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Zorina-Lichtenwalter K, Ase AR, Verma V, Parra AIM, Komarova S, Khadra A, Séguéla P, Diatchenko L. Characterization of Common Genetic Variants in P2RX7 and Their Contribution to Chronic Pain Conditions. THE JOURNAL OF PAIN 2024; 25:545-556. [PMID: 37742908 DOI: 10.1016/j.jpain.2023.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 08/22/2023] [Accepted: 09/19/2023] [Indexed: 09/26/2023]
Abstract
The adenosine triphosphate (ATP)-gated channel P2X7 is encoded by a gene enriched for common nonsynonymous variants. Many of these variants have functional cellular effects, and some have been implicated in chronic pain. In this study, we first systematically characterized all 17 common nonsynonymous variants using whole-cell patch clamp electrophysiology. Then, we analyzed these variants for statistical association with chronic pain phenotypes using both individual P2RX7 variants as predictors and cumulative allele counts of same-direction cellular effect in univariate models. Association and validation analyses were conducted in the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) cohort (N = 3260) and in the Complex Persistent Pain Conditions (CPPC) cohort (N = 900), respectively. Our results showed an association between allele A of rs7958311 and an increased risk of chronic pelvic pain, with convergent evidence for contribution to fibromyalgia and irritable bowel syndrome, confirmed in a meta-analysis. This allelic variant produced a unique cellular phenotype: a gain-of-function in channel opening, and a loss-of-function in pore opening. A computational study using a 12-state Markov model of ATP binding to the P2X7 receptor suggested that this cellular phenotype arises from an increased ATP binding affinity and an increased open channel conductance combined with a loss of sensitization. Cumulative allele count analysis did not provide additional insights. In conclusion, our results go beyond reproducing association for rs7958311 with chronic pain and suggest that its unique combination of gain-of-function in channel and loss-of-function in pore activity may explain why it is likely the only common P2RX7 variant with contribution to chronic pain. PERSPECTIVE: This study characterizes all common P2RX7 variants using cellular assays and statistical association analyses with chronic pain, with Markov state modeling of the most robustly associated variant.
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Affiliation(s)
- Katerina Zorina-Lichtenwalter
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Ariel R Ase
- Department of Neurology & Neurosurgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Montreal Neurological Institute/Hospital, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Vivek Verma
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Arturo I M Parra
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Svetlana Komarova
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Anmar Khadra
- Department of Physiology, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Philippe Séguéla
- Department of Neurology & Neurosurgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Montreal Neurological Institute/Hospital, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Luda Diatchenko
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
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2
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Tewari M, Michalski S, Egan TM. Modulation of Microglial Function by ATP-Gated P2X7 Receptors: Studies in Rat, Mice and Human. Cells 2024; 13:161. [PMID: 38247852 PMCID: PMC10814008 DOI: 10.3390/cells13020161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 01/23/2024] Open
Abstract
P2X receptors are a family of seven ATP-gated ion channels that trigger physiological and pathophysiological responses in a variety of cells. Five of the family members are sensitive to low concentrations of extracellular ATP, while the P2X6 receptor has an unknown affinity. The last subtype, the P2X7 receptor, is unique in requiring millimolar concentrations to fully activate in humans. This low sensitivity imparts the agonist with the ability to act as a damage-associated molecular pattern that triggers the innate immune response in response to the elevated levels of extracellular ATP that accompany inflammation and tissue damage. In this review, we focus on microglia because they are the primary immune cells of the central nervous system, and they activate in response to ATP or its synthetic analog, BzATP. We start by introducing purinergic receptors and then briefly consider the roles that microglia play in neurodevelopment and disease by referencing both original works and relevant reviews. Next, we move to the role of extracellular ATP and P2X receptors in initiating and/or modulating innate immunity in the central nervous system. While most of the data that we review involve work on mice and rats, we highlight human studies of P2X7R whenever possible.
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Kan LK, Drill M, Jayakrishnan PC, Sequeira RP, Galea E, Todaro M, Sanfilippo PG, Hunn M, Williams DA, O'Brien TJ, Drummond KJ, Monif M. P2X7 receptor antagonism by AZ10606120 significantly reduced in vitro tumour growth in human glioblastoma. Sci Rep 2023; 13:8435. [PMID: 37225786 DOI: 10.1038/s41598-023-35712-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 05/22/2023] [Indexed: 05/26/2023] Open
Abstract
Glioblastomas are highly aggressive and deadly brain tumours, with a median survival time of 14-18 months post-diagnosis. Current treatment modalities are limited and only modestly increase survival time. Effective therapeutic alternatives are urgently needed. The purinergic P2X7 receptor (P2X7R) is activated within the glioblastoma microenvironment and evidence suggests it contributes to tumour growth. Studies have implicated P2X7R involvement in a range of neoplasms, including glioblastomas, although the roles of P2X7R in the tumour milieu remain unclear. Here, we report a trophic, tumour-promoting role of P2X7R activation in both patient-derived primary glioblastoma cultures and the U251 human glioblastoma cell line, and demonstrate its inhibition reduces tumour growth in vitro. Primary glioblastoma and U251 cell cultures were treated with the specific P2X7R antagonist, AZ10606120 (AZ), for 72 h. The effects of AZ treatment were also compared to cells treated with the current first-line chemotherapeutic drug, temozolomide (TMZ), and a combination of both AZ and TMZ. P2X7R antagonism by AZ significantly depleted glioblastoma cell numbers compared to untreated cells, in both primary glioblastoma and U251 cultures. Notably, AZ treatment was more effective at tumour cell killing than TMZ. No synergistic effect between AZ and TMZ was observed. AZ treatment also significantly increased lactate dehydrogenase release in primary glioblastoma cultures, suggesting AZ-induced cellular cytotoxicity. Our results reveal a trophic role of P2X7R in glioblastoma. Importantly, these data highlight the potential for P2X7R inhibition as a novel and effective alternative therapeutic approach for patients with lethal glioblastomas.
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Affiliation(s)
- Liyen K Kan
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Matthew Drill
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | | | - Richard P Sequeira
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Emily Galea
- Department of Neurosurgery, The Alfred, Melbourne, VIC, Australia
| | - Marian Todaro
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Neurology, The Royal Melbourne Hospital, Melbourne, VIC, Australia
- Department of Neurology, The Alfred, Melbourne, VIC, Australia
| | - Paul G Sanfilippo
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Martin Hunn
- Department of Neurosurgery, The Alfred, Melbourne, VIC, Australia
| | - David A Williams
- Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Terence J O'Brien
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Neurology, The Royal Melbourne Hospital, Melbourne, VIC, Australia
- Department of Neurology, The Alfred, Melbourne, VIC, Australia
| | - Katharine J Drummond
- Department of Neurosurgery, The Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Mastura Monif
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia.
- Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia.
- Department of Neurology, The Royal Melbourne Hospital, Melbourne, VIC, Australia.
- Department of Neurology, The Alfred, Melbourne, VIC, Australia.
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4
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Zhang WJ. Effect of P2X purinergic receptors in tumor progression and as a potential target for anti-tumor therapy. Purinergic Signal 2021; 17:151-162. [PMID: 33420658 PMCID: PMC7954979 DOI: 10.1007/s11302-020-09761-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/10/2020] [Indexed: 02/06/2023] Open
Abstract
The development of tumors is a complex pathological process involving multiple factors, multiple steps, and multiple genes. Their prevention and treatment have always been a difficult problem at present. A large number of studies have proved that the tumor microenvironment plays an important role in the progression of tumors. The tumor microenvironment is the place where tumor cells depend for survival, and it plays an important role in regulating the growth, proliferation, apoptosis, migration, and invasion of tumor cells. P2X purinergic receptors, which depend on the ATP ion channel, can be activated by ATP in the tumor microenvironment, and by mediating tumor cells and related cells (such as immune cells) in the tumor microenvironment. They play an important regulatory role on the effects of the skeleton, membrane fluidity, and intracellular molecular metabolism of tumor cells. Therefore, here, we outlined the biological characteristics of P2X purinergic receptors, described the effect of tumor microenvironment on tumor progression, and discussed the effect of ATP on tumor. Moreover, we explored the role of P2X purinergic receptors in the development of tumors and anti-tumor therapy. These data indicate that P2X purinergic receptors may be used as another potential pharmacological target for tumor prevention and treatment.
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Affiliation(s)
- Wen-Jun Zhang
- Gastrointestinal Surgery, The Second Affiliated Hospital, Nanchang University, Nanchang, 343000, Jiangxi, China.
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5
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Sladkova EA. The Change of Electrical Properties of Blood Corpuscles under in vitro Mechanical Stress. Biophysics (Nagoya-shi) 2020. [DOI: 10.1134/s000635092005019x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Kan LK, Seneviratne S, Drummond KJ, Williams DA, O'Brien TJ, Monif M. P2X7 receptor antagonism inhibits tumour growth in human high-grade gliomas. Purinergic Signal 2020; 16:327-336. [PMID: 32583309 DOI: 10.1007/s11302-020-09705-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 05/21/2020] [Indexed: 12/11/2022] Open
Abstract
Gliomas, the most common primary brain cancer, are highly infiltrative and extremely difficult to treat. Despite advancements, current treatment is limited, with patients surviving for a median of 14-15 months post-diagnosis. Previous research has demonstrated the upregulation of a purinergic receptor, P2X7R, in human gliomas. P2X7R is expressed on both glioma cells and microglia within the glioma microenvironment. It is hypothesized that P2X7R contributes to tumour growth and proliferation via immune-mediated mechanisms involving tumour cells and surrounding microglia. We sought to elucidate the role of P2X7R in a human glioblastoma cell line (U251) and on surgically resected human glioma samples. We treated U251 and human glioma cultures for 72 h with P2X7R antagonists, Brilliant Blue G (BBG), oxidized ATP (oATP) and AZ10606120. Cell counting via fluorescence confocal microscopy was conducted to assess tumour proliferation. We observed no significant reductions in tumour cell numbers following P2X7R antagonism with BBG (20 μM) and oATP (250 μM) in both U251 cells and human glioma samples. Interestingly, there was a significant reduction in tumour cell number in both U251 cells (p = 0.0156) and human glioma samples (p = 0.0476) treated with varying concentrations of AZ10606120. When compared with the conventional chemotherapeutic agent, temozolomide, AZ10606120 was also found to more effectively inhibit tumour proliferation in U251 cells (p < 0.0001). Our pilot results demonstrate a potential trophic role of P2X7R where its inhibition by AZ10606120, a potent antagonist, hinders glioma growth directly or through the inactivation of microglia. This sheds new light on P2X7R as a therapeutic target for human gliomas.
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Affiliation(s)
- Liyen Katrina Kan
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Rd, Melbourne, VIC, 3004, Australia.,Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia
| | | | - Kate J Drummond
- Department of Neurosurgery, Royal Melbourne Hospital, Melbourne, Victoria, Australia
| | - David A Williams
- Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Terence J O'Brien
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Rd, Melbourne, VIC, 3004, Australia.,Department of Neurology, Royal Melbourne Hospital, Melbourne, Victoria, Australia
| | - Mastura Monif
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Rd, Melbourne, VIC, 3004, Australia. .,Department of Physiology, The University of Melbourne, Melbourne, VIC, Australia. .,Department of Neurology, Royal Melbourne Hospital, Melbourne, Victoria, Australia.
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7
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Extracellular Adenine Nucleotides and Adenosine Modulate the Growth and Survival of THP-1 Leukemia Cells. Int J Mol Sci 2020; 21:ijms21124425. [PMID: 32580317 PMCID: PMC7352165 DOI: 10.3390/ijms21124425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 12/26/2022] Open
Abstract
A new approach to improve the effectiveness of acute myeloid leukemia (AML) treatment is to use the properties of purinergic signaling molecules secreted into the bone marrow milieu in response to leukemic cell growth. Therefore, our study aimed to evaluate the effects of extracellular adenine nucleotides and adenosine on the growth and death parameters in the leukemic THP-1 cell line. Cells were exposed to ATP, ADP, AMP, adenosine and nonhydrolyzable analogues of ATP and ADP (ATPγS and ADPβS) in a 1–1000 μM broad concentration range. The basal mRNA expression of the P1 and P2 receptors was evaluated by real-time PCR. Changes in the processes of cell growth and death were assessed by flow cytometry analysis of proliferation, cell cycle and apoptosis. Chemotaxis toward stromal cell-derived factor-1 (SDF-1) was performed using the modified Boyden chamber assay, and chemokine receptor type 4 (CXCR4) surface expression was quantified by flow cytometry. We indicated several antileukemic actions. High micromolar concentrations (100–1000 μM) of extracellular adenine nucleotides and adenosine inhibit the growth of cells by arresting the cell cycle and/or inducing apoptosis. ATP is characterized by the highest potency and widest range of effects, and is responsible for the cell cycle arrest and the apoptosis induction. Compared to ATP, the effect of ADP is slightly weaker. Adenosine mostly has a cytotoxic effect, with the induction of apoptosis. The last studied nucleotide, AMP, demonstrated only a weak cytotoxic effect without affecting the cell cycle. In addition, cell migration towards SDF-1 was inhibited by low micromolar concentrations (10 μM). One of the reasons for this action of ATPγS and adenosine was a reduction in CXCR4 surface expression, but this only partially explains the mechanism of antimigratory action. In summary, extracellular adenine nucleotides and adenosine inhibit THP-1 cell growth, cause death of cells and modulate the functioning of the SDF-1/CXCR4 axis. Thus, they negatively affect the processes that are responsible for the progression of AML and the difficulties in AML treatment.
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Filippin KJ, de Souza KFS, de Araujo Júnior RT, Torquato HFV, Dias DA, Parisotto EB, Ferreira AT, Paredes-Gamero EJ. Involvement of P2 receptors in hematopoiesis and hematopoietic disorders, and as pharmacological targets. Purinergic Signal 2020; 16:1-15. [PMID: 31863258 PMCID: PMC7166233 DOI: 10.1007/s11302-019-09684-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/12/2019] [Indexed: 12/11/2022] Open
Abstract
Several reports have shown the presence of P2 receptors in hematopoietic stem cells (HSCs). These receptors are activated by extracellular nucleotides released from different sources. In the hematopoietic niche, the release of purines and pyrimidines in the milieu by lytic and nonlytic mechanisms has been described. The expression of P2 receptors from HSCs until maturity is still intriguing scientists. Several reports have shown the participation of P2 receptors in events associated with modulation of the immune system, but their participation in other physiological processes is under investigation. The presence of P2 receptors in HSCs and their ability to modulate this population have awakened interest in exploring the involvement of P2 receptors in hematopoiesis and their participation in hematopoietic disorders. Among the P2 receptors, the receptor P2X7 is of particular interest, because of its different roles in hematopoietic cells (e.g., infection, inflammation, cell death and survival, leukemias and lymphomas), making the P2X7 receptor a promising pharmacological target. Additionally, the role of P2Y12 receptor in platelet activation has been well-documented and is the main example of the importance of the pharmacological modulation of P2 receptor activity. In this review, we focus on the role of P2 receptors in the hematopoietic system, addressing these receptors as potential pharmacological targets.
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Affiliation(s)
- Kelly Juliana Filippin
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, 79070-900, Brazil
| | - Kamylla F S de Souza
- Departamento de Bioquímica, Universidade Federal de São Paulo, R. Três de Maio 100, São Paulo, SP, 04044-020, Brazil
| | | | - Heron Fernandes Vieira Torquato
- Departamento de Bioquímica, Universidade Federal de São Paulo, R. Três de Maio 100, São Paulo, SP, 04044-020, Brazil
- Universidade Braz Cubas, Av. Francisco Rodrigues Filho 1233, Mogi das Cruzes, SP, 08773-380, Brazil
| | - Dhébora Albuquerque Dias
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, 79070-900, Brazil
| | - Eduardo Benedetti Parisotto
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, 79070-900, Brazil
| | - Alice Teixeira Ferreira
- Departamento de Biofísica, Universidade Federal de São Paulo, R. Botucatu 862, São Paulo, SP, 04023-062, Brazil.
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição (FACFAN), Laboratório de Biologia Molecular e Culturas Celulares, Av. Costa e Silva, s/n Bairro Universitário, Campo Grande, MS, CEP: 79070-900, Brazil.
| | - Edgar J Paredes-Gamero
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, 79070-900, Brazil.
- Departamento de Bioquímica, Universidade Federal de São Paulo, R. Três de Maio 100, São Paulo, SP, 04044-020, Brazil.
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição (FACFAN), Laboratório de Biologia Molecular e Culturas Celulares, Av. Costa e Silva, s/n Bairro Universitário, Campo Grande, MS, CEP: 79070-900, Brazil.
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9
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The role of microglia and P2X7 receptors in gliomas. J Neuroimmunol 2019; 332:138-146. [PMID: 31031209 DOI: 10.1016/j.jneuroim.2019.04.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 04/18/2019] [Accepted: 04/18/2019] [Indexed: 02/06/2023]
Abstract
Gliomas are the most prevalent tumours of the central nervous system and present with high morbidity and mortality. The most common and most aggressive form of glioma is glioblastoma multiforme, of which patients have a median survival time of only 12 to 15 months. Current treatment options are limited and have a small impact on clinical outcome and prognosis. There is accumulating evidence that microglia, the immunocompetent cells of the central nervous system, and the purinergic P2X7 receptor (P2X7R) may contribute to tumour progression and pathology. Importantly, P2X7R on both tumour cells and infiltrating microglia is overexpressed in animal and human glioma cultures. Factors released by glioma cells and P2X7R activation recruit microglia into the largely immunosuppressive tumour microenvironment where they have been demonstrated to contribute to either tumour proliferation or tumour suppression. It is likely that P2X7R mediates a range of microglia effector functions in the glioma setting, potentially increasing tumour growth and proliferation. This review evaluates current evidence on the roles of microglia and P2X7R in glioma pathogenesis. Understanding the nature, mechanisms and outcomes of microglia and P2X7R activation in gliomas is necessary for the development of more therapies with increased efficacy and specificity.
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10
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Salvestrini V, Orecchioni S, Talarico G, Reggiani F, Mazzetti C, Bertolini F, Orioli E, Adinolfi E, Di Virgilio F, Pezzi A, Cavo M, Lemoli RM, Curti A. Extracellular ATP induces apoptosis through P2X7R activation in acute myeloid leukemia cells but not in normal hematopoietic stem cells. Oncotarget 2018; 8:5895-5908. [PMID: 27980223 PMCID: PMC5351599 DOI: 10.18632/oncotarget.13927] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/25/2016] [Indexed: 11/25/2022] Open
Abstract
Recent studies have shown that high ATP levels exhibit direct cytotoxic effects on several cancer cells types. Among the receptors engaged by ATP, P2X7R is the most consistently expressed by tumors. P2X7R is an ATP-gated ion channel that could drive the opening of a non-selective pore, triggering cell-death signal. We previously demonstrated that acute myeloid leukemia (AML) cells express high level of P2X7R. Here, we show that P2X7R activation with high dose ATP induces AML blast cells apoptosis. Moreover, P2X7R is also expressed on leukemic stem/progenitor cells (LSCs) which are sensitive to ATP-mediated cytotoxicity. Conversely, this cytotoxic effect was not observed on normal hematopoietic stem/progenitor cells (HSCs). Notably, the antileukemic activity of ATP was also observed in presence of bone marrow stromal cells and its addition to the culture medium enhanced cytosine arabinoside cytotoxicity despite stroma-induced chemoresistance. Xenotransplant experiments confirmed ATP antineoplastic activity in vivo.Overall, our results demonstrate that P2X7R stimulation by ATP induced a therapeutic response in AML at the LSC level while the normal stem cell compartment was not affected. These results provide evidence that ATP would be promising for developing innovative therapy for AML.
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Affiliation(s)
- Valentina Salvestrini
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | | | | | | | - Cristina Mazzetti
- Department Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | | | - Elisa Orioli
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Elena Adinolfi
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Francesco Di Virgilio
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Annalisa Pezzi
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Michele Cavo
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Roberto M Lemoli
- Clinic of Hematology, Department of Internal Medicine (DiMI), University of Genoa, Genoa, Italy
| | - Antonio Curti
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
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11
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Wang J, Liu S, Nie Y, Wu B, Wu Q, Song M, Tang M, Xiao L, Xu P, Tan X, Zhang L, Li G, Liang S, Zhang C. Activation of P2X7 receptors decreases the proliferation of murine luteal cells. Reprod Fertil Dev 2017; 27:1262-71. [PMID: 25782073 DOI: 10.1071/rd14381] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 02/09/2015] [Indexed: 12/14/2022] Open
Abstract
Extracellular ATP regulates cellular function in an autocrine or paracrine manner through activating purinergic signalling. Studies have shown that purinergic receptors were expressed in mammalian ovaries and they have been proposed as an intra-ovarian regulatory mechanism. P2X7 was expressed in porcine ovarian theca cells and murine and human ovarian surface epithelium and is involved in ATP-induced apoptotic cell death. However, the role of P2X7 in corpus luteum is still unclear. The aim of this study was to investigate the role of ATP signalling in murine luteal cells and the possible mechanism(s) involved. We found that P2X7 was highly expressed in murine small luteal cells. The agonists of P2X7, ATP and BzATP, inhibited the proliferation of luteal cells. P2X7 antagonist BBG reversed the inhibition induced by ATP and BzATP. Further studies showed that ATP and BzATP inhibited the expression of cell cycle regulators cyclinD2 and cyclinE2. ATP and BzATP also inhibited the p38-mitogen-activated protein kinase (MAPK) signalling pathway. These results reveal that P2X7 receptor activation is involved in corpus luteum formation and function.
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Affiliation(s)
- Jing Wang
- Department of Microbiology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Shuangmei Liu
- Department of Physiology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Yijun Nie
- The First Affiliated Hospital, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Bing Wu
- Department of Physiology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Qin Wu
- Department of Physiology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Miaomiao Song
- Department of Physiology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Min Tang
- Department of Cell Biology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Li Xiao
- Department of Cell Biology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Ping Xu
- School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Ximin Tan
- School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Luyin Zhang
- School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Gang Li
- Department of Cell Biology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Shangdong Liang
- Department of Physiology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
| | - Chunping Zhang
- Department of Cell Biology, School of Medicine, Nanchang University, #461 Bayi Avenue, Nanchang, Jiangxi 330006, People's Republic of China
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Emerging role of P2X7 receptors in CNS health and disease. Ageing Res Rev 2015; 24:328-42. [PMID: 26478005 DOI: 10.1016/j.arr.2015.10.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 10/05/2015] [Indexed: 12/11/2022]
Abstract
Purinergic signalling in the brain is becoming an important focus in the study of CNS health and disease. Various purinergic receptors are found to be present in different brain cells in varying extent, which get activated upon binding of ATP or its analogues. Conventionally, ATP was considered only as a major metabolic fuel of the cell but its recognition as a neurotransmitter in early 1970s, brought meaningful insights in neuron glia crosstalk, participating in various physiological functions in the brain. P2X7R, a member of ligand gated purinergic receptor (P2X) family, is gaining attention in the field of neuroscience because of its emerging role in broad spectrum of ageing and age related neurological disorders. The aim of this review is to provide an overview about the structure and function of P2X7R highlighting its unique features which distinguish it from the other members of its family. This review critically analyzes the literature mentioning the details about the agonist and antagonist of the P2X7R. It also emphasizes the advancements in understanding the dual role of P2X7R in brain development and disorders inviting meaningful insights about its involvement in Alzheimer's disease, Huntington's disease, Multiple Sclerosis, Neuropathic pain, Spinal Cord Injury and NeuroAIDS. Exploring the roles of P2X7R in detail is critical to identify its therapeutic potential in the treatment of acute and chronic neurodegenerative diseases. Moreover, this review also helps to raise more interest in the neurobiology of the purinergic receptors and thus providing new avenues for future research.
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Burnstock G, Di Virgilio F. Purinergic signalling and cancer. Purinergic Signal 2014; 9:491-540. [PMID: 23797685 DOI: 10.1007/s11302-013-9372-5] [Citation(s) in RCA: 234] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Accepted: 06/06/2013] [Indexed: 01/24/2023] Open
Abstract
Receptors for extracellular nucleotides are widely expressed by mammalian cells. They mediate a large array of responses ranging from growth stimulation to apoptosis, from chemotaxis to cell differentiation and from nociception to cytokine release, as well as neurotransmission. Pharma industry is involved in the development and clinical testing of drugs selectively targeting the different P1 nucleoside and P2 nucleotide receptor subtypes. As described in detail in the present review, P2 receptors are expressed by all tumours, in some cases to a very high level. Activation or inhibition of selected P2 receptor subtypes brings about cancer cell death or growth inhibition. The field has been largely neglected by current research in oncology, yet the evidence presented in this review, most of which is based on in vitro studies, although with a limited amount from in vivo experiments and human studies, warrants further efforts to explore the therapeutic potential of purinoceptor targeting in cancer.
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Glass C, Wuertzer C, Cui X, Bi Y, Davuluri R, Xiao YY, Wilson M, Owens K, Zhang Y, Perkins A. Global Identification of EVI1 Target Genes in Acute Myeloid Leukemia. PLoS One 2013; 8:e67134. [PMID: 23826213 PMCID: PMC3694976 DOI: 10.1371/journal.pone.0067134] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 05/19/2013] [Indexed: 12/20/2022] Open
Abstract
The ecotropic virus integration site 1 (EVI1) transcription factor is associated with human myeloid malignancy of poor prognosis and is overexpressed in 8-10% of adult AML and strikingly up to 27% of pediatric MLL-rearranged leukemias. For the first time, we report comprehensive genomewide EVI1 binding and whole transcriptome gene deregulation in leukemic cells using a combination of ChIP-Seq and RNA-Seq expression profiling. We found disruption of terminal myeloid differentiation and cell cycle regulation to be prominent in EVI-induced leukemogenesis. Specifically, we identified EVI1 directly binds to and downregulates the master myeloid differentiation gene Cebpe and several of its downstream gene targets critical for terminal myeloid differentiation. We also found EVI1 binds to and downregulates Serpinb2 as well as numerous genes involved in the Jak-Stat signaling pathway. Finally, we identified decreased expression of several ATP-dependent P2X purinoreceptors genes involved in apoptosis mechanisms. These findings provide a foundation for future study of potential therapeutic gene targets for EVI1-induced leukemia.
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Affiliation(s)
- Carolyn Glass
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Charles Wuertzer
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Xiaohui Cui
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Yingtao Bi
- Molecular and Cellular Oncogenesis Program, Center for Systems and Computational Biology The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Ramana Davuluri
- Molecular and Cellular Oncogenesis Program, Center for Systems and Computational Biology The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Ying-Yi Xiao
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Michael Wilson
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Kristina Owens
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Yi Zhang
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Archibald Perkins
- Department of Pathology and Lab Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
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Bian S, Sun X, Bai A, Zhang C, Li L, Enjyoji K, Junger WG, Robson SC, Wu Y. P2X7 integrates PI3K/AKT and AMPK-PRAS40-mTOR signaling pathways to mediate tumor cell death. PLoS One 2013; 8:e60184. [PMID: 23565201 PMCID: PMC3615040 DOI: 10.1371/journal.pone.0060184] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 02/22/2013] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Extracellular adenosine triphosphate (ATP) functions as a novel danger signal that boosts antitumor immunity and can also directly kill tumor cells. We have previously reported that chronic exposure of tumor cells to ATP provokes P2X7-mediated tumor cell death, by as yet incompletely defined molecular mechanisms. METHODOLOGY/PRINCIPAL FINDINGS Here, we show that acute exposure of tumor cells to ATP results in rapid cytotoxic effects impacting several aspects of cell growth/survival, leading to inhibition of tumor growth in vitro and in vivo. Using agonist and antagonist studies together with generation of P2X7 deficient tumor cell lines by lentiviral shRNA delivery system, we confirm P2X7 to be the central control node transmitting extracellular ATP signals. We identify that downstream intracellular signaling regulatory networks implicate two signaling pathways: the known P2X7-PI3K/AKT axis and remarkably a novel P2X7-AMPK-PRAS40-mTOR axis. When exposed to high levels of extracellular ATP, these two signaling axes perturb the balance between growth and autophagy, thereby promoting tumor cell death. CONCLUSIONS Our study defines novel molecular mechanisms underpinning the antitumor actions of P2X7 and provides a further rationale for purine-based drugs in targeted cancer therapy.
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Affiliation(s)
- Shu Bian
- Department of Gastroenterology, Provincial Hospital Affiliated to Shandong University, Jinan, People’s Republic of China
- Department of Medicine, Transplant Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Xiaofeng Sun
- Department of Medicine, Transplant Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Aiping Bai
- Department of Medicine, Transplant Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Chunqing Zhang
- Department of Gastroenterology, Provincial Hospital Affiliated to Shandong University, Jinan, People’s Republic of China
| | - Linglin Li
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Keiichi Enjyoji
- Department of Medicine, Transplant Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Wolfgang G. Junger
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Simon C. Robson
- Department of Medicine, Transplant Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Yan Wu
- Department of Medicine, Transplant Institute, Harvard Medical School, Boston, Massachusetts, United States of America
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Whiteside TL, Mandapathil M, Schuler P. The role of the adenosinergic pathway in immunosuppression mediated by human regulatory T cells (Treg). Curr Med Chem 2012; 18:5217-23. [PMID: 22087822 DOI: 10.2174/092986711798184334] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 10/01/2011] [Indexed: 12/30/2022]
Abstract
Tumor-induced dysfunction of immune cells is a common problem in cancer. Tumors induce immune suppression by many different mechanisms, including accumulation of regulatory T cells (Treg). Adaptive Treg (Tr1) generated in the tumor microenvironment express CD39 and CD73 ectonucleotidases, produce adenosine and are COX2+PGE2+. Adenosine and PGE2 produced by Tr1 or tumor cells bind to their respective receptors on the surface of T effector cells (Teff) and cooperate in up-regulating cytosolic 3'5'-cAMP levels utilizing adenylyl cyclase isoform 7 (AC-7). In Teff, increased cAMP mediates suppression of anti-tumor functions. Treg, in contrast to Teff, seem to require high cAMP levels for mediating suppression. This differential requirement of Treg and Teff for cAMP offers an opportunity for pharmacologic interventions using selected inhibitors of the adenosine/PGE2 pathways. Blocking of adenosine/PGE2 production by Tr1 or blocking binding of these factors to their receptors on T cells or inhibition of cAMP synthesis in Teff all represent novel therapeutic strategies that used in combination with conventional therapies could restore anti-tumor functions of Teff . At the same time, these inhibitors could disarm Tr1 cells by depriving them of the factors promoting their generation and activity or by down-regulating 3'5'-cAMP levels. Thus, the pharmacologic control of Treg-Teff interactions offers a novel strategy for restoration of anti-tumor Teff functions and silencing of Treg. Used in conjunction with anti-cancer drugs or with immune therapies, this strategy has a potential to improve therapeutic effects by preventing or reversing tumor-induced immune suppression.
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Affiliation(s)
- T L Whiteside
- University of Pittsburgh Cancer Institute, Research Pavilion at the Hillman Cancer Center, 5117 Centre Avenue, Suite 1.27, Pittsburgh, PA 15213-1863, USA.
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Flanaghan JR, Roome SJ. The impact of commercially available purinergic ligands on purinergic signalling research. Purinergic Signal 2011; 8:81-9. [PMID: 22038574 DOI: 10.1007/s11302-011-9269-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 10/19/2011] [Indexed: 11/26/2022] Open
Abstract
Due to the extremely wide-spread expression of purinergic receptors, purinergic signalling has been implicated in numerous physiological and pathophysiological areas. To better understand the involvement of purinergic receptors in such areas, the researcher's requirement for diverse and varied purinergic receptor ligands has greatly increased. This has generated increased commercial opportunities for life science suppliers, and ultimately, has led to a rapid expansion in the number of commercially available purinergic receptor ligands. The wide-spread availability of ligands to researchers has greatly benefited the scientific community, nurturing the rapid and continued expansion of the purinergic signalling field.
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Affiliation(s)
- J R Flanaghan
- Ascent Scientific Ltd (UK), Unit 3 Avon Riverside Estate, Victoria Road, Avonmouth Bristol, BS11 9DB, UK,
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Mandapathil M, Whiteside TL. Targeting human inducible regulatory T cells (Tr1) in patients with cancer: blocking of adenosine-prostaglandin E₂ cooperation. Expert Opin Biol Ther 2011; 11:1203-14. [PMID: 21702720 PMCID: PMC3149765 DOI: 10.1517/14712598.2011.581225] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Emerging data suggest that human inducible regulatory T cells (Tr1) produce adenosine and prostaglandin E(2) and that these factors cooperate in mediating immune suppression. AREAS COVERED Human Tr1 present in human tumors or blood of cancer patients express ectonucleotidases, CD39 and/or CD73, hydrolyze ATP to adenosine and are COX-2 positive. Expression of CD39 and/or CD73 on human tumors favors expansion and suppressor functions of Tr1. Adenosine and PGE(2) signal via adenosine 2A receptor (A(2A)R) and prostaglandin E(2) receptor 2 (EP(2)R) expressed on effector T (Teff) cells, suppressing their anti-tumor functions by a common mechanism involving upregulation of cytosolic cAMP levels and protein kinase A (PKA) type I activation. The frequency and activity of circulating CD4(+)CD39(+) and CD4(+)COX-2(+) Treg subsets increase in advanced disease and also following oncologic therapies. EXPERT OPINION Pharmacologic blocking of adenosine-PGE(2) collaboration provides a clinically-feasible strategy for disarming of Treg. Used in conjunction with conventional anti-cancer drugs or immune interventions, pharmacologic inhibitors could improve outcome of oncologic therapies.
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Affiliation(s)
- Magis Mandapathil
- University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pathology, 5117 Centre Avenue, Suite 1.27, Pittsburgh, PA 15213, USA.
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Tafani M, Schito L, Pellegrini L, Villanova L, Marfe G, Anwar T, Rosa R, Indelicato M, Fini M, Pucci B, Russo MA. Hypoxia-increased RAGE and P2X7R expression regulates tumor cell invasion through phosphorylation of Erk1/2 and Akt and nuclear translocation of NF-{kappa}B. Carcinogenesis 2011; 32:1167-75. [PMID: 21642357 DOI: 10.1093/carcin/bgr101] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The role of hypoxia in regulating tumor progression is still controversial. Here, we demonstrate that, similarly to what previously observed by us in human prostate and breast tumor samples, hypoxia increases expression of the receptor for advanced glycation end products (RAGE) and the purinergic receptor P2X7 (P2X7R). The role of hypoxia was shown by the fact that hypoxia-inducible factor (HIF)-1α silencing downregulated RAGE and P2X7R protein levels as well as nuclear factor-kappaB (NF-κB) expression. In contrast, NF-κB silencing reduced P2X7R expression without affecting RAGE protein levels or nuclear accumulation of HIF-1α. Treatment of hypoxic tumor cells with HMGB1 and BzATP ligands, respectively, of RAGE and P2X7R, activated a signaling pathway that, through Akt and Erk phosphorylation, determines nuclear accumulation of NF-κB and increases cell invasion. Inhibition of Akt by SH5 and Erk by INH1 prevented both nuclear translocation of NF-κB and cell invasion. Moreover, silencing RAGE and P2X7R abolished nuclear accumulation of NF-κB as well as cell invasion without affecting HIF-1α stabilization. Once in the nucleus, NF-κB would contribute to cell survival and invasion under hypoxia, by maintaining RAGE and P2X7R expression levels and matrix metalloproteinases 2 and 9 synthesis. These results show that, hypoxia can upregulate expression levels of membrane receptors that, by binding extracellular molecules eventually released by necrotic cells, contribute to the increased invasiveness of transformed tumor cells. Moreover, these observations strengthen our working hypothesis that upregulation of damage-associated molecular patterns receptors by HIF-1α represents the crucial event bridging hypoxia and inflammation in obtaining the malignant phenotype.
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Affiliation(s)
- Marco Tafani
- Department of Experimental Medicine, Sapienza University, Rome, Italy.
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