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Marin JJG, Serrano MA, Herraez E, Lozano E, Ortiz-Rivero S, Perez-Silva L, Reviejo M, Briz O. Impact of genetic variants in the solute carrier ( SLC) genes encoding drug uptake transporters on the response to anticancer chemotherapy. CANCER DRUG RESISTANCE (ALHAMBRA, CALIF.) 2024; 7:27. [PMID: 39143954 PMCID: PMC11322974 DOI: 10.20517/cdr.2024.42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 06/14/2024] [Accepted: 06/20/2024] [Indexed: 08/16/2024]
Abstract
Cancer drug resistance constitutes a severe limitation for the satisfactory outcome of these patients. This is a complex problem due to the co-existence in cancer cells of multiple and synergistic mechanisms of chemoresistance (MOC). These mechanisms are accounted for by the expression of a set of genes included in the so-called resistome, whose effectiveness often leads to a lack of response to pharmacological treatment. Additionally, genetic variants affecting these genes further increase the complexity of the question. This review focuses on a set of genes encoding members of the transportome involved in drug uptake, which have been classified into the MOC-1A subgroup of the resistome. These proteins belong to the solute carrier (SLC) superfamily. More precisely, we have considered here several members of families SLC2, SLC7, SLC19, SLC22, SLCO, SLC28, SLC29, SLC31, SLC46, and SLC47 due to the impact of their expression and genetic variants in anticancer drug uptake by tumor cells or, in some cases, general bioavailability. Changes in their expression levels and the appearance of genetic variants can contribute to the Darwinian selection of more resistant clones and, hence, to the development of a more malignant phenotype. Accordingly, to address this issue in future personalized medicine, it is necessary to characterize both changes in resistome genes that can affect their function. It is also essential to consider the time-dependent dimension of these features, as the genetic expression and the appearance of genetic variants can change during tumor progression and in response to treatment.
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Affiliation(s)
- Jose J. G. Marin
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBEREHD), Carlos III National Institute of Health, Madrid 28029, Spain
| | - Maria A. Serrano
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBEREHD), Carlos III National Institute of Health, Madrid 28029, Spain
| | - Elisa Herraez
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBEREHD), Carlos III National Institute of Health, Madrid 28029, Spain
| | - Elisa Lozano
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBEREHD), Carlos III National Institute of Health, Madrid 28029, Spain
| | - Sara Ortiz-Rivero
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBEREHD), Carlos III National Institute of Health, Madrid 28029, Spain
| | - Laura Perez-Silva
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
| | - Maria Reviejo
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBEREHD), Carlos III National Institute of Health, Madrid 28029, Spain
| | - Oscar Briz
- Experimental Hepatology and Drug Targeting (HEVEPHARM), University of Salamanca, Institute for Biomedical Research of Salamanca (IBSAL), Salamanca 37007, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBEREHD), Carlos III National Institute of Health, Madrid 28029, Spain
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2
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Hruba L, Das V, Hajduch M, Dzubak P. Nucleoside-based anticancer drugs: Mechanism of action and drug resistance. Biochem Pharmacol 2023; 215:115741. [PMID: 37567317 DOI: 10.1016/j.bcp.2023.115741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/06/2023] [Accepted: 08/08/2023] [Indexed: 08/13/2023]
Abstract
Nucleoside-based drugs, recognized as purine or pyrimidine analogs, have been potent therapeutic agents since their introduction in 1950, deployed widely in the treatment of diverse diseases such as cancers, myelodysplastic syndromes, multiple sclerosis, and viral infections. These antimetabolites establish complex interactions with cellular molecular constituents, primarily via activation of phosphorylation cascades leading to consequential interactions with nucleic acids. However, the therapeutic efficacy of these agents is frequently compromised by the development of drug resistance, a continually emerging challenge in their clinical application. This comprehensive review explores the mechanisms of resistance to nucleoside-based drugs, encompassing a wide spectrum of phenomena from alterations in membrane transporters and activating kinases to changes in drug elimination strategies and DNA damage repair mechanisms. The critical analysis in this review underlines complex interactions of drug and cell and also guides towards novel therapeutic strategies to counteract resistance. The development of targeted therapies, novel nucleoside analogs, and synergistic drug combinations are promising approaches to restore tumor sensitivity and improve patient outcomes.
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Affiliation(s)
- Lenka Hruba
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University in Olomouc, Olomouc, Czech Republic
| | - Viswanath Das
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University in Olomouc, Olomouc, Czech Republic
| | - Marian Hajduch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University in Olomouc, Olomouc, Czech Republic; Laboratory of Experimental Medicine, University Hospital, Olomouc 779 00, Czech Republic
| | - Petr Dzubak
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University in Olomouc, Olomouc, Czech Republic; Laboratory of Experimental Medicine, University Hospital, Olomouc 779 00, Czech Republic.
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3
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Nucleoside transporters and immunosuppressive adenosine signaling in the tumor microenvironment: Potential therapeutic opportunities. Pharmacol Ther 2022; 240:108300. [PMID: 36283452 DOI: 10.1016/j.pharmthera.2022.108300] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 10/17/2022] [Accepted: 10/19/2022] [Indexed: 11/30/2022]
Abstract
Adenosine compartmentalization has a profound impact on immune cell function by regulating adenosine localization and, therefore, extracellular signaling capabilities, which suppresses immune cell function in the tumor microenvironment. Nucleoside transporters, responsible for the translocation and cellular compartmentalization of hydrophilic adenosine, represent an understudied yet crucial component of adenosine disposition in the tumor microenvironment. In this review article, we will summarize what is known regarding nucleoside transporter's function within the purinome in relation to currently devised points of intervention (i.e., ectonucleotidases, adenosine receptors) for cancer immunotherapy, alterations in nucleoside transporter expression reported in cancer, and potential avenues for targeting of nucleoside transporters for the desired modulation of adenosine compartmentalization and action. Further, we put forward that nucleoside transporters are an unexplored therapeutic opportunity, and modulation of nucleoside transport processes could attenuate the pathogenic buildup of immunosuppressive adenosine in solid tumors, particularly those enriched with nucleoside transport proteins.
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Levin M, Stark M, Ofran Y, Assaraf YG. Deciphering molecular mechanisms underlying chemoresistance in relapsed AML patients: towards precision medicine overcoming drug resistance. Cancer Cell Int 2021; 21:53. [PMID: 33446189 PMCID: PMC7809753 DOI: 10.1186/s12935-021-01746-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 01/02/2021] [Indexed: 12/13/2022] Open
Abstract
Background Acute myeloid leukemia (AML) remains a devastating disease with a 5-year survival rate of less than 30%. AML treatment has undergone significant changes in recent years, incorporating novel targeted therapies along with improvements in allogeneic bone marrow transplantation techniques. However, the standard of care remains cytarabine and anthracyclines, and the primary hindrance towards curative treatment is the frequent emergence of intrinsic and acquired anticancer drug resistance. In this respect, patients presenting with chemoresistant AML face dismal prognosis even with most advanced therapies. Herein, we aimed to explore the potential implementation of the characterization of chemoresistance mechanisms in individual AML patients towards efficacious personalized medicine. Methods Towards the identification of tailored treatments for individual patients, we herein present the cases of relapsed AML patients, and compare them to patients displaying durable remissions following the same chemotherapeutic induction treatment. We quantified the expression levels of specific genes mediating drug transport and metabolism, nucleotide biosynthesis, and apoptosis, in order to decipher the molecular mechanisms underlying intrinsic and/or acquired chemoresistance modalities in relapsed patients. This was achieved by real-time PCR using patient cDNA, and could be readily implemented in the clinical setting. Results This analysis revealed pre-existing differences in gene expression levels between the relapsed patients and patients with lasting remissions, as well as drug-induced alterations at different relapse stages compared to diagnosis. Each of the relapsed patients displayed unique chemoresistance mechanisms following similar treatment protocols, which could have been missed in a large study aimed at identifying common drug resistance determinants. Conclusions Our findings emphasize the need for standardized evaluation of key drug transport and metabolism genes as an integral component of routine AML management, thereby allowing for the selection of treatments of choice for individual patients. This approach could facilitate the design of efficacious personalized treatment regimens, thereby reducing relapse rates of therapy refractory disease.
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Affiliation(s)
- May Levin
- The Fred Wyszkowski Cancer Research Laboratory, Dept. of Biology, Technion-Israel Institute of Technology, 3200003, Haifa, Israel
| | - Michal Stark
- The Fred Wyszkowski Cancer Research Laboratory, Dept. of Biology, Technion-Israel Institute of Technology, 3200003, Haifa, Israel
| | - Yishai Ofran
- Department of Hematology and Bone Marrow Transplantation, Rambam Health Care Campus, Haifa, Israel.
| | - Yehuda G Assaraf
- The Fred Wyszkowski Cancer Research Laboratory, Dept. of Biology, Technion-Israel Institute of Technology, 3200003, Haifa, Israel.
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Al-Abdulla R, Perez-Silva L, Abete L, Romero MR, Briz O, Marin JJG. Unraveling ‘The Cancer Genome Atlas’ information on the role of SLC transporters in anticancer drug uptake. Expert Rev Clin Pharmacol 2019; 12:329-341. [DOI: 10.1080/17512433.2019.1581605] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Ruba Al-Abdulla
- Experimental Hepatology and Drug Targeting (HEVEFARM), University of Salamanca, IBSAL, Salamanca, Spain
| | - Laura Perez-Silva
- Experimental Hepatology and Drug Targeting (HEVEFARM), University of Salamanca, IBSAL, Salamanca, Spain
| | - Lorena Abete
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Marta R. Romero
- Experimental Hepatology and Drug Targeting (HEVEFARM), University of Salamanca, IBSAL, Salamanca, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
| | - Oscar Briz
- Experimental Hepatology and Drug Targeting (HEVEFARM), University of Salamanca, IBSAL, Salamanca, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
| | - Jose J. G. Marin
- Experimental Hepatology and Drug Targeting (HEVEFARM), University of Salamanca, IBSAL, Salamanca, Spain
- Center for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
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Lucafò M, Franca R, Selvestrel D, Curci D, Pugnetti L, Decorti G, Stocco G. Pharmacogenetics of treatments for inflammatory bowel disease. Expert Opin Drug Metab Toxicol 2018; 14:1209-1223. [PMID: 30465611 DOI: 10.1080/17425255.2018.1551876] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Inflammatory bowel disease is a chronic inflammation of the gut whose pathogenesis is still unclear. Although no curative therapy is currently available, a number of drugs are used in induction and maintenance therapy; however, for most of these drugs, a high inter-individual variability in response is observed. Among the factors of this variability, genetics plays an important role. Areas covered: This review summarizes the results of pharmacogenetic studies, considering the most important drugs used and in particular aminosalycilates, glucocorticoids, thiopurines, monoclonal antibodies and thalidomide. Most studies used a candidate gene approach, even if significant breakthroughs have been obtained recently from applying genome-wide studies. When available, also investigations considering epigenetics and pharmacogenetic dosing guidelines have been included. Expert opinion: Only for thiopurines, genetic markers identified as predictors of efficacy or adverse events have allowed the development of dosing guidelines. For the other drugs, encouraging results are available and great expectations rely on the study of epigenetics and integration with pharmacokinetic information, especially useful for biologics. However, to improve therapy of IBD patients with these drugs, for implementation in the clinics of pharmacogenetics, informatic clinical decision support systems and training about pharmacogenetics of health providers are needed.
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Affiliation(s)
- Marianna Lucafò
- a Experimental and Clinical Pharmacology Unit , National Cancer Institute - Centro di Riferimento Oncologico , Aviano , Italy.,b Institute for Maternal and Child Health IRCCS Burlo Garofolo , Diagnostics Department Trieste , Italy
| | - Raffaella Franca
- b Institute for Maternal and Child Health IRCCS Burlo Garofolo , Diagnostics Department Trieste , Italy.,c Department of Medical, Surgical and Health Sciences , University of Trieste , Trieste , Italy
| | - Davide Selvestrel
- d PhD School in Science of Reproduction and Development , University of Trieste , Trieste , Italy
| | - Debora Curci
- d PhD School in Science of Reproduction and Development , University of Trieste , Trieste , Italy
| | - Letizia Pugnetti
- d PhD School in Science of Reproduction and Development , University of Trieste , Trieste , Italy
| | - Giuliana Decorti
- b Institute for Maternal and Child Health IRCCS Burlo Garofolo , Diagnostics Department Trieste , Italy.,c Department of Medical, Surgical and Health Sciences , University of Trieste , Trieste , Italy
| | - Gabriele Stocco
- e Department of Life Sciences , University of Trieste , Trieste , Italy
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Lim SZ, Chua EW. Revisiting the Role of Thiopurines in Inflammatory Bowel Disease Through Pharmacogenomics and Use of Novel Methods for Therapeutic Drug Monitoring. Front Pharmacol 2018; 9:1107. [PMID: 30349479 PMCID: PMC6186994 DOI: 10.3389/fphar.2018.01107] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 09/10/2018] [Indexed: 12/12/2022] Open
Abstract
Azathioprine and 6-mercaptopurine, often referred to as thiopurine compounds, are commonly used in the management of inflammatory bowel disease. However, patients receiving these drugs are prone to developing adverse drug reactions or therapeutic resistance. Achieving predefined levels of two major thiopurine metabolites, 6-thioguanine nucleotides and 6-methylmercaptopurine, is a long-standing clinical practice in ensuring therapeutic efficacy; however, their correlation with treatment response is sometimes unclear. Various genetic markers have also been used to aid the identification of patients who are thiopurine-sensitive or refractory. The recent discovery of novel Asian-specific DNA variants, namely those in the NUDT15 gene, and their link to thiopurine toxicity, have led clinicians and scientists to revisit the utility of Caucasian biomarkers for Asian individuals with inflammatory bowel disease. In this review, we explore the limitations associated with the current methods used for therapeutic monitoring of thiopurine metabolites and how the recent discovery of ethnicity-specific genetic markers can complement thiopurine metabolites measurement in formulating a strategy for more accurate prediction of thiopurine response. We also discuss the challenges in thiopurine therapy, alongside the current strategies used in patients with reduced thiopurine response. The review is concluded with suggestions for future work aiming at using a more comprehensive approach to optimize the efficacy of thiopurine compounds in inflammatory bowel disease.
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Affiliation(s)
| | - Eng Wee Chua
- Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
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8
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Tsesmetzis N, Paulin CBJ, Rudd SG, Herold N. Nucleobase and Nucleoside Analogues: Resistance and Re-Sensitisation at the Level of Pharmacokinetics, Pharmacodynamics and Metabolism. Cancers (Basel) 2018; 10:cancers10070240. [PMID: 30041457 PMCID: PMC6071274 DOI: 10.3390/cancers10070240] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 02/07/2023] Open
Abstract
Antimetabolites, in particular nucleobase and nucleoside analogues, are cytotoxic drugs that, starting from the small field of paediatric oncology, in combination with other chemotherapeutics, have revolutionised clinical oncology and transformed cancer into a curable disease. However, even though combination chemotherapy, together with radiation, surgery and immunotherapy, can nowadays cure almost all types of cancer, we still fail to achieve this for a substantial proportion of patients. The understanding of differences in metabolism, pharmacokinetics, pharmacodynamics, and tumour biology between patients that can be cured and patients that cannot, builds the scientific basis for rational therapy improvements. Here, we summarise current knowledge of how tumour-specific and patient-specific factors can dictate resistance to nucleobase/nucleoside analogues, and which strategies of re-sensitisation exist. We revisit well-established hurdles to treatment efficacy, like the blood-brain barrier and reduced deoxycytidine kinase activity, but will also discuss the role of novel resistance factors, such as SAMHD1. A comprehensive appreciation of the complex mechanisms that underpin the failure of chemotherapy will hopefully inform future strategies of personalised medicine.
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Affiliation(s)
- Nikolaos Tsesmetzis
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | - Cynthia B J Paulin
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, 171 65 Stockholm, Sweden.
| | - Sean G Rudd
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, 171 65 Stockholm, Sweden.
| | - Nikolas Herold
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, 171 77 Stockholm, Sweden.
- Paediatric Oncology, Theme of Children's and Women's Health, Karolinska University Hospital Solna, 171 76 Stockholm, Sweden.
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Pastor-Anglada M, Urtasun N, Pérez-Torras S. Intestinal Nucleoside Transporters: Function, Expression, and Regulation. Compr Physiol 2018; 8:1003-1017. [PMID: 29978890 DOI: 10.1002/cphy.c170039] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The gastrointestinal tract is the absorptive organ for nutrients found in foods after digestion. Nucleosides and, to a lesser extent nucleobases, are the late products of nucleoprotein digestion. These metabolites are absorbed by nucleoside (and nucleobase) transporter (NT) proteins. NTs are differentially distributed along the gastrointestinal tract showing also polarized expression in epithelial cells. Concentrative nucleoside transporters (CNTs) are mainly located at the apical side of enterocytes, whereas equilibrative nucleoside transporters (ENTs) facilitate the basolateral efflux of nucleosides and nucleobases to the bloodstream. Moreover, selected nucleotides and the bioactive nucleoside adenosine act directly on intestinal cells modulating purinergic signaling. NT-polarized insertion is tightly regulated. However, not much is known about the modulation of intestinal NT function in humans, probably due to the lack of appropriate cell models retaining CNT functional expression. Thus, the possibility of nutritional regulation of intestinal NTs has been addressed using animal models. Besides the nutrition-related role of NT proteins, orally administered drugs also need to cross the intestinal barrier, this event being a major determinant of drug bioavailability. In this regard, NT proteins might also play a role in pharmacology, thereby allowing the absorption of nucleoside- and nucleobase-derived drugs. The relative broad selectivity of these membrane transporters also suggests clinically relevant drug-drug interactions when using combined therapies. This review focuses on all these physiological and pharmacological aspects of NT protein biology. © 2017 American Physiological Society. Compr Physiol 8:1003-1017, 2018.
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Affiliation(s)
- Marçal Pastor-Anglada
- Biochemistry and Molecular Pharmacology Section, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain.,Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases (CIBER EHD), Instituto de Salud Carlos III, Barcelona, Spain.,Genetics, Molecular Biology and Gene Therapy Program, Institut de Recerca Sant Joan de Déu (IR SJD), Esplugues de Llobregat, Barcelona, Spain
| | - Nerea Urtasun
- Biochemistry and Molecular Pharmacology Section, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain.,Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases (CIBER EHD), Instituto de Salud Carlos III, Barcelona, Spain.,Genetics, Molecular Biology and Gene Therapy Program, Institut de Recerca Sant Joan de Déu (IR SJD), Esplugues de Llobregat, Barcelona, Spain
| | - Sandra Pérez-Torras
- Biochemistry and Molecular Pharmacology Section, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain.,Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases (CIBER EHD), Instituto de Salud Carlos III, Barcelona, Spain.,Genetics, Molecular Biology and Gene Therapy Program, Institut de Recerca Sant Joan de Déu (IR SJD), Esplugues de Llobregat, Barcelona, Spain
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10
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Guillotin V, Galli G, Viallard JF. [Usefulness of thiopurine methyltransferase polymorphism study and metabolites measurement for patients treated by azathioprine]. Rev Med Interne 2018; 39:421-426. [PMID: 29370945 DOI: 10.1016/j.revmed.2017.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 12/18/2017] [Accepted: 12/28/2017] [Indexed: 11/18/2022]
Abstract
Azathioprine is widely used in internal medicine and frequently implicated in occurrence of adverse events. Among these adverse events the bone marrow suppression, a dose-related one, is the most serious because of is potential morbidity and mortality. Severe myelosuppression, associated with abnormal AZA metabolism, is linked to the thiopurine methyltransferase (TPMT) genetic polymorphism that results in a high variability of its activity with 89% of patients with a normal activity, 11% with an intermediate activity, and 0.3% with very low activity leading to a very high risk of bonne marrow suppression. TPMT status can be assessed prior to AZA treatment by measuring enzyme activity or genotyping techniques to identify patients for which the standard dose is not advisable. Furthermore, azathioprine metabolites monitoring is helpful for the follow up of patients, especially in therapeutic failure, to distinguish non-compliant patients from under-dosed, "shunters" or resistant patients.
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Affiliation(s)
- V Guillotin
- Laboratoire d'immunologie de l'hôpital Pellegrin, place Amélié-Raba-Léon, 33000 Bordeaux, France.
| | - G Galli
- Service de médecine interne et immunologie clinique, Hôpital Saint-André, rue Jean-Burguet, 33000 Bordeaux, France
| | - J-F Viallard
- Service de médecine interne, hôpital du Haut-Lévêque, avenue Magellan, 33604 Pessac, France
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11
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LC-MS/MS Analysis of Erythrocyte Thiopurine Nucleotides and Their Association With Genetic Variants in Patients With Neuromyelitis Optica Spectrum Disorders Taking Azathioprine. Ther Drug Monit 2017; 39:5-12. [PMID: 27941536 DOI: 10.1097/ftd.0000000000000362] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Azathioprine is a first-line drug in treating neuromyelitis optica spectrum disorders (NMOSD). To exhibit its bioactivity, azathioprine needs to be converted to thiopurine nucleotides (TPNs) including 6-thioguanine nucleotides (6-TGNs) and 6-methylmercaptopurine nucleotides (6-MMPNs) that are affected by genetic polymorphisms. This study aims to develop an LC-MS/MS method for the analysis of erythrocyte concentrations of TPNs and to evaluate their associations with variants of various genes (MTHFR, TPMT, HLA, SLC29A1, SLC28A2, SLC28A3, ABCB1, and ABCC4) in patients with NMOSD. METHODS Erythrocyte 6-TGNs and 6-MMPNs were converted to their free bases 6-thioguanine and 6-methylmercaptopurine derivative by 1-hour acid hydrolysis at 95°C. An LC-MS/MS method was developed, validated, and used to study 32 patients with NMOSD to determine these free bases. Genetic variants were identified by MassARRAY (Sequenom) and multiple SNaPshot techniques. The associations between genetic variants and the concentrations of TPNs or the 6-MMPNs:6-TGNs ratio were evaluated by PLINK software using linear regression. RESULTS Methanol and water were used for separation with a total run time of 6.5 minutes. The lowest limit of quantification was 0.1 μmol/L with an injection volume of 10 μL. rs10868138 (SLC28A3) was associated with a higher erythrocyte concentration of 6-TGNs (P = 0.031), whereas rs12378361 (SLC28A3) was associated with a lower erythrocyte concentration of 6-TGNs (P = 0.0067). rs507964 (SLC29A1) was significantly associated with a lower erythrocyte concentration of 6-MMPNs (P = 0.024) and a lower 6-MMPNs:6-TGNs ratio (P = 0.029). CONCLUSIONS An LC-MS/MS method for the analysis of erythrocyte TPNs was developed, validated, and used to study 32 patients with NMOSD. SLC29A1 and SLC28A3 were associated with the erythrocyte concentrations of TPNs and 6-MMPNs:6-TGNs ratio. Further studies are needed to confirm these results.
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12
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Li X, Mei S, Gong X, Zhou H, Yang L, Zhou A, Liu Y, Li X, Zhao Z, Zhang X. Relationship between Azathioprine metabolites and therapeutic efficacy in Chinese patients with neuromyelitis optica spectrum disorders. BMC Neurol 2017; 17:130. [PMID: 28679367 PMCID: PMC5498874 DOI: 10.1186/s12883-017-0903-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 06/22/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Neuromyelitis optica spectrum disorders (NMOSD) are demyelinating autoimmune diseases in the central nervous system (CNS) that are characterized by a high relapse rate and the presence of anti-aquaporin 4 antibodies (AQP4-IgG) in the serum. Azathioprine (AZA) is a first-line immunomodulatory drug that is widely used for the treatment of patients with NMOSD. However, the efficacy and safety of AZA vary in different individuals. METHOD Thirty-two patients with NMOSD who regularly took AZA were enrolled in the study at Beijing Tiantan Hospital, Capital Medical University. The efficacy of AZA was evaluated using the expanded disability status scale (EDSS) and the annual relapse rate (ARR). The erythrocyte concentrations of AZA metabolites were detected using an LC-MS/MS method. RESULTS The erythrocyte concentrations of 6-thioguanine nucleotides (6-TGNs) and 6-methylmercaptopurine nucleotides (6-MMPNs) were 202.03 ± 63.35 pmol/8*108 RBC and 1618.90 ± 1607.06 pmol/8*108 RBC, respectively. After the patients had received AZA therapy for more than one year, the EDSS score decreased from 5.21 ± 0.24 to 2.57 ± 0.33 (p < 0.0001), and the ARR decreased from 1.41 ± 0.23 to 0.36 ± 0.09 (p < 0.0001). The 6-TGN and 6-MMPN levels were significantly different between the non-relapsed and relapsed groups (p < 0.0001, p = 0.006, respectively). A higher ARR was significantly correlated with higher erythrocyte concentrations of 6-TGNs (p < 0.0001) and 6-MMPNs (p = 0.004). CONCLUSION AZA can reduce the EDSS score and ARR in NMOSD patients. Additionally, the efficacy of AZA is significantly related to the erythrocyte concentrations of 6-TGNs and 6-MMPNs. Within the safe upper limits, a higher concentration of 6-TGNs is associated with better efficacy of AZA. TRIAL REGISTRATION NUMBER ISRCTN16551495 , retrospectively registered on May 22, 2017.
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Affiliation(s)
- Xindi Li
- Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China.,China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Shenghui Mei
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Xiaoqing Gong
- Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China.,China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Heng Zhou
- Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China.,China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Li Yang
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Anna Zhou
- Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China.,China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Yonghong Liu
- Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China.,China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Xingang Li
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China
| | - Zhigang Zhao
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China.
| | - Xinghu Zhang
- Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China. .,China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, 6 TiantanXili, Dongcheng District, Beijing, 100050, People's Republic of China.
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13
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Combination treatment with 6-mercaptopurine and allopurinol in HepG2 and HEK293 cells - Effects on gene expression levels and thiopurine metabolism. PLoS One 2017; 12:e0173825. [PMID: 28278299 PMCID: PMC5344510 DOI: 10.1371/journal.pone.0173825] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 02/26/2017] [Indexed: 12/13/2022] Open
Abstract
Combination treatment with low-dose thiopurine and allopurinol (AP) has successfully been used in patients with inflammatory bowel disease with a so called skewed thiopurine metabolite profile. In red blood cells in vivo, it reduces the concentration of methylated metabolites and increases the concentration of the phosphorylated ones, which is associated with improved therapeutic efficacy. This study aimed to investigate the largely unknown mechanism of AP on thiopurine metabolism in cells with an active thiopurine metabolic pathway using HepG2 and HEK293 cells. Cells were treated with 6-mercaptopurine (6MP) and AP or its metabolite oxypurinol. The expression of genes known to be associated with thiopurine metabolism, and the concentration of thiopurine metabolites were analyzed. Gene expression levels were only affected by AP in the presence of 6MP. The addition of AP to 6MP affected the expression of in total 19 genes in the two cell lines. In both cell lines the expression of the transporter SLC29A2 was reduced by the combined treatment. Six regulated genes in HepG2 cells and 8 regulated genes in HEK293 cells were connected to networks with 18 and 35 genes, respectively, present at known susceptibility loci for inflammatory bowel disease, when analyzed using a protein-protein interaction database. The genes identified as regulated as well as the disease associated interacting genes represent new candidates for further investigation in the context of combination therapy with thiopurines and AP. However, no differences in absolute metabolite concentrations were observed between 6MP+AP or 6MP+oxypurinol vs. 6MP alone in either of the two cell lines. In conclusion; the effect of AP on gene expression levels requires the presence of 6MP, at least in vitro. Previously described AP-effects on metabolite concentrations observed in red blood cells in vivo could not be reproduced in our cell lines in vitro. AP’s effects in relation to thiopurine metabolism are complex. The network-identified susceptibility genes represented biological processes mainly associated with purine nucleotide biosynthetic processes, lymphocyte proliferation, NF-KB activation, JAK-STAT signaling, and apoptotic signaling at oxidative stress.
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14
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Fernández‐Calotti P, Casulleras O, Antolin M, Guarner F, Pastor‐Anglada M. Galectin‐4 interacts with the drug transporter human concentrative nucleoside transporter 3 to regulate its function. FASEB J 2015; 30:544-54. [DOI: 10.1096/fj.15-272773] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 09/21/2015] [Indexed: 12/31/2022]
Affiliation(s)
- Paula Fernández‐Calotti
- Department of Biochemistry and Molecular BiologyUniversity of BarcelonaInstitute of Biomedicine (IBUB)BarcelonaSpain
- Oncology ProgramNational Biomedical Research Institute of Liver and Gastrointestinal Diseases (CIBER EHD)Instituto de Salud Carlos IIIMadridSpain
| | - Olga Casulleras
- Department of Biochemistry and Molecular BiologyUniversity of BarcelonaInstitute of Biomedicine (IBUB)BarcelonaSpain
- Oncology ProgramNational Biomedical Research Institute of Liver and Gastrointestinal Diseases (CIBER EHD)Instituto de Salud Carlos IIIMadridSpain
| | - María Antolin
- Department of GastroenterologyDigestive System Research UnitInstitut de Recerca Vall d'HebronUniversity Hospital Vall d'HebronUniversitat Autònoma de Barcelona, CIBER EHDBarcelonaSpain
| | - Francisco Guarner
- Department of GastroenterologyDigestive System Research UnitInstitut de Recerca Vall d'HebronUniversity Hospital Vall d'HebronUniversitat Autònoma de Barcelona, CIBER EHDBarcelonaSpain
| | - Marçal Pastor‐Anglada
- Department of Biochemistry and Molecular BiologyUniversity of BarcelonaInstitute of Biomedicine (IBUB)BarcelonaSpain
- Oncology ProgramNational Biomedical Research Institute of Liver and Gastrointestinal Diseases (CIBER EHD)Instituto de Salud Carlos IIIMadridSpain
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15
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Hareedy MS, El Desoky ES, Woillard JB, Thabet RH, Ali AM, Marquet P, Picard N. Genetic variants in 6-mercaptopurine pathway as potential factors of hematological toxicity in acute lymphoblastic leukemia patients. Pharmacogenomics 2015; 16:1119-34. [PMID: 26237184 DOI: 10.2217/pgs.15.62] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIM We investigated the associations between variants in genes coding for enzymes and transporters related to the 6-mercaptopurine pathway and clinical outcomes in pediatric patients with acute lymphoblastic leukemia. MATERIALS & METHODS Statistical association between gender, age and genotypes of selected SNPs, and the risks of hematological toxicity and relapse were investigated using a Cox proportional hazard model in 70 acute lymphoblastic leukemia patients from upper Egypt. RESULTS We found significant associations between ITPA, IMPDH1, SLC29A1, SLC28A2, SLC28A3 and ABCC4 SNPs and one or more of the hematological toxicity manifestations (neutropenia, agranulocytosis and leukopenia); age was significantly related to relapse. CONCLUSION Genetic polymorphisms in enzymes and transporters involved in the 6-mercaptopurine pathway should be considered during its use to avoid hematological toxicity.
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Affiliation(s)
- Mohammad Salem Hareedy
- Department of Pharmacology, Faculty of Medicine, Assiut University, 71515 Assiut, Egypt.,Inserm, UMR-850, Limoges, France
| | - Ehab S El Desoky
- Department of Pharmacology, Faculty of Medicine, Assiut University, 71515 Assiut, Egypt
| | - Jean-Baptiste Woillard
- Inserm, UMR-850, Limoges, France.,Department of Pharmacology, Toxicology & Pharmacovigilance, CHU Limoges, Limoges, France.,Faculty of Medicine, Laboratory of Medical Pharmacology, University of Limoges, Limoges, France
| | - Romany Helmy Thabet
- Department of Pharmacology, Faculty of Medicine, Assiut University, 71515 Assiut, Egypt
| | | | - Pierre Marquet
- Inserm, UMR-850, Limoges, France.,Department of Pharmacology, Toxicology & Pharmacovigilance, CHU Limoges, Limoges, France.,Faculty of Medicine, Laboratory of Medical Pharmacology, University of Limoges, Limoges, France
| | - Nicolas Picard
- Inserm, UMR-850, Limoges, France.,Department of Pharmacology, Toxicology & Pharmacovigilance, CHU Limoges, Limoges, France.,South Egypt Cancer Institute, Assiut University, Assiut, Egypt
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16
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Nicklas JA, Albertini RJ, Vacek PM, Ardell SK, Carter EW, McDiarmid MA, Engelhardt SM, Gucer PW, Squibb KS. Mutagenicity monitoring following battlefield exposures: Molecular analysis of HPRT mutations in Gulf War I veterans exposed to depleted uranium. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2015; 56:594-608. [PMID: 25914382 DOI: 10.1002/em.21956] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 04/06/2015] [Accepted: 04/08/2015] [Indexed: 06/04/2023]
Abstract
Molecular studies that involved cDNA and genomic DNA sequencing as well as multiplex PCR of the HPRT gene were performed to determine the molecular mutational spectrum for 1,377 HPRT mutant isolates obtained from 61 Veterans of the 1991 Gulf War, most of whom were exposed to depleted uranium (DU). Mutant colonies were isolated from one to four times from each Veteran (in 2003, 2005, 2007, and/or 2009). The relative frequencies of the various types of mutations (point mutations, deletions, insertions, etc.) were compared between high versus low DU exposed groups, (based on their urine U concentration levels), with HPRT mutant frequency (as determined in the companion paper) and with a database of historic controls. The mutational spectrum includes all classes of gene mutations with no significant differences observed in Veterans related to their DU exposures.
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Affiliation(s)
- Janice A Nicklas
- Department of Pediatrics, University of Vermont College of Medicine, Burlington, Vermont
| | - Richard J Albertini
- Department of Pathology, University of Vermont College of Medicine, Burlington, Vermont
- Biostatistics Unit, University of Vermont College of Medicine, Burlington, Vermont
| | - Pamela M Vacek
- Center for Clinical and Translational Science - Biomedical Informatics Unit, University of Vermont, Burlington, Vermont
| | - Stephanie K Ardell
- Division of Newborn Medicine, Department of Pediatrics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Elizabeth W Carter
- Center for Clinical and Translational Science - Biomedical Informatics Unit, University of Vermont, Burlington, Vermont
| | - Melissa A McDiarmid
- Occupational Health Program, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | | | - Patricia W Gucer
- Occupational Health Program, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Katherine S Squibb
- Occupational Health Program, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
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17
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Song JH, Cho KM, Kim HJ, Kim YK, Kim NY, Kim HJ, Lee TH, Hwang SY, Kim TS. Concentrative nucleoside transporter 3 as a prognostic indicator for favorable outcome of t(8;21)-positive acute myeloid leukemia patients after cytarabine-based chemotherapy. Oncol Rep 2015; 34:488-94. [PMID: 25955569 DOI: 10.3892/or.2015.3959] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/18/2015] [Indexed: 11/06/2022] Open
Abstract
Although acute myeloid leukemia (AML) exhibits diverse responses to chemotherapy, patients harboring the t(8;21) translocation are part of a favorable risk group. However, the reason why this subgroup is more responsive to cytarabine-based therapy has not been elucidated. In the present study, we analyzed expression levels of cytarabine metabolism-related genes in patients diagnosed with AML with or without t(8;21) and investigated their correlation with clinical outcomes after cytarabine-based therapy. Among the 8 genes studied, expression of the concentrative nucleoside transporter 3 (CNT3) gene was significantly higher in t(8;21)-positive patients compared to the others in the test population and the validation cohort (P<0.001 in Mann-Whitney U test; P<0.002 in Pearson's correlation analysis). Additionally, in both multivariate and univariate analyses, t(8;21)-positive patients categorized in a higher CNT3 expression tertile had longer disease-free survival [hazard ratio (HR), 0.117; 95% confidence interval (CI), 0.025-0.557; P=0.008] and overall survival (HR, 0.062; 95% CI, 0.007-0.521; P=0.010) compared to t(8;21)-positive patients in a lower CNT3 expression tertile. Notably, these trends did not occur in t(8;21)-negative patients. Our results demonstrate that CNT3 expression is associated with overall favorable outcomes and is predictive of clinical outcomes in AML patients with t(8;21). This suggests that CNT3 expression can be used to optimize treatment strategies for AML patients.
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Affiliation(s)
- Ju Han Song
- Division of Life Sciences, School of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Kyung-Min Cho
- Division of Life Sciences, School of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Hyeoung-Joon Kim
- Genome Research Center for Hematopoietic Diseases, Chonnam National University Hwasun Hospital, Hwasun, Republic of Korea
| | - Yeo-Kyeoung Kim
- Genome Research Center for Hematopoietic Diseases, Chonnam National University Hwasun Hospital, Hwasun, Republic of Korea
| | - Nan Young Kim
- Genome Research Center for Hematopoietic Diseases, Chonnam National University Hwasun Hospital, Hwasun, Republic of Korea
| | - Hee-Je Kim
- Catholic Blood and Marrow Transplantation Center, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - Tae-Hyang Lee
- Catholic Blood and Marrow Transplantation Center, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - Seung Yong Hwang
- Division of Molecular and Life Science and GenoCheck Co., Ltd., Hanyang University, Ansan, Republic of Korea
| | - Tae Sung Kim
- Division of Life Sciences, School of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
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18
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Pastor-Anglada M, Pérez-Torras S. Nucleoside transporter proteins as biomarkers of drug responsiveness and drug targets. Front Pharmacol 2015; 6:13. [PMID: 25713533 PMCID: PMC4322540 DOI: 10.3389/fphar.2015.00013] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 01/13/2015] [Indexed: 12/13/2022] Open
Abstract
Nucleoside and nucleobase analogs are currently used in the treatment of solid tumors, lymphoproliferative diseases, viral infections such as hepatitis and AIDS, and some inflammatory diseases such as Crohn. Two gene families are implicated in the uptake of nucleosides and nucleoside analogs into cells, SCL28 and SLC29. The former encodes hCNT1, hCNT2, and hCNT3 proteins. They translocate nucleosides in a Na+ coupled manner with high affinity and some substrate selectivity, being hCNT1 and hCNT2 pyrimidine- and purine-preferring, respectively, and hCNT3 a broad selectivity transporter. SLC29 genes encode four members, being hENT1 and hENT2 the only two which are unequivocally implicated in the translocation of nucleosides and nucleobases (the latter mostly via hENT2) at the cell plasma membrane. Some nucleoside-derived drugs can also interact with and be translocated by members of the SLC22 gene family, particularly hOCT and hOAT proteins. Inter-individual differences in transporter function and perhaps, more importantly, altered expression associated with the disease itself might modulate the transporter profile of target cells, thereby determining drug bioavailability and action. Drug transporter pharmacology has been periodically reviewed. Thus, with this contribution we aim at providing a state-of-the-art overview of the clinical evidence generated so far supporting the concept that these membrane proteins can indeed be biomarkers suitable for diagnosis and/or prognosis. Last but not least, some of these transporter proteins can also be envisaged as drug targets, as long as they can show “transceptor” functions, in some cases related to their role as modulators of extracellular adenosine levels, thereby providing a functional link between P1 receptors and transporters.
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Affiliation(s)
- Marçal Pastor-Anglada
- Molecular Pharmacology and Experimental Therapeutics, Department of Biochemistry and Molecular Biology, Institute of Biomedicine, University of Barcelona, Barcelona Spain ; Oncology Program, CIBER ehd, National Biomedical Research Institute on Liver and Gastrointestinal Diseases, Instituto de Salud Carlos III, Barcelona Spain
| | - Sandra Pérez-Torras
- Molecular Pharmacology and Experimental Therapeutics, Department of Biochemistry and Molecular Biology, Institute of Biomedicine, University of Barcelona, Barcelona Spain ; Oncology Program, CIBER ehd, National Biomedical Research Institute on Liver and Gastrointestinal Diseases, Instituto de Salud Carlos III, Barcelona Spain
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19
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Steroid hormones are novel nucleoside transport inhibitors by competition with nucleosides for their transporters. Biochem Biophys Res Commun 2014; 443:505-10. [DOI: 10.1016/j.bbrc.2013.11.132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Accepted: 11/29/2013] [Indexed: 11/17/2022]
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20
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Karim H, Appell ML, Fotoohi A. Comparison of three methods for measuring thiopurine methyltransferase activity in red blood cells and human leukemia cells. J Chromatogr B Analyt Technol Biomed Life Sci 2013; 939:80-5. [PMID: 24113235 DOI: 10.1016/j.jchromb.2013.08.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 08/23/2013] [Accepted: 08/29/2013] [Indexed: 10/26/2022]
Abstract
Thiopurine efficacy is partly reflected by the genetic polymorphism of the thiopurine methyltransferase (TPMT) enzyme, which is responsible for variation in the metabolism, toxicity and therapeutic efficacy of the thiopurines azathioprine (AZA), 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG). Determination of TPMT activity before administration of thiopurines is thus crucial for individualized dosing in order to prevent toxicity in TPMT deficient individuals. These individuals must be treated with markedly lower (eg, 5-10% of the standard) doses of the prescribed medications. This paper describes a comparison of three different methods for the quantification of TPMT activity in red blood cells (RBC) and cultured human cell lines. We succeeded to perform the measurement of TPMT activity in a minimum amount of 1×10(6) cultured cells with an HPLC-UV system modified and optimized in our laboratory. The TPMT activity was linearly correlated with the cell concentration of the cultured cell line in a range of 1-10×10(6) cells. A significant correlation of determination of TPMT activity in RBC between radiometric detection by HPLC, classic radiochemical detection and UV detection by HPLC, was observed, correlation coefficient (r) were 0.72 and 0.73, respectively. The within-day and day-to-day coefficients of variation of the HPLC-UV-based method were 8% and 16%, respectively. The evaluation of the methods was demonstrated by studying the TPMT activity in RBC isolated from 198 patients, as well as in MOLT4 leukemic cell line and its sub-cell lines with acquired resistance to 6-MP and 6-TG.
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Affiliation(s)
- Hazhar Karim
- Department of Medicine, Clinical Pharmacology Unit, Karolinska Institutet, Karolinska University Hospital, SE-171 76 Stockholm, Sweden.
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21
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Karim H, Ghalali A, Lafolie P, Vitols S, Fotoohi AK. Differential role of thiopurine methyltransferase in the cytotoxic effects of 6-mercaptopurine and 6-thioguanine on human leukemia cells. Biochem Biophys Res Commun 2013; 437:280-6. [PMID: 23811272 DOI: 10.1016/j.bbrc.2013.06.067] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 06/18/2013] [Indexed: 11/24/2022]
Abstract
The thiopurine antimetabolites, 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG) are inactive pro-drugs that require intracellular metabolism for activation to cytotoxic metabolites. Thiopurine methyltransferase (TPMT) is one of the most important enzymes in this process metabolizing both 6-MP and 6-TG to different methylated metabolites including methylthioinosine monophosphate (meTIMP) and methylthioguanosine monophosphate (meTGMP), respectively, with different suggested pharmacological and cytotoxic properties. While meTIMP is a potent inhibitor of de novo purine synthesis (DNPS) and significantly contributes to the cytotoxic effects of 6-MP, meTGMP, does not add much to the effects of 6-TG, and the cytotoxicity of 6-TG seems to be more dependent on incorporation of thioguanine nucleotides (TGNs) into DNA rather than inhibition of DNPS. In order to investigate the role of TPMT in metabolism and thus, cytotoxic effects of 6-MP and 6-TG, we knocked down the expression of the gene encoding the TPMT enzyme using specifically designed small interference RNA (siRNA) in human MOLT4 leukemia cells. The knock-down was confirmed at RNA, protein, and enzyme function levels. Apoptosis was determined using annexin V and propidium iodide staining and FACS analysis. The results showed a 34% increase in sensitivity of MOLT4 cells to 1μM 6-TG after treatment with TPMT-targeting siRNA, as compared to cells transfected with non-targeting siRNA, while the sensitivity of the cells toward 6-MP was not affected significantly by down-regulation of the TPMT gene. This differential contribution of the enzyme TPMT to the cytotoxicity of the two thiopurines is probably due to its role in formation of the meTIMP, the cytotoxic methylated metabolite of 6-MP, while in case of 6-TG methylation by TPMT substantially deactivates the drug.
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Affiliation(s)
- Hazhar Karim
- Department of Medicine, Clinical Pharmacology Unit, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
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22
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Blaker PA, Arenas-Hernandez M, Marinaki AM, Sanderson JD. The pharmacogenetic basis of individual variation in thiopurine metabolism. Per Med 2012; 9:707-725. [DOI: 10.2217/pme.12.85] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Thiopurines are an important class of immunosuppressive therapy, which have been used in clinical practice for over 50 years. Despite this extensive experience many of the pharmacodynamic and pharmacokinetic properties of these drugs remain unknown. As a consequence there is often no clear explanation for the individual variation in response to treatment, both in terms of efficacy or adverse drug reactions. This review, which emphasizes practice in gastroenterology, summarizes the current understanding of thiopurine drug metabolism and highlights the role of nongenetic and genetic factors other than TPMT, which should be a focus for future research. Correlation of polymorphic variations in these genes with clinical outcomes is expected to clarify the basis for interindividual differences in thiopurine metabolism and enable a more personalized approach to therapy.
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Affiliation(s)
- Paul Andrew Blaker
- Department of Gastroenterology, 1st Floor College House, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, London, UK
| | - Monica Arenas-Hernandez
- The Purine Research Laboratory, Guy’s & St Thomas’ Hospitals NHS Foundation Trust , London, UK
| | - Anthony Marin Marinaki
- The Purine Research Laboratory, Guy’s & St Thomas’ Hospitals NHS Foundation Trust , London, UK
| | - Jeremy David Sanderson
- Department of Gastroenterology, 1st Floor College House, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, London, UK
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23
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Sprowl JA, Mikkelsen TS, Giovinazzo H, Sparreboom A. Contribution of tumoral and host solute carriers to clinical drug response. Drug Resist Updat 2012; 15:5-20. [PMID: 22459901 DOI: 10.1016/j.drup.2012.01.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Members of the solute carrier family of transporters are responsible for the cellular uptake of a broad range of endogenous compounds and xenobiotics in multiple tissues. Several of these solute carriers are known to be expressed in cancer cells or cancer cell lines, and decreased cellular uptake of drugs potentially contributes to the development of resistance. As result, the expression levels of these proteins in humans have important consequences for an individual's susceptibility to certain drug-induced side effects, interactions, and treatment efficacy. In this review article, we provide an update of this rapidly emerging field, with specific emphasis on the direct contribution of solute carriers to anticancer drug uptake in tumors, the role of these carriers in regulation of anticancer drug disposition, and recent advances in attempts to evaluate these proteins as therapeutic targets.
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Affiliation(s)
- Jason A Sprowl
- Department of Pharmaceutical Sciences, St Jude Children's Research Hospital, Memphis, TN 38105, USA
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24
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Fernández-Calotti PX, Colomer D, Pastor-Anglada M. Translocation of nucleoside analogs across the plasma membrane in hematologic malignancies. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2012; 30:1324-40. [PMID: 22132993 DOI: 10.1080/15257770.2011.597372] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Nucleoside analogs are currently used in the treatment of various hematologic malignancies due to their ability to induce apoptosis of lymphoid cells. For nucleoside-derived drugs to exert their action, they must enter cells via nucleoside transporters from two gene families, SLC28 and SLC29 (CNT and ENT, respectively). Once inside the cell, these drugs must be phosphorylated to their active forms. In contrast, some members of the ATP-binding cassette (ABC) protein family have been identified as responsible for the efflux of the phosphorylated forms of these nucleoside-derived drugs. Here, we review the main nucleoside analogs used in hematologic malignancies and focus especially on those that are currently used in chronic lymphocytic leukemia (CLL). Moreover, we discuss the pharmacological profile of the nucleoside transporters, which determines the bioavailability of and cell sensitivity to these nucleoside-derived drugs. We also discuss the expression of nucleoside transporters and their activities in CLL as well as the possibility of modulating these transporter activities as a means of modulating intracellular drug availability and, consequently, responsiveness to therapy.
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Affiliation(s)
- Paula X Fernández-Calotti
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona & CIBER EHD, Barcelona, Spain.
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25
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CONKLIN LS, CUFFARI C, OKAZAKI T, MIAO Y, SAATIAN B, CHEN TE, TSE M, BRANT SR, LI X. 6-Mercaptopurine transport in human lymphocytes: correlation with drug-induced cytotoxicity. J Dig Dis 2012; 13:82-93. [PMID: 22257476 PMCID: PMC3758926 DOI: 10.1111/j.1751-2980.2011.00556.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE 6-mercaptopurine (6-MP) is efficacious in the treatment of inflammatory bowel disease (IBD). However, about one-third of patients respond poorly to therapy. This study aimed to characterize the inherent differences in 6-MP transport that may cotribute to the differences in treatment responses. METHODS Intracellular 6-MP accumulation was assayed in Epstein-Barr virus (EBV)-transformed lymphocytes from IBD patients, using (14) C-radiolabeled 6-MP. Cell proliferation was determined by methyl thiazolyl tetrazolium (MTT) assay. Apoptosis was assayed based on the activation of caspase 3. The expressions of 15 potential 6-MP transporters were evaluated by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS Intracellular 6-MP accumulation, varying significantly among patients, was carrier-dependent and partially sodium-dependent. 6-MP cytotoxicity was, at least in part, due to apoptosis and correlated with intracellular drug accumulation. The efflux transporters did not appear to contribute to the variability of intracellular drug accumulation between patients, since none correlated with drug accumulation or cytotoxicity. Rather, differential expression of five influx/uptake transporters might be a key contributor to the difference in the accumulation of and susceptibility to the drug. CONCLUSIONS The heterogeneity of the drug transporters may be the reason for the therapeutic sensitivity of 6-MP in IBD patients. As the 6-MP uptake is a carrier-mediated and partially sodium-dependent process, future studies are necessary to evaluate the role of the putative transporters and their correlation with drug sensitivity in patients.
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Affiliation(s)
- Laurie S. CONKLIN
- Division of Pediatric Gastroenterology and Nutrition, Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Carmen CUFFARI
- Division of Pediatric Gastroenterology and Nutrition, Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Toshihiko OKAZAKI
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yinglei MIAO
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Bahman SAATIAN
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Tian-E. CHEN
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ming TSE
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Steven R. BRANT
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Xuhang LI
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Chouchana L, Narjoz C, Beaune P, Loriot MA, Roblin X. Review article: the benefits of pharmacogenetics for improving thiopurine therapy in inflammatory bowel disease. Aliment Pharmacol Ther 2012; 35:15-36. [PMID: 22050052 DOI: 10.1111/j.1365-2036.2011.04905.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Thiopurines represent an effective and widely prescribed therapy in inflammatory bowel disease (IBD). Concerns about toxicity, mainly resulting from a wide inter-individual variability in thiopurine metabolism, restrict their use. Optimal thiopurine dosing is challenging for preventing adverse drug reactions and improving clinical response. AIM To review efficacy and toxicity of thiopurines in IBD. To provide pharmacogenetic-based therapeutic recommendations. METHODS We conducted a query on PubMed database using 'inflammatory bowel disease', 'thiopurine', 'azathioprine', '6-mercaptopurine', 'TPMT', 'pharmacogenetics', 'TDM', and selected relevant articles, especially clinical studies. RESULTS Thiopurine metabolism - key enzyme: thiopurine S-methyltransferase (TPMT) - modulates clinical response, as it results in production of the pharmacologically active and toxic metabolites, the thioguanine nucleotides (6-TGN). Adjusting dosage according to TPMT status and/or metabolite blood levels is recommended for optimising thiopurine therapy (e.g. improving response rate up to 30% or decreasing haematological adverse events of 25%). Other enzymes or transporters of interest, as inosine triphosphatase (ITPase), glutathione S-transferase (GST), xanthine oxidase (XO), aldehyde oxidase (AOX), methylene tetrahydrofolate reductase (MTHFR) and ATP-binding cassette sub-family C member 4 (ABCC4) are reviewed and discussed for clinical relevance. CONCLUSIONS Based on the literature data, we provide a therapeutic algorithm for thiopurines therapy with starting dose recommendations depending on TPMT status and thereafter dose adjustments according to five metabolite profiles identified with therapeutic drug monitoring (TDM). This algorithm allows a dosage individualisation to optimise the management of patients under thiopurine. Furthermore, identification of new pharmacogenetic biomarkers is promising for ensuring maximal therapeutic response to thiopurines with a minimisation of the risk for adverse events.
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Affiliation(s)
- L Chouchana
- Assistance publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Biochimie, Pharmacogénétique et Oncologie Moléculaire, Paris, France
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27
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Nishimura T, Tanaka J, Tomi M, Seki Y, Kose N, Sai Y, Nakashima E. Enhancement of Zidovudine Transfer to Molt-4 Cells, a Human T-Cell Model, by Dehydroepiandrosterone Sulfate. J Pharm Sci 2011; 100:3959-67. [DOI: 10.1002/jps.22624] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 04/07/2011] [Accepted: 04/26/2011] [Indexed: 11/10/2022]
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Karim H, Hashemi J, Larsson C, Moshfegh A, Fotoohi AK, Albertioni F. The pattern of gene expression and gene dose profiles of 6-Mercaptopurine- and 6-Thioguanine-resistant human leukemia cells. Biochem Biophys Res Commun 2011; 411:156-61. [PMID: 21723252 DOI: 10.1016/j.bbrc.2011.06.120] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 06/17/2011] [Indexed: 11/25/2022]
Abstract
Exposure of MOLT4 human T-cell leukemia cells to 6-Mercaptopurine (6-MP) and 6-Thioguanine (6-TG) resulted in acquired resistance associated with attenuated expression of the genes encoding concentrative nucleoside transporter 3 (CNT3) and equilibrative nucleoside transporter 2 (ENT2). To identify other alterations at the RNA and DNA levels associated with 6-MP- and 6-TG resistance, we compared here the patterns of gene expression and DNA copy number profiles of resistant sublines to those of the parental wild-type cells. The mRNA levels for two nucleoside transporters were down-regulated in both of the thiopurine-resistant sublines. Moreover, both of these cell lines expressed genes encoding the enzymes of purine nucleotide composition and synthesis, including adenylate kinase 3-like 1 and guanosine monophosphate synthetase at significantly lower levels than wild-type cells. In addition, expression of the mRNA for a specialized DNA polymerase, human terminal transferase encoded by the terminal deoxynucleotidyl transferase (DNTT) gene, was 122- and 93-fold higher in 6-TG- and 6-MP-resistant cells, respectively. The varying responses to 6-MP- and 6-TG observed here may help identify novel cellular targets and modalities of resistance to thiopurines, as well as indicating new potential approaches to individualization therapy with these drugs.
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Affiliation(s)
- Hazhar Karim
- Department of Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Karolinska University Hospital, SE-171 76 Stockholm, Sweden
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29
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Host-based ribavirin resistance influences hepatitis C virus replication and treatment response. J Virol 2011; 85:7273-83. [PMID: 21543469 DOI: 10.1128/jvi.00629-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Many individuals infected with hepatitis C virus (HCV) develop a chronic infection, and of those who are treated with pegylated interferon and ribavirin (RBV), many do not respond. While the nucleoside analog RBV improves treatment outcome, and will likely be an important component of therapy with next-generation viral inhibitors, RBV's mechanism is controversial. Most of RBV's proposed mechanisms require RBV import into cells. Therefore, we explored whether host-based RBV resistance develops through reduced cellular uptake, akin to chemotherapy resistance in some cancers. We examined the effect of host-based RBV resistance on HCV replication in cultured hepatoma Huh7.5 liver cells and whether RBV resistance develops in HCV patients. When Huh7.5 cells were exposed to RBV, resistance developed through reduced RBV uptake via the ENT1 nucleoside transporter and antiviral efficacy was reduced. The uptake defect in RBV-resistant cells was specific to RBV, since transport of another ENT1 substrate, cytidine, was unaffected. Importantly, RBV uptake significantly declined in HCV patient peripheral blood mononuclear cells (PBMCs) following 4 weeks of therapy. Furthermore, maintenance of RBV uptake correlated with rapid treatment response. Our results uncovered a novel form of antiviral drug resistance and suggest that host-based RBV resistance develops in HCV patients undergoing therapy and that maintenance of RBV uptake may contribute to rapid viral clearance.
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30
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Peng XX, Shi Z, Tiwari AK, Damaraju VL, Fu L, Cass CE, Ashby CR, Kruh GD, Chen ZS. Up-regulation of P-glycoprotein confers acquired resistance to 6-mercaptopurine in human chronic myeloid leukemia cells. Oncol Lett 2011; 2:549-556. [PMID: 22866119 DOI: 10.3892/ol.2011.288] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 03/11/2011] [Indexed: 11/05/2022] Open
Abstract
To investigate the mechanisms of cellular resistance to 6-mercaptopurine (6-MP) in chronic myeloid leukemia (CML), a 6-MP resistant cell line (K562-MP5) was established by stepwise selection of the CML cell line (K562). The results of the drug sensitivity analysis of the K562-MP5 cell line revealed the cells to be 339-fold more resistant to 6-MP compared with the parental K562 cells. K562-MP5 cells exhibited decreased accumulation and increased efflux of [(14)C]6-MP and its metabolites. In addition, K562-MP5 cells showed increased [(3)H]MTX transport. K562-MP5 cells over-expressed P-glycoprotein (P-gp) and up-regulated MDR1 mRNA levels. Taken together, these results suggest that the up-regulation of P-gp, which contributes to the decreased accumulation by increasing the efflux of 6-MP and its metabolites, underlies the mechanism of 6-MP resistance in K562 cells.
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Affiliation(s)
- Xing-Xiang Peng
- Department of Pharmaceutical Sciences, College of Pharmacy and Allied Health Professions, St. John's University, Queens, NY 11439, USA
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Cano-Soldado P, Pastor-Anglada M. Transporters that translocate nucleosides and structural similar drugs: structural requirements for substrate recognition. Med Res Rev 2011; 32:428-57. [DOI: 10.1002/med.20221] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Pedro Cano-Soldado
- Departament de Bioquímica i Biologia Molecular; Institut de Biomedicina de la Universitat de Barcelona (IBUB); Universitat de Barcelona and CIBER EHD; Barcelona Spain
| | - Marçal Pastor-Anglada
- Departament de Bioquímica i Biologia Molecular; Institut de Biomedicina de la Universitat de Barcelona (IBUB); Universitat de Barcelona and CIBER EHD; Barcelona Spain
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32
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Li F, Fridley BL, Matimba A, Kalari KR, Pelleymounter L, Moon I, Ji Y, Jenkins GD, Batzler A, Wang L, Weinshilboum RM. Ecto-5'-nucleotidase and thiopurine cellular circulation: association with cytotoxicity. Drug Metab Dispos 2010; 38:2329-38. [PMID: 20855458 DOI: 10.1124/dmd.110.035220] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Thiopurine drugs such as 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG) are used to treat acute lymphoblastic leukemia of childhood. To test the hypothesis that variation in the expression of genes within the "thiopurine pathway" might influence 6-MP and 6-TG sensitivity, we generated basal gene expression profiles and IC(50) values for both of these thiopurine drugs using a model system consisting of 194 Human Variation Panel lymphoblastoid cell lines. Association analysis showed that thiopurine S-methyltransferase, ecto-5'-nucleotidase (NT5E), and multidrug resistance protein 4 (ABCC4) expression were correlated with thiopurine cytotoxicity. Those observations suggested the possible existence of a "thiopurine cellular circulation" involving nucleotide efflux by ABCC4, hydrolysis of thiopurine nucleotide monophosphates outside of the cell by NT5E, and subsequent transport of thiopurine nucleosides back into the cell by nucleoside transporters. The existence of this cellular circulation was confirmed by a series of functional experiments performed with cultured cells stably or transiently transfected with ABCC4 and/or NT5E. Because of the central role of NT5E in this cellular circulation, the NT5E gene was resequenced using 287 DNA samples from three ethnic groups, with the identification of 68 single nucleotide polymorphisms (SNPs), 46 of which were novel. Several SNPs in the 5'-flanking region of NT5E were highly correlated with expression, rs9450278 having the lowest p value (p = 2.4 × 10(-10), R = -0.376). The thiopurine cellular circulation and genetic polymorphisms for genes encoding the proteins involved should be incorporated into future studies of thiopurine drug therapy and effect.
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Affiliation(s)
- Fang Li
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA
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33
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Errasti-Murugarren E, Pastor-Anglada M. Drug transporter pharmacogenetics in nucleoside-based therapies. Pharmacogenomics 2010; 11:809-41. [PMID: 20504255 DOI: 10.2217/pgs.10.70] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
This article focuses on the different types of transporter proteins that have been implicated in the influx and efflux of nucleoside-derived drugs currently used in the treatment of cancer, viral infections (i.e., AIDS) and other conditions, including autoimmune and inflammatory diseases. Genetic variations in nucleoside-derived drug transporter proteins encoded by the gene families SLC15, SLC22, SLC28, SLC29, ABCB, ABCC and ABCG will be specifically considered. Variants known to affect biological function are summarized, with a particular emphasis on those for which clinical correlations have already been established. Given that relatively little is known regarding the genetic variability of the players involved in determining nucleoside-derived drug bioavailability, it is anticipated that major challenges will be faced in this area of research.
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Affiliation(s)
- Ekaitz Errasti-Murugarren
- The Department of Biochemistry and Molecular Biology, Institute of Biomedicine, University of Barcelona, Diagonal 645, 08028 Barcelona, Spain
- Center for Biomedical Research Network in the Subject Area of Liver and Digestive Diseases (CIBERehd), Barcelona 08071, Spain
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34
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Rius M, Keller D, Brom M, Hummel-Eisenbeiss J, Lyko F, Keppler D. Vectorial Transport of Nucleoside Analogs from the Apical to the Basolateral Membrane in Double-Transfected Cells Expressing the Human Concentrative Nucleoside Transporter hCNT3 and the Export Pump ABCC4. Drug Metab Dispos 2010; 38:1054-63. [DOI: 10.1124/dmd.110.032664] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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35
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Reduced ribavirin antiviral efficacy via nucleoside transporter-mediated drug resistance. J Virol 2009; 83:4538-47. [PMID: 19244331 DOI: 10.1128/jvi.02280-08] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Treatment for hepatitis C virus infection currently consists of pegylated interferon and ribavirin (RBV), a nucleoside analog. Although RBV clearly plays a role in aiding the treatment response, its antiviral mechanism is unclear. Regardless of the specific mechanism of RBV, we hypothesize that differences in levels of cellular uptake of RBV may affect antiviral efficacy and treatment success and that cells may become RBV resistant through reduced uptake. We monitored RBV uptake in various cell lines and determined the effect of uptake capacity on viral replication. RBV-resistant cells demonstrated reduced RBV uptake and increased growth of a model RNA virus, poliovirus, in the presence of RBV. Overexpression of equilibrative nucleoside transporter 1 (ENT1) or concentrative nucleoside transporter 3 (CNT3) increased RBV uptake in RBV-sensitive cell lines and restored the uptake defect in most RBV-resistant cell lines. However, CNT3 is not expressed in Huh-7 liver cells, and inhibition of concentrative transport did not affect RBV uptake. Blocking equilibrative transport using the inhibitor nitrobenzylmercaptopurine riboside recapitulated the RBV-resistant phenotype in RBV-sensitive cell lines, with a reduction in RBV uptake and increased poliovirus growth. Taken together, these results indicate that RBV uptake is restricted primarily to ENT1 in the cell lines examined. Interestingly, some RBV-resistant cell lines may compensate for reduced ENT1-mediated nucleoside uptake by increasing the activity of an alternative nucleoside transporter, ENT2. It is possible that RBV uptake affects the antiviral treatment response, either through natural differences in patients or through acquired resistance.
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36
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Ardiani A, Goyke A, Black ME. Mutations at serine 37 in mouse guanylate kinase confer resistance to 6-thioguanine. Protein Eng Des Sel 2009; 22:225-32. [PMID: 19136674 DOI: 10.1093/protein/gzn078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Guanylate kinase (GMK) is an essential nucleoside monophosphate kinase that catalyzes the phosphorylation of guanine-monophosphate (GMP) and dGMP to yield GDP and dGDP, respectively, important precursors for nucleotide synthesis. GMK is also responsible for the activation of 6-thioguanine (6-TG), a drug widely used as chemotherapeutic agent to treat leukemia. Several mechanisms of resistance to 6-TG have been reported but a subset of drug resistant cells cannot be explained by these mechanisms. We propose that mutations in GMK could result in drug resistance. Because cells require the presence of a functional GMK for viability, mutations that arise that lead to 6-TG resistance must retain activity toward GMP. We report three amino acid substitutions at serine 37 (S37) in mouse GMK that display activity toward GMP by conferring genetic complementation to a conditional GMK-deficient Escherichia coli and in enzyme assays. When 6-TG is included in complementation studies, cells expressing wild-type GMK are sensitive whereas all S37 mutants examined are able to effectively discriminate against 6-TG and display a drug resistance phenotype. Activity of the three S37 mutant enzymes toward clinically relevant concentrations of 6-TGMP is undetectable. Mutations in GMK, therefore, represent a previously undescribed mechanism for 6-TG resistance.
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Affiliation(s)
- Andressa Ardiani
- School of Molecular Biosciences, Washington State University, PO Box 646534, Pullman,WA 99164-6534, USA
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37
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Pastor-Anglada M, Cano-Soldado P, Errasti-Murugarren E, Casado FJ. SLC28 genes and concentrative nucleoside transporter (CNT) proteins. Xenobiotica 2008; 38:972-94. [PMID: 18668436 DOI: 10.1080/00498250802069096] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The human concentrative nucleoside transporter (hCNT) protein family has three members, hCNT1, 2, and 3, encoded by SLC28A1, A2, and A3 genes, respectively. hCNT1 and hCNT2 translocate pyrimidine- and purine-nucleosides, respectively, by a sodium-dependent mechanism, whereas hCNT3 shows broad substrate selectivity and the unique ability of translocating nucleosides both in a sodium- and a proton-coupled manner. hCNT proteins are also responsible for the uptake of most nucleoside-derived antiviral and anticancer drugs. Thus, hCNTs are key pharmacological targets. This review focuses on several crucial aspects of hCNT biology and pharmacology: protein structure-function, structural determinants for transportability, pharmacogenetics of hCNT-encoding genes, role of hCNT proteins in nucleoside-based therapeutics, and finally hCNT physiology.
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Affiliation(s)
- M Pastor-Anglada
- Facultat de Biologia, Departament de Bioquimica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain.
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38
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Hoover S, Striker R. Thiopurines inhibit bovine viral diarrhea virus production in a thiopurine methyltransferase-dependent manner. J Gen Virol 2008; 89:1000-1009. [PMID: 18343842 DOI: 10.1099/vir.0.83381-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The family Flaviviridae comprises positive-strand RNA viral pathogens of humans and livestock with few treatment options. We have previously shown that azathioprine (AZA) has in vitro activity against bovine viral diarrhea virus (BVDV). While the mechanism of inhibition is unknown, AZA and related thiopurine nucleoside analogues have been used as immunosuppressants for decades and both AZA metabolites and cellular genes involved in AZA metabolism have been extensively characterized. Here, we show that only certain riboside metabolites have antiviral activity and identify the most potent known antiviral AZA metabolite as 6-methylmercaptopurine riboside (6MMPr). The antiviral activity of 6MMPr is antagonized by adenosine, and is specific to BVDV and not to the related yellow fever virus. An essential step in the conversion of AZA to 6MMPr is the addition of a methyl group onto the sulfur atom attached to position six of the purine ring. Intracellularly, the methyl group is added by thiopurine methyltransferase (TPMT), an S-adenosyl methionine-dependent methyltransferase. Either chemically bypassing or inhibiting TPMT modulates antiviral activity of AZA metabolites. TPMT exists in several variants with varying levels of activity and since 6MMPr is a potent antiviral, the antiviral activity of AZA may be modulated by host genetics.
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Affiliation(s)
- Spencer Hoover
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, 1550 Linden Drive, Madison, WI, USA
| | - Rob Striker
- Department of Medicine, University of Wisconsin, Madison, W. S. Middleton Memorial Veteran's Hospital, Madison, WI, USA.,Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, 1550 Linden Drive, Madison, WI, USA
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Leung GPH, Tse CM. The role of mitochondrial and plasma membrane nucleoside transporters in drug toxicity. Expert Opin Drug Metab Toxicol 2008; 3:705-18. [PMID: 17916056 DOI: 10.1517/17425255.3.5.705] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Many anticancer and antiviral drugs are nucleoside analogues, which interfere with nucleotide metabolism and DNA replication to produce pharmacological effects. Clinical efficacy and toxicity of nucleoside drugs are closely associated with nucleoside transporters because they mediate the transport of nucleoside drugs across biological membranes. Two families of human nucleoside transporters (equilibrative nucleoside transporters and concentrative nucleoside transporters) have been extensively studied for several decades. They are widely distributed, from the plasma membrane to membranes of organelles such as mitochondria, and the distribution differs in different tissues. In addition, they have different specificities to nucleoside drugs. The characteristics of equilibrative and concentrative nucleoside transporters affect the therapeutic outcomes achieved with anticancer and antiviral nucleoside drugs. In this review, an overview of the role of mitochondrial and plasma membrane nucleoside transporters in nucleoside drug toxicity is provided. Rational design and therapeutic application of nucleoside analogues are also discussed.
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Affiliation(s)
- George P H Leung
- The University of Hong Kong, Department of Pharmacology, Hong Kong.
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40
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Karran P, Attard N. Thiopurines in current medical practice: molecular mechanisms and contributions to therapy-related cancer. Nat Rev Cancer 2008; 8:24-36. [PMID: 18097462 DOI: 10.1038/nrc2292] [Citation(s) in RCA: 342] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Thiopurines have diverse clinical applications and their long-term use as anti-rejection drugs in transplant patients has been associated with a significantly increased risk of various types of cancer. Although they are slowly being replaced by a new generation of non-thiopurine immunosuppressants, it is anticipated that their use in the management of inflammatory and autoimmune diseases will continue to increase. Therapy-related cancer will remain a potential consequence of prolonged treatment for these generally non-life-threatening conditions. Understanding how thiopurines contribute to the development of cancer will facilitate clinical decisions about the potential risks to patients of long-term treatment for chronic inflammatory disorders.
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Affiliation(s)
- Peter Karran
- Cancer Research UK London Research Institute, Clare Hall Laboratories, South Mimms, Hertfordshire, EN6 3LD, UK.
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41
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Peng XX, Shi Z, Damaraju VL, Huang XC, Kruh GD, Wu HC, Zhou Y, Tiwari A, Fu L, Cass CE, Chen ZS. Up-regulation of MRP4 and down-regulation of influx transporters in human leukemic cells with acquired resistance to 6-mercaptopurine. Leuk Res 2007; 32:799-809. [PMID: 17996297 DOI: 10.1016/j.leukres.2007.09.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Revised: 08/22/2007] [Accepted: 09/27/2007] [Indexed: 11/19/2022]
Abstract
To investigate the mechanism of cellular resistance to 6-MP, we established a 6-MP resistant cell line (CEM-MP5) by stepwise selection of the human T-lymphoblastic leukemia cell line (CEM). CEM-MP5 cells were about 100-fold resistant to 6-MP compared with parental CEM cells. Western blot analysis demonstrated that multidrug resistant protein 4 (MRP4) was increased in CEM-MP5 cells, whereas the levels of the nucleoside transporters hENT1, hCNT2 and hCNT3 were decreased compared with those of parental CEM cells. Consistent with the operation of an efflux pump, accumulation of [14C]6-MP and/or its metabolites was reduced, and ATP-dependent efflux was increased in CEM-MP5 cells. Taken together these results showed that up-regulation of MRP4 and down-regulation of influx transporters played a major role in 6-MP resistance of CEM-MP5 cells.
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Affiliation(s)
- Xing-Xiang Peng
- Department of Pharmaceutical Sciences, College of Pharmacy and Allied Health Professions, St. John's University, Jamaica, NY 11439, United States
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Löffler M, Morote-Garcia JC, Eltzschig SA, Coe IR, Eltzschig HK. Physiological roles of vascular nucleoside transporters. Arterioscler Thromb Vasc Biol 2007; 27:1004-13. [PMID: 17332491 DOI: 10.1161/atvbaha.106.126714] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Nucleoside transporters (NTs) comprise 2 widely expressed families, the equilibrative nucleoside transporters (diffusion-limited channels) and concentrative nucleoside transporters (sodium-dependent transporters). Because of their anatomic position at the blood-tissue interface, vascular NTs are in an ideal position to influence vascular nucleoside levels, particularly adenosine, which among others plays an important role in tissue protection during acute injury. For example, endothelial NTs contribute to preserving the vascular integrity during conditions of limited oxygen availability (hypoxia). Indeed, hypoxia-inducible factor-1-dependent repression of NTs results in enhanced extracellular adenosine signaling and thus attenuates hypoxia-associated increases in vascular leakage. In addition, vascular NTs also contribute to cardiac ischemic preconditioning, coronary vasodilation, and inhibition of platelet aggregation. Moreover, vascular nucleoside uptake via NTs is important for nucleoside recovery, particularly in cells lacking de novo nucleotide synthesis pathways (erythrocytes, leukocytes). Taken together, vascular NTs are critical in modulating adenosine-mediated responses during conditions such as inflammation or hypoxia.
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Affiliation(s)
- Michaela Löffler
- Department of Anesthesiology and Intensive Care Medicine, Tübingen University Hospital, Waldhörnle Str. 22, 72072, Tübingen, Germany
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Nagai K, Nagasawa K, Kihara Y, Okuda H, Fujimoto S. Anticancer nucleobase analogues 6-mercaptopurine and 6-thioguanine are novel substrates for equilibrative nucleoside transporter 2. Int J Pharm 2006; 333:56-61. [PMID: 17088032 DOI: 10.1016/j.ijpharm.2006.09.044] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2006] [Revised: 09/17/2006] [Accepted: 09/26/2006] [Indexed: 01/11/2023]
Abstract
Various antimetabolites of nucleobase analogues, such as 6-mercaptopurine (6-MP), 6-thioguanine (6-TG) and 5-fluorouracil (5-FU), are used for cancer treatments. The first step in nucleobase analogue drug therapy is entry of these compounds into tumor cells. Equilibrative nucleoside transporter 2 (ENT2) was previously reported to have the dual ability of transporting both nucleosides and nucleobases. In the present study, we investigated whether or not these nucleobase analogues are transported via ENT2, using mouse ENT2-overexpressing Cos-7 cells. The hypoxanthine uptake mediated by ENT2 was significantly reduced by the addition of 6-MP and 6-TG, and the inhibition of the hypoxanthine uptake by the 6-thiopurines was competitive. Transfection of ENT2 cDNA into Cos-7 cells resulted in an increase in 6-MP uptake. The 6-MP uptake via ENT2 showed clear time- and substrate concentration-dependent profiles, and was inhibited by 6-TG in an inhibitor concentration-dependent fashion. On the other hand, uracil was not a substrate for ENT2, and 5-FU had no effect on the hypoxanthine uptake via ENT2. Therefore, we concluded that 6-MP and 6-TG, but not 5-FU, are transported mediated by the same recognition site on ENT2 with hypoxanthine.
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Affiliation(s)
- Katsuhito Nagai
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
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Fotoohi AK, Wrabel A, Moshfegh A, Peterson C, Albertioni F. Molecular mechanisms underlying the enhanced sensitivity of thiopurine-resistant T-lymphoblastic cell lines to methyl mercaptopurineriboside. Biochem Pharmacol 2006; 72:816-23. [PMID: 16859645 DOI: 10.1016/j.bcp.2006.06.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2006] [Revised: 06/13/2006] [Accepted: 06/14/2006] [Indexed: 10/24/2022]
Abstract
Methylmercaptopurine riboside (meMPR), a cellular metabolite of 6-mercaptopurine (6-MP), is a potent inhibitor of de novo purine synthesis (DNPS). Human MOLT4 T-lymphoblastic leukaemia cells that have acquired resistance to 6-MP or 6-thioguanine (6-TG) as a consequence of defective transport exhibit enhanced sensitivity to meMPR. HPLC-based analysis of the transport of meMPR revealed normal uptake of this compound by our thiopurine-resistant cell sublines, suggesting a route of transport distinct from that for 6-MP and 6-TG. Studies on the wild-type parental leukemic cells showed that adenosine, dipyridamole and nitrobenzylthioinosine inhibit uptake of meMPR to a significant extent, whereas Na+ ions have no influence on this process. Transfection of these leukemic cells with small interference RNA molecules targeting the gene encoding the first member of the family of equiliberative nucleoside transporters (ENT1) strongly reduced the initial rate of meMPR transport. Our resistant cell lines exhibited 30-52% reductions (p < 0.005) in their levels of mRNA encoding several proteins involved in de novo purine synthesis, i.e., aminoimidazole carboxamide ribonucleotide formyltransferase, glycinamide ribonucleotide transformylase and guanine monophosphate synthetase. Consequently, the rate of de novo purine synthesis in these resistant sublines was decreased by 50%. Furthermore, the levels of ribonucleoside triphosphates in these cells were significantly lower than in the non-resistant parental cells. In combination, a reduced rate of de novo purine synthesis together with low levels of ribonucleoside triphosphates can explain the enhanced sensitivity of our thiopurine-resistant cell lines to meMPR. In this manner, meMPR bypasses the mechanisms of resistance to thiopurines and is even more cytotoxic towards resistant than towards wild-type cells.
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Affiliation(s)
- Alan Kambiz Fotoohi
- Department of Oncology and Pathology, Cancer Center Karolinska (CCK), Karolinska Hospital and Institute, 171 76 Stockholm, Sweden
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