the ubiquitin/proteasome system. We discovered that Seven in Absentia Homologue 2 (SIAH2) is the E3 ubiquitin ligase of Plk3 and that Plk3 in turn destabilizes SIAH2. Given the role of SIAH2 in promoting stability of HIF-1α, our work reveals a novel mutual regulatory mechanism between Plk3 and SIAH2, which may function to fine-tune the cellular hypoxic response. Here we discuss the role of Plk3 in the hypoxic response and tumorigenesis in light of these latest findings.
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Affiliation(s)
- Dazhong Xu
- a Department of Pathology , New York Medical College School of Medicine , Valhalla , NY , USA
| | - Wei Dai
- b Department of Environmental Medicine , New York University Langone Medical Center , Tuxedo , NY , USA
| | - Cen Li
- a Department of Pathology , New York Medical College School of Medicine , Valhalla , NY , USA
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22
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PTEN, a negative regulator of PI3K/Akt signaling, sustains brain stem cardiovascular regulation during mevinphos intoxication. Neuropharmacology 2017; 123:175-185. [DOI: 10.1016/j.neuropharm.2017.06.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/03/2017] [Accepted: 06/06/2017] [Indexed: 01/06/2023]
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23
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Li C, Park S, Zhang X, Dai W, Xu D. Mutual regulation between Polo-like kinase 3 and SIAH2 E3 ubiquitin ligase defines a regulatory network that fine-tunes the cellular response to hypoxia and nickel. J Biol Chem 2017; 292:11431-11444. [PMID: 28515325 DOI: 10.1074/jbc.m116.767178] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 05/11/2017] [Indexed: 11/06/2022] Open
Abstract
Elevated cellular response to hypoxia, which contributes to cell transformation and tumor progression, is a prominent feature of malignant cells in solid tumors. Polo-like kinase 3 (Plk3) is a serine/threonine protein kinase known to inhibit the cellular response to hypoxia and tumorigenesis. Nickel compounds are well-established human carcinogens that induce tumorigenesis partly through their hypoxia-mimicking effects. Despite previous research efforts, the role of Plk3 in the hypoxic response induced by hypoxia or nickel is not completely understood. Here, we show that NiCl2 (Ni(II)) or hypoxia reduces the protein level and shortens the half-life of cytoplasmic Plk3 in a ubiquitin-proteasome-dependent manner. We identify SIAH2, a RING finger E3 ubiquitin ligase associated with the cellular hypoxic response, to be the ubiquitin E3 ligase that mediates the degradation of Plk3. We show that SIAH2 binds to Plk3 and mediates its ubiquitination primarily through its polo-box domain. We report that USP28, a deubiquitinase known to be inhibitable by Ni(II) or hypoxia, may also contribute to the suppression of the Plk3 protein by Ni(II). We also show that Plk3 in turn suppresses the SIAH2 protein level in a kinase activity-dependent manner. Our study revealed an interesting mutual regulation between Plk3 and SIAH2 and uncovered a regulatory network that functions to fine-tune the cellular hypoxic response. We propose that suppression of Plk3 expression contributes to carcinogenesis and tumor progression induced by nickel compounds.
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Affiliation(s)
- Cen Li
- From the Department of Pathology, School of Medicine, New York Medical College, Valhalla, New York 10595 and
| | - Soyoung Park
- From the Department of Pathology, School of Medicine, New York Medical College, Valhalla, New York 10595 and
| | - Xiaowen Zhang
- From the Department of Pathology, School of Medicine, New York Medical College, Valhalla, New York 10595 and
| | - Wei Dai
- the Department of Environmental Medicine, New York University School of Medicine, Tuxedo, New York 10987
| | - Dazhong Xu
- From the Department of Pathology, School of Medicine, New York Medical College, Valhalla, New York 10595 and
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Ruzzene M, Bertacchini J, Toker A, Marmiroli S. Cross-talk between the CK2 and AKT signaling pathways in cancer. Adv Biol Regul 2017; 64:1-8. [PMID: 28373060 DOI: 10.1016/j.jbior.2017.03.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 03/13/2017] [Indexed: 01/13/2023]
Abstract
CK2 and AKT display a high degree of cross-regulation of their respective functions, both directly, through physical interaction and phosphorylation, and indirectly, through an intense cross-talk of key downstream effectors, ultimately leading to sustained AKT activation. Being CK2 and AKT attractive targets for therapeutic intervention, here we would like to emphasize how AKT and CK2 might influence cell fate through their complex isoform-specific and contextual-dependent cross-talk, to the extent that such functional interplay should be considered when devising therapies that target one or both these key signaling kinases.
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Affiliation(s)
- Maria Ruzzene
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy.
| | - Jessika Bertacchini
- Cell Signaling Unit, Department of Surgery, Medicine, Dentistry and Morphology, University of Modena and Reggio Emilia, 41124 Modena, Italy
| | - Alex Toker
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Sandra Marmiroli
- Cell Signaling Unit, Department of Surgery, Medicine, Dentistry and Morphology, University of Modena and Reggio Emilia, 41124 Modena, Italy.
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25
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Hernández-Sierra A, Rovira J, Petit A, Moya-Rull D, Mazuecos MA, Sánchez-Fructuoso AI, Errasti P, Idoate MÁ, Cruzado JM, Vidal A, Diekmann F, Oppenheimer F, Campistol JM, Revuelta I. Role of HHV-8 and mTOR pathway in post-transplant Kaposi sarcoma staging. Transpl Int 2016; 29:1008-16. [DOI: 10.1111/tri.12800] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 02/09/2016] [Accepted: 05/18/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Astrid Hernández-Sierra
- Department of Nephrology and Renal Transplantation; Hospital Clínic de Barcelona; Barcelona Spain
- Laboratori Experimental de Nefrologia i Trasplantament (LENIT); Fundació Clínic - IDIBAPS; Barcelona Spain
| | - Jordi Rovira
- Laboratori Experimental de Nefrologia i Trasplantament (LENIT); Fundació Clínic - IDIBAPS; Barcelona Spain
| | - Anna Petit
- Department of Pathology; Hospital Clínic de Barcelona; Barcelona Spain
| | - Daniel Moya-Rull
- Laboratori Experimental de Nefrologia i Trasplantament (LENIT); Fundació Clínic - IDIBAPS; Barcelona Spain
| | | | | | - Pedro Errasti
- Department of Nephrology; Clínica Universitaria de Navarra; Pamplona Spain
| | | | | | - August Vidal
- Department of Pathology; Hospital Universitari de Bellvitge; Barcelona Spain
| | - Fritz Diekmann
- Department of Nephrology and Renal Transplantation; Hospital Clínic de Barcelona; Barcelona Spain
- Laboratori Experimental de Nefrologia i Trasplantament (LENIT); Fundació Clínic - IDIBAPS; Barcelona Spain
| | - Federico Oppenheimer
- Department of Nephrology and Renal Transplantation; Hospital Clínic de Barcelona; Barcelona Spain
- Laboratori Experimental de Nefrologia i Trasplantament (LENIT); Fundació Clínic - IDIBAPS; Barcelona Spain
| | - Josep M. Campistol
- Department of Nephrology and Renal Transplantation; Hospital Clínic de Barcelona; Barcelona Spain
- Laboratori Experimental de Nefrologia i Trasplantament (LENIT); Fundació Clínic - IDIBAPS; Barcelona Spain
| | - Ignacio Revuelta
- Department of Nephrology and Renal Transplantation; Hospital Clínic de Barcelona; Barcelona Spain
- Laboratori Experimental de Nefrologia i Trasplantament (LENIT); Fundació Clínic - IDIBAPS; Barcelona Spain
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26
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Benhamou D, Labi V, Novak R, Dai I, Shafir-Alon S, Weiss A, Gaujoux R, Arnold R, Shen-Orr SS, Rajewsky K, Melamed D. A c-Myc/miR17-92/Pten Axis Controls PI3K-Mediated Positive and Negative Selection in B Cell Development and Reconstitutes CD19 Deficiency. Cell Rep 2016; 16:419-431. [DOI: 10.1016/j.celrep.2016.05.084] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/14/2016] [Accepted: 05/19/2016] [Indexed: 01/13/2023] Open
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27
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Wang L, González S, Dai W, Deng S, Lu L. Effect of Hypoxia-regulated Polo-like Kinase 3 (Plk3) on Human Limbal Stem Cell Differentiation. J Biol Chem 2016; 291:16519-29. [PMID: 27281822 DOI: 10.1074/jbc.m116.725747] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Indexed: 11/06/2022] Open
Abstract
Hypoxic conditions in the cornea affect epithelial function by activating Polo-like kinase 3 (Plk3) signaling and the c-Jun·AP-1 transcription complex, resulting in apoptosis of corneal epithelial cells. Hypoxic stress in the culture conditions also regulates limbal stem cell growth and fate. In this study, we demonstrate that there is a differential response of Plk3 in hypoxic stress-induced primary human limbal stem (HLS) and corneal epithelial (HCE) cells, resulting in different pathways of cell fate. We found that hypoxic stress induced HLS cell differentiation by down-regulating Plk3 activity at the transcription level, which was opposite to the effect of hypoxic stress on Plk3 activation to elicit HCE cell apoptosis, detected by DNA fragmentation and TUNEL assays. Hypoxic stress-induced increases in c-Jun phosphorylation/activation were not observed in HLS cells because Plk3 expression and activity were suppressed in hypoxia-induced HLS cells. Instead, hypoxic stress-induced HLS cell differentiation was monitored by cell cycle analysis and measured by the decrease and increase in p63 and keratin 12 expression, respectively. Hypoxic stress-induced Plk3 signaling to regulate c-Jun activity, resulting in limbal stem cell differentiation and center epithelial apoptosis, was also found in the corneas of wild-type and Plk3(-/-)-deficient mice. Our results, for the first time, reveal the differential effects of hypoxic stress on Plk3 activity in HLS and HCE cells. Instead of apoptosis, hypoxic stress suppresses Plk3 activity to protect limbal stem cells from death and to allow the process of HLS cell differentiation.
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Affiliation(s)
- Ling Wang
- From the Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Torrance, California 90502
| | - Sheyla González
- the Department of Ophthalmology, Julie Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, California 91020, and
| | - Wei Dai
- the Department of Environmental Medicine, New York University School of Medicine, Tuxedo, New York 10987
| | - Sophie Deng
- the Department of Ophthalmology, Julie Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, California 91020, and
| | - Luo Lu
- From the Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Torrance, California 90502,
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28
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Helmke C, Becker S, Strebhardt K. The role of Plk3 in oncogenesis. Oncogene 2016; 35:135-47. [PMID: 25915845 DOI: 10.1038/onc.2015.105] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 02/02/2015] [Accepted: 02/02/2015] [Indexed: 01/08/2023]
Abstract
The polo-like kinases (Plks) encompass a family of five serine/threonine protein kinases that play essential roles in many cellular processes involved in the control of the cell cycle, including entry into mitosis, DNA replication and the response to different types of stress. Plk1, which has been validated as a cancer target, came into the focus of many pharmaceutical companies for the development of small-molecule inhibitors as anticancer agents. Recently, FDA (Food and Drug Administration) has granted a breakthrough therapy designation to the Plk inhibitor BI 6727 (volasertib), which provided a survival benefit for patients suffering from acute myeloid leukemia. However, the various ATP-competitive inhibitors of Plk1 that are currently in clinical development also inhibit the activities of Plk2 and Plk3, which are considered as tumor suppressors. Plk3 contributes to the control and progression of the cell cycle while acting as a mediator of apoptosis and various types of cellular stress. The aberrant expression of Plk3 was found in different types of tumors. Recent progress has improved our understanding of Plk3 in regulating stress signaling and tumorigenesis. When using ATP-competitive Plk1 inhibitors, the biological roles of Plk1-related family members like Plk3 in cancer cells need to be considered carefully to improve treatment strategies against cancer.
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Affiliation(s)
- C Helmke
- Department of Obstetrics and Gynecology, School of Medicine, J.W. Goethe University, Frankfurt, Germany
| | - S Becker
- Department of Obstetrics and Gynecology, School of Medicine, J.W. Goethe University, Frankfurt, Germany
| | - K Strebhardt
- Department of Obstetrics and Gynecology, School of Medicine, J.W. Goethe University, Frankfurt, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
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29
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K.M. Ip C, 1 Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA;, Yin J, K.S. Ng P, Lin SY, B. Mills G. Genomic-Glycosylation Aberrations in Tumor Initiation, Progression and Management. AIMS MEDICAL SCIENCE 2016. [DOI: 10.3934/medsci.2016.4.386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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30
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ZHENG JUNFANG, DAI YUANPING, YANG ZHIYU, YANG LONGYAN, PENG ZHIQIANG, MENG RAN, XIONG YING, HE JUNQI. Ezrin-radixin-moesin-binding phosphoprotein-50 regulates EGF-induced AKT activation through interaction with EGFR and PTEN. Oncol Rep 2015; 35:530-7. [DOI: 10.3892/or.2015.4375] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/04/2015] [Indexed: 11/06/2022] Open
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31
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Bermúdez Brito M, Goulielmaki E, Papakonstanti EA. Focus on PTEN Regulation. Front Oncol 2015; 5:166. [PMID: 26284192 PMCID: PMC4515857 DOI: 10.3389/fonc.2015.00166] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 07/07/2015] [Indexed: 12/17/2022] Open
Abstract
The role of phosphatase and tensin homolog on chromosome 10 (PTEN) as a tumor suppressor has been for a long time attributed to its lipid phosphatase activity against PI(3,4,5)P3, the phospholipid product of the class I PI3Ks. Besides its traditional role as a lipid phosphatase at the plasma membrane, a wealth of data has shown that PTEN can function independently of its phosphatase activity and that PTEN also exists and plays a role in the nucleus, in cytoplasmic organelles, and extracellularly. Accumulating evidence has shed light on diverse physiological functions of PTEN, which are accompanied by a complex regulation of its expression and activity. PTEN levels and function are regulated transcriptionally, post-transcriptionally, and post-translationally. PTEN is also sensitive to regulation by its interacting proteins and its localization. Herein, we summarize the current knowledge on mechanisms that regulate the expression and enzymatic activity of PTEN and its role in human diseases.
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Affiliation(s)
- Miriam Bermúdez Brito
- Department of Biochemistry, School of Medicine, University of Crete , Heraklion , Greece
| | - Evangelia Goulielmaki
- Department of Biochemistry, School of Medicine, University of Crete , Heraklion , Greece
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32
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Yang H, Fang L, Zhan R, Hegarty JM, Ren J, Hsiai TK, Gleeson JG, Miller YI, Trejo J, Chi NC. Polo-like kinase 2 regulates angiogenic sprouting and blood vessel development. Dev Biol 2015; 404:49-60. [PMID: 26004360 DOI: 10.1016/j.ydbio.2015.05.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 04/11/2015] [Accepted: 05/12/2015] [Indexed: 02/07/2023]
Abstract
Angiogenesis relies on specialized endothelial tip cells to extend toward guidance cues in order to direct growing blood vessels. Although many of the signaling pathways that control this directional endothelial sprouting are well known, the specific cellular mechanisms that mediate this process remain to be fully elucidated. Here, we show that Polo-like kinase 2 (PLK2) regulates Rap1 activity to guide endothelial tip cell lamellipodia formation and subsequent angiogenic sprouting. Using a combination of high-resolution in vivo imaging of zebrafish vascular development and a human umbilical vein endothelial cell (HUVEC) in vitro cell culture system, we observed that loss of PLK2 function resulted in a reduction in endothelial cell sprouting and migration, whereas overexpression of PLK2 promoted angiogenesis. Furthermore, we discovered that PLK2 may control angiogenic sprouting by binding to PDZ-GEF to regulate RAP1 activity during endothelial cell lamellipodia formation and extracellular matrix attachment. Consistent with these findings, constitutively active RAP1 could rescue the endothelial cell sprouting defects observed in zebrafish and HUVEC PLK2 knockdowns. Overall, these findings reveal a conserved PLK2-RAP1 pathway that is crucial to regulate endothelial tip cell behavior in order to ensure proper vascular development and patterning in vertebrates.
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Affiliation(s)
- Hongbo Yang
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0613J, USA
| | - Longhou Fang
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0613J, USA
| | - Rui Zhan
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0613J, USA
| | - Jeffrey M Hegarty
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0613J, USA
| | - Jie Ren
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0613J, USA
| | - Tzung K Hsiai
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA, USA; Department of Bioengineering, School of Engineering & Applied Science, University of California, Los Angeles, CA, USA
| | - Joseph G Gleeson
- Neurogenetics Laboratory, Howard Hughes Medical Institute, Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yury I Miller
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0613J, USA
| | - JoAnn Trejo
- Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Neil C Chi
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0613J, USA; Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
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33
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Fragoso R, Barata JT. Kinases, tails and more: regulation of PTEN function by phosphorylation. Methods 2015; 77-78:75-81. [PMID: 25448482 DOI: 10.1016/j.ymeth.2014.10.015] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 10/10/2014] [Accepted: 10/15/2014] [Indexed: 12/15/2022] Open
Abstract
Phosphorylation regulates the conformation, stability, homo- and heterotypic protein interactions, localization, and activity of the tumor suppressor PTEN. From a simple picture, at the beginning of this millennium, recognizing that CK2 phosphorylated PTEN at the C-terminus and thereby impacted on PTEN stability and activity, research has led to a significantly more complex scenario today, where for instance GSK3, Plk3, ATM, ROCK or Src-family kinases are also gaining the spotlight in this evolving play. Here, we review the current knowledge on the kinases that phosphorylate PTEN, and on the impact that specific phosphorylation events have on PTEN function.
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Affiliation(s)
- Rita Fragoso
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisboa, Portugal
| | - João T Barata
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisboa, Portugal.
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34
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Quantitative and dynamic analysis of PTEN phosphorylation by NMR. Methods 2015; 77-78:82-91. [DOI: 10.1016/j.ymeth.2014.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 09/29/2014] [Accepted: 10/07/2014] [Indexed: 12/15/2022] Open
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35
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Olaisen C, Müller R, Nedal A, Otterlei M. PCNA-interacting peptides reduce Akt phosphorylation and TLR-mediated cytokine secretion suggesting a role of PCNA in cellular signaling. Cell Signal 2015; 27:1478-87. [PMID: 25797046 DOI: 10.1016/j.cellsig.2015.03.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 03/12/2015] [Indexed: 01/14/2023]
Abstract
Proliferating cell nuclear antigen (PCNA), commonly known as a nuclear protein essential for regulation of DNA replication, DNA repair, and epigenetics, has recently been associated with multiple cytosolic functions. Many proteins containing one of the two known PCNA-interacting motifs, the AlkB homologue 2 PCNA interacting motif (APIM) and the PCNA-interacting peptide (PIP)-box, are considered to be mainly cytosolic. APIM is found in more than 20 kinases and/or associated proteins including several direct or indirect members of the mitogen-activated protein kinase (MAPK) and PI3K/Akt pathways. Mass spectrometry analysis of PCNA-pull downs verified that many cytosolic proteins involved in the MAPK and PI3K/Akt pathways are in complex with PCNA. Furthermore, treatment of cells with a PCNA-interacting APIM-containing peptide (APIM-peptide) reduced Akt phosphorylation in human peripheral blood monocytes and a human keratinocyte cell line (HaCaT). Additionally, the APIM-peptide strongly reduced the cytokine secretion from monocytes stimulated with toll like receptor (TLR) ligands and potentiated the effects of MAPK and PI3K/Akt inhibitors. Interestingly, the protein level of the APIM-containing PKR/RIG-1 activator protein (PACT) was initially strongly reduced in HaCaT cells stimulated with APIM-peptide in combination with the TLR ligand polyinosinic-polycytidylic acid (polyIC). Our results suggest that PCNA has a platform role in cytosol affecting cellular signaling.
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Affiliation(s)
- Camilla Olaisen
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway
| | - Rebekka Müller
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway
| | - Aina Nedal
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway
| | - Marit Otterlei
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway.
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Uversky VN, Davé V, Iakoucheva LM, Malaney P, Metallo SJ, Pathak RR, Joerger AC. Pathological unfoldomics of uncontrolled chaos: intrinsically disordered proteins and human diseases. Chem Rev 2014; 114:6844-79. [PMID: 24830552 PMCID: PMC4100540 DOI: 10.1021/cr400713r] [Citation(s) in RCA: 214] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Vladimir N. Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer’s Research Institute University of South Florida, Tampa, Florida 33612, United States
- Institute for Biological Instrumentation, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 22254, Saudi Arabia
| | - Vrushank Davé
- Department of Pathology and Cell Biology , Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, United States
- Department of Molecular Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, United States
| | - Lilia M. Iakoucheva
- Department of Psychiatry, University of California San Diego, La Jolla, California 92093, United States
| | - Prerna Malaney
- Department of Pathology and Cell Biology , Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, United States
| | - Steven J. Metallo
- Department of Chemistry, Georgetown University, Washington, District of Columbia 20057, United States
| | - Ravi Ramesh Pathak
- Department of Pathology and Cell Biology , Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, United States
| | - Andreas C. Joerger
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom
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Craig SN, Wyatt MD, McInnes C. Current assessment of polo-like kinases as anti-tumor drug targets. Expert Opin Drug Discov 2014; 9:773-89. [PMID: 24819909 DOI: 10.1517/17460441.2014.918100] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
INTRODUCTION Polo-like kinase (PLK)1 is the most studied of the PLK family and is a serine/threonine kinase that plays pivotal roles in many aspects of mitosis and hence its deregulation is prevalent in various malignant tumor types. AREAS COVERED In this review, the authors discuss the relevancy of PLK1 and other PLK members as oncology targets in light of known roles of these kinases and the observed phenotypic consequence of downregulating their activity, depending on how they are targeted. Furthermore, they also discuss the pathways mutated in cancer that have been shown to enhance sensitivity toward PLK1 inhibitors in the context of tumor types that possess these molecular defects. They also summarize preclinical and clinical investigations that have been undertaken for both ATP and non-ATP competitive inhibitors. EXPERT OPINION PLKs 2, 3 and 5 are primarily linked with tumor suppressor functions and as PLK1 is the most validated anticancer drug target, selective inhibitors for its activities are most likely to result in effective therapeutics with reduced side effects. In this regard, the polo box domain can be targeted to generate selective inhibitors of PLK1 while preventing inhibition of kinases outside of this family. Recent studies confirming the synthetic lethality of other molecular defects with PLK1 can be exploited to obtain tumor selective apoptosis in p53, KRAS and PTEN mutant cancers.
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Affiliation(s)
- Sandra N Craig
- University of South Carolina, South Carolina College of Pharmacy, Drug Discovery and Biomedical Sciences , Columbia, SC, 29208 , USA +1 803 576 5684 ;
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38
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Choi BH, Pagano M, Dai W. Plk1 protein phosphorylates phosphatase and tensin homolog (PTEN) and regulates its mitotic activity during the cell cycle. J Biol Chem 2014; 289:14066-74. [PMID: 24706748 PMCID: PMC4022876 DOI: 10.1074/jbc.m114.558155] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 03/30/2014] [Indexed: 01/21/2023] Open
Abstract
PTEN is a well known tumor suppressor through the negative regulation of the PI3K signaling pathway. Here we report that PTEN plays an important role in regulating mitotic timing, which is associated with increased PTEN phosphorylation in the C-terminal tail and its localization to chromatin. Pulldown analysis revealed that Plk1 physically interacted with PTEN. Biochemical studies showed that Plk1 phosphorylates PTEN in vitro in a concentration-dependent manner and that the phosphorylation was inhibited by Bi2635, a Plk1-specific inhibitor. Deletional and mutational analyses identified that Plk1 phosphorylated Ser-380, Thr-382, and Thr-383, but not Ser-385, a cluster of residues known to affect the PTEN stability. Interestingly, a combination of molecular and genetic analyses revealed that only Ser-380 was significantly phosphorylated in vivo and that Plk1 regulated the phosphorylation, which was associated with the accumulation of PTEN on chromatin. Moreover, expression of phospho-deficient mutant, but not wild-type PTEN, caused enhanced mitotic exit. Taken together, our studies identify Plk1 as an important regulator of PTEN during the cell cycle.
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Affiliation(s)
- Byeong Hyeok Choi
- From the Departments of Environmental Medicine, Biochemistry, and Molecular Pharmacology, New York University School of Medicine, Tuxedo, New York 10987
| | - Michele Pagano
- the Department of Pathology, New York University Cancer Institute, New York University School of Medicine, New York, New York 10016, and the Howard Hughes Medical Institute, New York University School of Medicine, New York, New York 10016
| | - Wei Dai
- From the Departments of Environmental Medicine, Biochemistry, and Molecular Pharmacology, New York University School of Medicine, Tuxedo, New York 10987,
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Choi BH, Pagano M, Huang C, Dai W. Cdh1, a substrate-recruiting component of anaphase-promoting complex/cyclosome (APC/C) ubiquitin E3 ligase, specifically interacts with phosphatase and tensin homolog (PTEN) and promotes its removal from chromatin. J Biol Chem 2014; 289:17951-9. [PMID: 24811168 DOI: 10.1074/jbc.m114.559005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A pool of PTEN localizes to the nucleus. However, the exact mechanism by which nuclear PTEN is regulated remains unclear. We have recently reported that Plk1 specifically phosphorylates PTEN on Ser-380 during mitosis. Here we report that PTEN also localized to chromatin and that chromatin PTEN was removed by a proteasome-dependent process during mitotic exit. Pulldown analysis revealed that Cdh1, but not Cdc20, was significantly associated with PTEN. Cdh1 interacted with PTEN via two separate domains, and their interaction was enhanced by MG132, a proteasome inhibitor. Cdh1 negatively controlled the stability of chromatin PTEN by polyubiquitination. Phosphorylation of PTEN on Ser-380 impaired its interaction with Cdh1, thus positively regulating PTEN stability on chromatin. Significantly, the PTEN interaction with Cdh1 was phosphatase-independent, and Cdh1 knockdown via RNAi led to significant accumulation of chromatin PTEN, delaying mitotic exit. Combined, our studies identify Cdh1 as an important regulator of nuclear/chromatin PTEN during mitosis.
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Affiliation(s)
- Byeong Hyeok Choi
- From the Departments of Environmental Medicine, Biochemistry, and Molecular Pharmacology, New York University School of Medicine, Tuxedo, New York 10987
| | - Michele Pagano
- the Department of Pathology, New York University Cancer Institute, New York University School of Medicine, New York, New York 10016, and the Howard Hughes Medical Institute, New York University School of Medicine, New York, New York 10016
| | - Chaunshu Huang
- From the Departments of Environmental Medicine, Biochemistry, and Molecular Pharmacology, New York University School of Medicine, Tuxedo, New York 10987
| | - Wei Dai
- From the Departments of Environmental Medicine, Biochemistry, and Molecular Pharmacology, New York University School of Medicine, Tuxedo, New York 10987,
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Choi BH, Chen Y, Dai W. Chromatin PTEN is involved in DNA damage response partly through regulating Rad52 sumoylation. Cell Cycle 2013; 12:3442-7. [PMID: 24047694 DOI: 10.4161/cc.26465] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
A pool of PTEN localizes to the nucleus. However, the exact mechanism of action of nuclear PTEN remains poorly understood. We have investigated PTEN's role during DNA damage response. Here we report that PTEN undergoes chromatin translocation after DNA damage, and that its translocation is closely associated with its phosphorylation on S366/T370 but not on S380. Deletional analysis reveals that the C2 domain of PTEN is responsible for its nuclear translocation after exposure to genotoxin. Both casein kinase 2 and GSK3β are involved in the phosphorylation of the S366/T370 epitope, as well as PTEN's association with chromatin after DNA damage. Significantly, PTEN specifically interacts with Rad52 and colocalizes with Rad52, as well as γH2AX, after genotoxic stress. Moreover, PTEN is involved in regulating Rad52 sumoylation. Combined, our studies strongly suggest that nuclear/chromatin PTEN mediates DNA damage repair through interacting with and modulating the activity of Rad52.
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Affiliation(s)
- Byeong Hyeok Choi
- Departments of Environmental Medicine, Biochemistry, and Molecular Pharmacology; New York University School of Medicine; Tuxedo, NY USA
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41
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Cayado-Gutiérrez N, Moncalero VL, Rosales EM, Berón W, Salvatierra EE, Alvarez-Olmedo D, Radrizzani M, Ciocca DR. Downregulation of Hsp27 (HSPB1) in MCF-7 human breast cancer cells induces upregulation of PTEN. Cell Stress Chaperones 2013; 18:243-9. [PMID: 22907762 PMCID: PMC3581620 DOI: 10.1007/s12192-012-0367-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 08/03/2012] [Accepted: 08/06/2012] [Indexed: 12/14/2022] Open
Abstract
Hsp27 (HSPB1) is usually overexpressed in breast cancers affecting the disease outcome and the sensitivity of tumors to chemotherapy and radiotherapy. Hsp27 interacts with other proteins such as β-catenin, histone deacetylase HDAC6, transcription factor STAT2 and procaspase-3. Phosphatase and tensin homologue (PTEN) is a tumor suppressor gene that is deleted in many human tumors. The PI3K/Akt signaling pathway is negatively regulated by PTEN. Hsp27 is described as a key component of the Akt signaling cascade: Akt, BAD, Forkhead transcription factors, Hsp27, mitogen-activated protein kinase kinase-3 and -6. Here, we have examined whether the downregulation of Hsp27 by siHsp27 affects the PTEN levels in the MCF-7 human breast cancer cell line. PTEN was detected with two different antibodies using western blots and immunocytochemistry. p-Akt was also evaluated by western blot. In addition, Hsp27 and PTEN were immunoprecipitated to know whether these proteins interact. Intracellular colocalization studies were carried out by confocal microscopy. A significant reduction in the Hsp27 levels was noted in the siHsp27 transfected cells. These Hsp27 downregulated cells showed a significant increased expression of PTEN. The MW 76 and 55 kDa PTEN forms were upregulated as revealed by two different antibodies. The phosphatase activity of PTEN seems to be active because p-Akt levels were reduced. Hsp27 immunoprecipitation was bringing PTEN and vice versa, these two proteins seem to interact at cytoplasmic level by FRET. Downregulation of Hsp27 stabilized PTEN protein levels. Chaperone-assisted E3 ligase C terminus of Hsc70-interacting protein (CHIP) levels were not significantly influenced by Hsp27 downregulation. In conclusion, we report a novel function of Hsp27 modulating the PTEN levels in human breast cancer cells suggesting an interaction between these two molecules.
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Affiliation(s)
- Niubys Cayado-Gutiérrez
- />Laboratory of Oncology, IMBECU, CCT-CONICET, National Research Council, C.C. 855, Mendoza, Argentina
| | - Vera L. Moncalero
- />Laboratorio de Neuro y Citogenética Molecular, Centro de Estudios de Salud y Medio Ambiente, UN de San Martín, CONICET, Buenos Aires, Argentina
| | - Eliana M. Rosales
- />Instituto de Histología y Embriología, Facultad de Ciencias Médicas, UNCuyo, CONICET, Mendoza, Argentina
| | - Walter Berón
- />Instituto de Histología y Embriología, Facultad de Ciencias Médicas, UNCuyo, CONICET, Mendoza, Argentina
| | - Edgardo E. Salvatierra
- />Molecular and Cellular Therapy Laboratory, Instituto F. Leloir-IBBA-CONICET, Buenos Aires, Argentina
| | - Daiana Alvarez-Olmedo
- />Laboratory of Oncology, IMBECU, CCT-CONICET, National Research Council, C.C. 855, Mendoza, Argentina
| | - Martín Radrizzani
- />Laboratorio de Neuro y Citogenética Molecular, Centro de Estudios de Salud y Medio Ambiente, UN de San Martín, CONICET, Buenos Aires, Argentina
| | - Daniel R. Ciocca
- />Laboratory of Oncology, IMBECU, CCT-CONICET, National Research Council, C.C. 855, Mendoza, Argentina
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Cordier F, Chaffotte A, Terrien E, Préhaud C, Theillet FX, Delepierre M, Lafon M, Buc H, Wolff N. Ordered Phosphorylation Events in Two Independent Cascades of the PTEN C-tail Revealed by NMR. J Am Chem Soc 2012; 134:20533-43. [DOI: 10.1021/ja310214g] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
| | | | - Elouan Terrien
- CNRS, UMR3528, F-75015 Paris, France
- Cellule Pasteur UPMC, University of Pierre and Marie Curie, rue du Dr Roux,
75015 Paris, France
| | | | | | | | | | - Henri Buc
- Institut Pasteur,
F-75015 Paris, France
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McInnes C, Estes K, Baxter M, Yang Z, Farag DB, Johnston P, Lazo JS, Wang J, Wyatt MD. Targeting subcellular localization through the polo-box domain: non-ATP competitive inhibitors recapitulate a PLK1 phenotype. Mol Cancer Ther 2012; 11:1683-92. [PMID: 22848093 PMCID: PMC3711794 DOI: 10.1158/1535-7163.mct-12-0006-t] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The polo-box domain (PBD) has critical roles in the mitotic functions of polo-like kinase 1 (PLK1). The replacement with partial ligand alternative through computational enrichment (REPLACE) strategy to develop inhibitors of protein-protein interactions has identified alternatives for the N-terminal tripeptide of a Cdc25C substrate. In addition, a peptide structure-activity relationship described key determinants and novel information useful for drug design. Fragment-ligated inhibitory peptides (FLIP) were generated with comparable affinity to peptide PBD inhibitors and possessed antiproliferative phenotypes in cells consistent with the observed decrease in PLK1 centrosomal localization. These FLIPs showed evidence of enhanced PLK1 inhibition in cells relative to peptides and induced monopolar and multipolar spindles, which stands in contrast to previously reported small-molecule PBD inhibitors that display phenotypes only partially representative of PLK1 knockdown. Progress obtained applying REPLACE validates this approach for identifying fragment alternatives for determinants of the Cdc25C-binding motif and extends its applicability of the strategy for discovering protein-protein interaction inhibitors. In addition, the described PBD inhibitors retain high specificity for PLK1 over PLK3 and therefore show promise as isotype selective, non-ATP competitive kinase inhibitors that provide new impetus for the development of PLK1-selective antitumor therapeutics.
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Affiliation(s)
- Campbell McInnes
- Pharmaceutical and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA.
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44
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Edimo WE, Janssens V, Waelkens E, Erneux C. Reversible Ser/Thr SHIP phosphorylation: a new paradigm in phosphoinositide signalling?: Targeting of SHIP1/2 phosphatases may be controlled by phosphorylation on Ser and Thr residues. Bioessays 2012; 34:634-42. [PMID: 22641604 DOI: 10.1002/bies.201100195] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Phosphoinositide (PI) phosphatases such as the SH2 domain-containing inositol 5-phosphatases 1/2 (SHIP1 and 2) are important signalling enzymes in human physiopathology. SHIP1/2 interact with a large number of immune and growth factor receptors. Tyrosine phosphorylation of SHIP1/2 has been considered to be the determining regulatory modification. However, here we present a hypothesis, based on recent key publications, highlighting the determining role of Ser/Thr phosphorylation in regulating several key properties of SHIP1/2. Since a subunit of the Ser/Thr phosphatase PP2A has been shown to interact with SHIP2, a putative mechanism for reversing SHIP2 Ser/Thr phosphorylation can be anticipated. PI phosphatases are potential target molecules in human diseases, particularly, but not exclusively, in cancer and diabetes. Therefore, this novel regulatory mechanism deserves further attention in the hunt for discovering novel or complementary therapeutic strategies. This mechanism may be more broadly involved in regulating PI signalling in the case of synaptojanin1 or the phosphatase, tensin homolog, deleted on chromosome TEN.
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Affiliation(s)
- William's Elong Edimo
- Institut de Recherche Interdisciplinaire (IRIBHM), Université Libre de Bruxelles, Campus Erasme, Brussels, Belgium
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45
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Zhang P, Chen JH, Guo XL. New insights into PTEN regulation mechanisms and its potential function in targeted therapies. Biomed Pharmacother 2012; 66:485-90. [PMID: 22902055 DOI: 10.1016/j.biopha.2012.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 04/15/2012] [Indexed: 12/12/2022] Open
Abstract
Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a tumor suppressor gene of phosphatased activity. Its low or lacking expression closely relates with tumor progress and poor prognosis. The regulation and function ascribed to PTEN have become more diverse since its discovery as a putative phosphatase mutated in many human tumors. PTEN function is positively and negatively regulated at the transcriptional level, as well as post-translationally by phosphorylation, oxidation and acetylation. Deregulation of PTEN is implicated in other human diseases in addition to cancers, including diabetes and obesity, modulation of PTEN level has widespread therapeutic applications to those tumorigenesis and non-tumor diseases. This review will summarize the new points on the regulation of PTEN and briefly discuss the potential therapeutic role of PTEN in some diseases.
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Affiliation(s)
- Peng Zhang
- Department of Pharmacology, School of Pharmaceutical Sciences, Shandong University, Jinan, PR China
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46
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Xu D, Wang Q, Jiang Y, Zhang Y, Vega-Saenzdemiera E, Osman I, Dai W. Roles of Polo-like kinase 3 in suppressing tumor angiogenesis. Exp Hematol Oncol 2012; 1:5. [PMID: 23210979 PMCID: PMC3506990 DOI: 10.1186/2162-3619-1-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 04/18/2012] [Indexed: 02/08/2023] Open
Abstract
Angiogenesis is essential for promoting growth and metastasis of solid tumors by ensuring blood supply to the tumor mass. Targeting angiogenesis is therefore an attractive approach to therapeutic intervention of cancer. Tumor angiogenesis is a process that is controlled by a complex network of molecular components including sensors, signaling transducers, and effectors, leading to cellular responses under hypoxic conditions. Positioned at the center of this network are the hypoxia-inducible factors (HIFs). HIF-1 is a major transcription factor that consists of two subunits, HIF-1α and HIF-1β. It mediates transcription of a spectrum of gene targets whose products are essential for mounting hypoxic responses. HIF-1α protein level is very low in the normoxic condition but is rapidly elevated under hypoxia. This dramatic change in the cellular HIF-1α level is primarily regulated through the proteosome-mediated degradation process. In the past few years, scientific progress has clearly demonstrated that HIF-1α phosphorylation is mediated by several families of protein kinases including GSK3β and ERKs both of which play crucial roles in the regulation of HIF-1α stability. Recent research progress has identified that Polo-like kinase 3 (Plk3) phosphorylates HIF-1α at two previously unidentified serine residues and that the Plk3-mediated phosphorylation of these residues results in destabilization of HIF-1α. Plk3 has also recently been found to phosphorylate and stabilize PTEN phosphatase, a known regulator of HIF-1α and tumor angiogenesis. Given the success of targeting protein kinases and tumor angiogenesis in anti-cancer therapies, Plk3 could be a potential molecular target for the development of novel and effective therapeutic agents for cancer treatment.
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Affiliation(s)
- Dazhong Xu
- Department of Environmental Medicine, New York University Langone Medical Center, 57 Old Forge Road, Tuxedo, NY 10987, USA.
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Song MS, Salmena L, Pandolfi PP. The functions and regulation of the PTEN tumour suppressor. Nat Rev Mol Cell Biol 2012; 13:283-96. [PMID: 22473468 DOI: 10.1038/nrm3330] [Citation(s) in RCA: 1508] [Impact Index Per Article: 116.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The importance of the physiological function of phosphatase and tensin homologue (PTEN) is illustrated by its frequent disruption in cancer. By suppressing the phosphoinositide 3-kinase (PI3K)-AKT-mammalian target of rapamycin (mTOR) pathway through its lipid phosphatase activity, PTEN governs a plethora of cellular processes including survival, proliferation, energy metabolism and cellular architecture. Consequently, mechanisms regulating PTEN expression and function, including transcriptional regulation, post-transcriptional regulation by non-coding RNAs, post-translational modifications and protein-protein interactions, are all altered in cancer. The repertoire of PTEN functions has recently been expanded to include phosphatase-independent activities and crucial functions within the nucleus. Our increasing knowledge of PTEN and pathologies in which its function is altered will undoubtedly inform the rational design of novel therapies.
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Affiliation(s)
- Min Sup Song
- Cancer Genetics Program, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Harvard Medical School, Boston, Massachuchetts 02215, USA.
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Stelter L, Evans MJ, Jungbluth AA, Zanzonico P, Ritter G, Ku T, Rosenfeld E, Bomalaski JS, Old L, Larson SM. Novel mechanistic insights into arginine deiminase pharmacology suggest 18F-FDG is not suitable to evaluate clinical response in melanoma. J Nucl Med 2012; 53:281-6. [PMID: 22228793 DOI: 10.2967/jnumed.111.092973] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Because of deficiencies in l-arginine biosynthesis, some cancers are susceptible to therapeutic intervention with arginine deiminase (ADI), an enzyme responsible for consuming the dietary supply of l-arginine to deprive the disease of an essential nutrient. ADI is currently being evaluated in several clinical trials, and fully realizing the drug's potential will depend on invoking the appropriate metrics to judge clinical response. Without a clear biologic mandate, PET/CT with (18)F-FDG is currently used to monitor patients treated with ADI. However, it is unclear if it can be expected that (18)F-FDG responses will indicate (or predict) clinical benefit. METHODS (18)F-FDG responses to ADI therapy were studied in preclinical models of melanoma in vitro and in vivo. The molecular mechanism of response to ADI therapy was also studied, with a particular emphasis on biologic pathways known to regulate (18)F-FDG avidity. RESULTS Although proliferation of SK-MEL 28 was potently inhibited by ADI treatment in vitro and in vivo, no clear declines in (18)F-FDG uptake were observed. Further investigation showed that ADI treatment induces the posttranslational degradation of phosphatase and tensin homolog and the activation of the PI3K signaling pathway, an event known to enhance glycolysis and (18)F-FDG avidity. A more thorough mechanistic study showed that ADI triggered a complex mechanism of cell death, involving apoptosis via poly (ADP-ribose) polymerase cleavage-independent of caspase 3. CONCLUSION These findings suggest that some unexpected pharmacologic properties of ADI preclude using (18)F-FDG to evaluate clinical response in melanoma and, more generally, argue for further studies to explore the use of PET tracers that target apoptotic pathway activation or cell death.
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Affiliation(s)
- Lars Stelter
- Nuclear Medicine Service, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
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Paweletz CP, Andersen JN, Pollock R, Nagashima K, Hayashi ML, Yu SU, Guo H, Bobkova EV, Xu Z, Northrup A, Blume-Jensen P, Hendrickson RC, Chi A. Identification of direct target engagement biomarkers for kinase-targeted therapeutics. PLoS One 2011; 6:e26459. [PMID: 22039492 PMCID: PMC3200335 DOI: 10.1371/journal.pone.0026459] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 09/27/2011] [Indexed: 11/18/2022] Open
Abstract
Pharmacodynamic (PD) biomarkers are an increasingly valuable tool for decision-making and prioritization of lead compounds during preclinical and clinical studies as they link drug-target inhibition in cells with biological activity. They are of particular importance for novel, first-in-class mechanisms, where the ability of a targeted therapeutic to impact disease outcome is often unknown. By definition, proximal PD biomarkers aim to measure the interaction of a drug with its biological target. For kinase drug discovery, protein substrate phosphorylation sites represent candidate PD biomarkers. However, substrate phosphorylation is often controlled by input from multiple converging pathways complicating assessment of how potently a small molecule drug hits its target based on substrate phoshorylation measurements alone. Here, we report the use of quantitative, differential mass-spectrometry to identify and monitor novel drug-regulated phosphorylation sites on target kinases. Autophosphorylation sites constitute clinically validated biomarkers for select protein tyrosine kinase inhibitors. The present study extends this principle to phosphorylation sites in serine/threonine kinases looking beyond the T-loop autophosphorylation site. Specifically, for the 3'-phosphoinositide-dependent protein kinase 1 (PDK1), two phospho-residues p-PDK1(Ser410) and p-PDK1(Thr513) are modulated by small-molecule PDK1 inhibitors, and their degree of dephosphorylation correlates with inhibitor potency. We note that classical, ATP-competitive PDK1 inhibitors do not modulate PDK1 T-loop phosphorylation (p-PDK1(Ser241)), highlighting the value of an unbiased approach to identify drug target-regulated phosphorylation sites as these are complementary to pathway PD biomarkers. Finally, we extend our analysis to another protein Ser/Thr kinase, highlighting a broader utility of our approach for identification of kinase drug-target engagement biomarkers.
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Affiliation(s)
| | | | - Roy Pollock
- Merck & Co., Inc., Boston, Massachusetts, United States of America
| | - Kumiko Nagashima
- Merck & Co., Inc., Boston, Massachusetts, United States of America
| | - Mansuo L. Hayashi
- Merck & Co., Inc., Boston, Massachusetts, United States of America
- Merck & Co., Inc., West Point, Pennsylvania, United States of America
| | - Shangshuan U. Yu
- Merck & Co., Inc., Boston, Massachusetts, United States of America
| | - Hongbo Guo
- Merck & Co., Inc., Boston, Massachusetts, United States of America
| | | | - Zangwei Xu
- Merck & Co., Inc., Boston, Massachusetts, United States of America
| | - Alan Northrup
- Merck & Co., Inc., Boston, Massachusetts, United States of America
| | - Peter Blume-Jensen
- Metamark Genetics, Inc, Cambridge, Massachusettes, United States of America
- * E-mail: (PBJ); (AC)
| | | | - An Chi
- Merck & Co., Inc., Boston, Massachusetts, United States of America
- * E-mail: (PBJ); (AC)
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50
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McInnes C, Wyatt MD. PLK1 as an oncology target: current status and future potential. Drug Discov Today 2011; 16:619-25. [PMID: 21601650 DOI: 10.1016/j.drudis.2011.05.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 03/24/2011] [Accepted: 05/06/2011] [Indexed: 10/18/2022]
Abstract
The Polo-like kinases (PLKs) have been investigated as oncology targets for several years; however, only recently have potent inhibitors been described. Here, we report on progress in the clinical validation of the PLKs as antitumor drug targets as well as recent understanding gained regarding their synergistic roles in the context of other molecular defects occurring in tumors. Also relevant to the development of PLK inhibitors as therapeutics are the putative roles of other members of this family as tumor suppressors. The resulting potential drawbacks of non-isoform selective compounds are presented. As an alternative approach to achieving PLK1 specificity, we discuss prospects for developing small molecule inhibitors of the crucial regulatory and subcellular targeting domain containing the Polo-boxes.
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Affiliation(s)
- Campbell McInnes
- Pharmaceutical and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA.
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