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Bayoumy AB, Ansari AR, Mulder CJJ, Schmiegelow K, Florin T, De Boer NKH. Innovating Thiopurine Therapeutic Drug Monitoring: A Systematic Review and Meta-Analysis on DNA-Thioguanine Nucleotides (DNA-TG) as an Inclusive Biomarker in Thiopurine Therapy. Clin Pharmacokinet 2024; 63:1089-1109. [PMID: 39031224 PMCID: PMC11343975 DOI: 10.1007/s40262-024-01393-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2024] [Indexed: 07/22/2024]
Abstract
BACKGROUND AND OBJECTIVE Thioguanine (TG), azathioprine (AZA), and mercaptopurine (MP) are thiopurine prodrugs commonly used to treat diseases, such as leukemia and inflammatory bowel disease (IBD). 6-thioguanine nucleotides (6-TGNs) have been commonly used for monitoring treatment. High levels of 6-TGNs in red blood cells (RBCs) have been associated with leukopenia, the cutoff levels that predict this side effect remain uncertain. Thiopurines are metabolized and incorporated into leukocyte DNA. Measuring levels of DNA-incorporated thioguanine (DNA-TG) may be a more suitable method for predicting clinical response and toxicities such as leukopenia. Unfortunately, most methodologies to assay 6-TGNs are unable to identify the impact of NUDT15 variants, effecting mostly ethnic populations (e.g., Chinese, Indian, Malay, Japanese, and Hispanics). DNA-TG tackles this problem by directly measuring thioguanine in the DNA, which can be influenced by both TPMT and NUDT15 variants. While RBC 6-TGN concentrations have traditionally been used to optimize thiopurine therapy due to their ease and affordability of measurement, recent developments in liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques have made measuring DNA-TG concentrations in lymphocytes accurate, reproducible, and affordable. The objective of this systematic review was to assess the current evidence of DNA-TG levels as marker for thiopurine therapy, especially with regards to NUDT15 variants. METHODS A systematic review and meta-analysis were performed on the current evidence for DNA-TG as a marker for monitoring thiopurine therapy, including methods for measurement and the illustrative relationship between DNA-TG and various gene variants (such as TPMT, NUDT15, ITPA, NT5C2, and MRP4). PubMed and Embase were systematically searched up to April 2024 for published studies, using the keyword "DNA-TG" with MeSH terms and synonyms. The electronic search strategy was augmented by a manual examination of references cited in articles, recent reviews, editorials, and meta-analyses. A meta-analysis was performed using R studio 4.1.3. to investigate the difference between the coefficients (Fisher's z-transformed correlation coefficient) of DNA-TG and 6-TGNs levels. A meta-analysis was performed using RevMan version 5.4 to investigate the difference in DNA-TG levels between patients with or without leukopenia using randomized effect size model. The risk of bias was assessed using the Newcastle-Ottowa quality assessment scale. RESULTS In this systematic review, 21 studies were included that measured DNA-TG levels in white blood cells for either patients with ALL (n = 16) or IBD (n = 5). In our meta-analysis, the overall mean difference between patients with leukopenia (ALL + IBD) versus no leukopenia was 134.15 fmol TG/µg DNA [95% confidence interval (CI) (83.78-184.35), P < 0.00001; heterogeneity chi squared of 5.62, I2 of 47%]. There was a significant difference in DNA-TG levels for patients with IBD with and without leukopenia [161.76 fmol TG/µg DNA; 95% CI (126.23-197.29), P < 0.00001; heterogeneity chi squared of 0.20, I2 of 0%]. No significant difference was found in DNA-TG level between patients with ALL with or without leukopenia (57.71 fmol TG/µg DNA [95% CI (- 22.93 to 138.35), P < 0.80]). DNA-TG monitoring was found to be a promising method for predicting relapse rates in patients with ALL, and DNA-TG levels are likely a better predictor for leukopenia in patients with IBD than RBC 6-TGNs levels. DNA-TG levels have been shown to correlate with various gene variants (TPMT, NUDT15, ITPA, and MRP4) in various studies, points to its potential as a more informative marker for guiding thiopurine therapy across diverse genetic backgrounds. CONCLUSIONS This systematic review strongly supports the further investigation of DNA-TG as a marker for monitoring thiopurine therapy. Its correlation with treatment outcomes, such as relapse-free survival in ALL and the risk of leukopenia in IBD, underscores its role in enhancing personalized treatment approaches. DNA-TG effectively identifies NUDT15 variants and predicts late leukopenia in patients with IBD, regardless of their NUDT15 variant status. The recommended threshold for late leukopenia prediction in patients with IBD with DNA-TG is suggested to be between 320 and 340 fmol/µg DNA. More clinical research on DNA-TG implementation is mandatory to improve patient care and to improve inclusivity in thiopurine treatment.
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Affiliation(s)
- Ahmed B Bayoumy
- Department of Internal Medicine, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, The Netherlands.
| | - A R Ansari
- Department of Gastroenterology and Hepatology, London Bridge Hospital, London, UK
| | - C J J Mulder
- Department of Gastroenterology and Hepatology, AGEM Research Institute, Amsterdam University Medical Center, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - K Schmiegelow
- Department of Pediatrics and Adolescent Medicine, The Juliane Marie Centre, The University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Clinical Medicine, The Faculty of Health Sciences, The University of Copenhagen, Copenhagen, Denmark
| | - Timothy Florin
- Mater Research, University of Queensland, Translational Research Institute, Woolloongabba, QLD, 4102, Australia
| | - N K H De Boer
- Department of Gastroenterology and Hepatology, AGEM Research Institute, Amsterdam University Medical Center, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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2
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Maillard M, Nishii R, Yang W, Hoshitsuki K, Chepyala D, Lee SHR, Nguyen JQ, Relling MV, Crews KR, Leggas M, Singh M, Suang JLY, Yeoh AEJ, Jeha S, Inaba H, Pui CH, Karol SE, Trehan A, Bhatia P, Antillon Klussmann FG, Bhojwani D, Haidar CE, Yang JJ. Additive effects of TPMT and NUDT15 on thiopurine toxicity in children with acute lymphoblastic leukemia across multiethnic populations. J Natl Cancer Inst 2024; 116:702-710. [PMID: 38230823 PMCID: PMC11077315 DOI: 10.1093/jnci/djae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 12/22/2023] [Accepted: 01/04/2024] [Indexed: 01/18/2024] Open
Abstract
BACKGROUND Thiopurines such as mercaptopurine (MP) are widely used to treat acute lymphoblastic leukemia (ALL). Thiopurine-S-methyltransferase (TPMT) and Nudix hydrolase 15 (NUDT15) inactivate thiopurines, and no-function variants are associated with drug-induced myelosuppression. Dose adjustment of MP is strongly recommended in patients with intermediate or complete loss of activity of TPMT and NUDT15. However, the extent of dosage reduction recommended for patients with intermediate activity in both enzymes is currently not clear. METHODS MP dosages during maintenance were collected from 1768 patients with ALL in Singapore, Guatemala, India, and North America. Patients were genotyped for TPMT and NUDT15, and actionable variants defined by the Clinical Pharmacogenetics Implementation Consortium were used to classify patients as TPMT and NUDT15 normal metabolizers (TPMT/NUDT15 NM), TPMT or NUDT15 intermediate metabolizers (TPMT IM or NUDT15 IM), or TPMT and NUDT15 compound intermediate metabolizers (TPMT/NUDT15 IM/IM). In parallel, we evaluated MP toxicity, metabolism, and dose adjustment using a Tpmt/Nudt15 combined heterozygous mouse model (Tpmt+/-/Nudt15+/-). RESULTS Twenty-two patients (1.2%) were TPMT/NUDT15 IM/IM in the cohort, with the majority self-reported as Hispanics (68.2%, 15/22). TPMT/NUDT15 IM/IM patients tolerated a median daily MP dose of 25.7 mg/m2 (interquartile range = 19.0-31.1 mg/m2), significantly lower than TPMT IM and NUDT15 IM dosage (P < .001). Similarly, Tpmt+/-/Nudt15+/- mice displayed excessive hematopoietic toxicity and accumulated more metabolite (DNA-TG) than wild-type or single heterozygous mice, which was effectively mitigated by a genotype-guided dose titration of MP. CONCLUSION We recommend more substantial dose reductions to individualize MP therapy and mitigate toxicity in TPMT/NUDT15 IM/IM patients.
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Affiliation(s)
- Maud Maillard
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Rina Nishii
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Wenjian Yang
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Keito Hoshitsuki
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Divyabharathi Chepyala
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Shawn H R Lee
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
- Khoo Teck Puat-National University Children’s Medical Institute, National University Hospital, National University Health System, Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Jenny Q Nguyen
- Personalized Care Program, Children’s Hospital Los Angeles, Los Angeles, CA, USA
| | - Mary V Relling
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Kristine R Crews
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Mark Leggas
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Meenu Singh
- Haematology-Oncology Unit, Department of Paediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Joshua L Y Suang
- Khoo Teck Puat-National University Children’s Medical Institute, National University Hospital, National University Health System, Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Allen E J Yeoh
- Khoo Teck Puat-National University Children’s Medical Institute, National University Hospital, National University Health System, Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Sima Jeha
- Department of Oncology, St Jude Children’s Research Hospital, Memphis, TN, USA
- Department of Global Pediatric Medicine, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Hiroto Inaba
- Department of Oncology, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Ching-Hon Pui
- Department of Oncology, St Jude Children’s Research Hospital, Memphis, TN, USA
- Department of Global Pediatric Medicine, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Seth E Karol
- Department of Oncology, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Amita Trehan
- Haematology-Oncology Unit, Department of Paediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Prateek Bhatia
- Haematology-Oncology Unit, Department of Paediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | | | - Deepa Bhojwani
- Cancer and Blood Disease Institute, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Cyrine E Haidar
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Jun J Yang
- Department of Pharmacy and Pharmaceutical Sciences, St Jude Children’s Research Hospital, Memphis, TN, USA
- Department of Oncology, St Jude Children’s Research Hospital, Memphis, TN, USA
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Nazerai L, Willis SC, Yankilevich P, Di Leo L, Bosisio FM, Frias A, Bertolotto C, Nersting J, Thastrup M, Buus S, Thomsen AR, Nielsen M, Rohrberg KS, Schmiegelow K, De Zio D. Thiopurine 6TG treatment increases tumor immunogenicity and response to immune checkpoint blockade. Oncoimmunology 2022; 12:2158610. [PMID: 36545256 PMCID: PMC9762757 DOI: 10.1080/2162402x.2022.2158610] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Immune-checkpoint inhibitors (ICI) are highly effective in reinvigorating T cells to attack cancer. Nevertheless, a large subset of patients fails to benefit from ICI, partly due to lack of the cancer neoepitopes necessary to trigger an immune response. In this study, we used the thiopurine 6-thioguanine (6TG) to induce random mutations and thus increase the level of neoepitopes presented by tumor cells. Thiopurines are prodrugs which are converted into thioguanine nucleotides that are incorporated into DNA (DNA-TG), where they can induce mutation through single nucleotide mismatching. In a pre-clinical mouse model of a mutation-low melanoma cell line, we demonstrated that 6TG induced clinical-grade DNA-TG integration resulting in an improved tumor control that was strongly T cell dependent. 6TG exposure increased the tumor mutational burden, without affecting tumor cell proliferation and cell death. Moreover, 6TG treatment re-shaped the tumor microenvironment by increasing T and NK immune cells, making the tumors more responsive to immune-checkpoint blockade. We further validated that 6TG exposure improved tumor control in additional mouse models of melanoma. These findings have paved the way for a phase I/II clinical trial that explores whether treatment with thiopurines can increase the proportion of otherwise treatment-resistant cancer patients who may benefit from ICI therapy (NCT05276284).
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Affiliation(s)
- Loulieta Nazerai
- Melanoma Research Team, Danish Cancer Society Research Center, Copenhagen, Denmark,Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Shona Caroline Willis
- Melanoma Research Team, Danish Cancer Society Research Center, Copenhagen, Denmark,Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Patricio Yankilevich
- Bioinformatics Core Facility, Instituto de Investigación En Biomedicina de Buenos Aires (Ibioba), Buenos Aires, Argentina
| | - Luca Di Leo
- Melanoma Research Team, Danish Cancer Society Research Center, Copenhagen, Denmark
| | | | - Alex Frias
- Melanoma Research Team, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Corine Bertolotto
- Universite Côte d’Azur, Nice, France,INSERM, Biology and Pathologies of melanocytes, team1, Equipe labellisée Ligue 2020, Centre Méditerranéen de Médecine Moléculaire, Nice, France
| | - Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Maria Thastrup
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Soren Buus
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Allan Randrup Thomsen
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Morten Nielsen
- Department of Health Technology, Section for Bioinformatics, Technical University of Denmark, Lyngby, Denmark
| | | | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Daniela De Zio
- Melanoma Research Team, Danish Cancer Society Research Center, Copenhagen, Denmark,Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark,CONTACT Daniela De Zio Melanoma Research Team, Danish Cancer Society Research Center, Copenhagen, Denmark
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4
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Toksvang LN, Als-Nielsen B, Bacon C, Bertasiute R, Duarte X, Escherich G, Helgadottir EA, Johannsdottir IR, Jónsson ÓG, Kozlowski P, Langenskjöld C, Lepik K, Niinimäki R, Overgaard UM, Punab M, Räty R, Segers H, van der Sluis I, Smith OP, Strullu M, Vaitkevičienė G, Wik HS, Heyman M, Schmiegelow K. Thiopurine Enhanced ALL Maintenance (TEAM): study protocol for a randomized study to evaluate the improvement in disease-free survival by adding very low dose 6-thioguanine to 6-mercaptopurine/methotrexate-based maintenance therapy in pediatric and adult patients (0-45 years) with newly diagnosed B-cell precursor or T-cell acute lymphoblastic leukemia treated according to the intermediate risk-high group of the ALLTogether1 protocol. BMC Cancer 2022; 22:483. [PMID: 35501736 PMCID: PMC9063225 DOI: 10.1186/s12885-022-09522-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/10/2022] [Indexed: 12/05/2022] Open
Abstract
Background A critical challenge in current acute lymphoblastic leukemia (ALL) therapy is treatment intensification in order to reduce the relapse rate in the subset of patients at the highest risk of relapse. The year-long maintenance phase is essential in relapse prevention. The Thiopurine Enhanced ALL Maintenance (TEAM) trial investigates a novel strategy for ALL maintenance. Methods TEAM is a randomized phase 3 sub-protocol to the ALLTogether1 trial, which includes patients 0–45 years of age with newly diagnosed B-cell precursor or T-cell ALL, and stratified to the intermediate risk-high (IR-high) group, in 13 European countries. In the TEAM trial, the traditional methotrexate (MTX)/6-mercaptopurine (6MP) maintenance backbone (control arm) is supplemented with low dose (2.5–12.5 mg/m2/day) oral 6-thioguanine (6TG) (experimental arm), while the starting dose of 6MP is reduced from 75 to 50 mg/m2/day. A total of 778 patients will be included in TEAM during ~ 5 years. The study will close when the last included patient has been followed for 5 years from the end of induction therapy. The primary objective of the study is to significantly improve the disease-free survival (DFS) of IR-high ALL patients by adding 6TG to 6MP/MTX-based maintenance therapy. TEAM has 80% power to detect a 7% increase in 5-year DFS through a 50% reduction in relapse rate. DFS will be evaluated by intention-to-treat analysis. In addition to reducing relapse, TEAM may also reduce hepatotoxicity and hypoglycemia caused by high levels of methylated 6MP metabolites. Methotrexate/6MP metabolites will be monitored and low levels will be reported back to clinicians to identify potentially non-adherent patients. Discussion TEAM provides a novel strategy for maintenance therapy in ALL with the potential of improving DFS through reducing relapse rate. Potential risk factors that have been considered include hepatic sinusoidal obstruction syndrome/nodular regenerative hyperplasia, second cancer, infection, and osteonecrosis. Metabolite monitoring can potentially increase treatment adherence in both treatment arms. Trial registration EudraCT, 2018–001795-38. Registered 2020-05-15, Clinicaltrials.gov, NCT04307576. Registered 2020-03-13, https://clinicaltrials.gov/ct2/show/NCT04307576 Supplementary Information The online version contains supplementary material available at 10.1186/s12885-022-09522-3.
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Affiliation(s)
- Linea Natalie Toksvang
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark.
| | - Bodil Als-Nielsen
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | | | - Ruta Bertasiute
- Vilnius University Hospital Santariskiu Klinikos, Vilnius, Lithuania
| | - Ximo Duarte
- Instituto Português de Oncologia Lisboa Francisco Gentil Departamento de Pediatria, Lisbon, Portugal
| | | | | | | | | | | | | | | | - Riitta Niinimäki
- Oulu University Hospital and PEDEGRO Research Unit, University of Oulu, Oulu, Finland
| | | | - Mari Punab
- Tartu University Hospital, Tartu, Estonia
| | - Riikka Räty
- Helsinki University Central Hospital, Helsinki, Finland
| | - Heidi Segers
- Leuvens Kanker Instituut (LKI), KU Leuven - UZ Leuven, Leuven, Belgium
| | | | | | - Marion Strullu
- Université de Paris, hôpital universitaire Robert-Debré (APHP), Paris, France
| | - Goda Vaitkevičienė
- Center for Pediatric Oncology and Hematology, Vilnius University, Vilnius, Lithuania
| | | | - Mats Heyman
- Karolinska Institutet, Stockholm, Sweden.,Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark.,University of Copenhagen, Copenhagen, Denmark
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5
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Toksvang LN, Grell K, Nielsen SN, Nersting J, Murdy D, Moorman AV, Vora A, Schmiegelow K. DNA-TG and risk of sinusoidal obstruction syndrome in childhood acute lymphoblastic leukemia. Leukemia 2022; 36:555-557. [PMID: 34535761 DOI: 10.1038/s41375-021-01420-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 09/07/2021] [Accepted: 09/08/2021] [Indexed: 01/15/2023]
Affiliation(s)
- Linea Natalie Toksvang
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Kathrine Grell
- Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Stine Nygaard Nielsen
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Daniel Murdy
- Leukaemia Research Cytogenetics Group, Translational and Clinical Research Institute, Newcastle University, Newcastle-upon-Tyne, UK
| | - Anthony V Moorman
- Leukaemia Research Cytogenetics Group, Translational and Clinical Research Institute, Newcastle University, Newcastle-upon-Tyne, UK
| | - Ajay Vora
- Great Ormond Street Hospital for Children National Health Service Trust, London, UK
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark.
- Institute of Clinical Medicine, Faculty of Medicine, University of Copenhagen, Copenhagen, Denmark.
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6
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Toksvang LN, Grell K, Nersting J, Degn M, Nielsen SN, Abrahamsson J, Lund B, Kanerva J, Jónsson ÓG, Lepik K, Vaitkevičienė G, Griškevičius L, Quist-Paulsen P, Vora A, Moorman AV, Murdy D, Zimmermann M, Möricke A, Bostrom B, Joshi J, Hjalgrim LL, Dalhoff KP, Als-Nielsen B, Schmiegelow K. DNA-thioguanine concentration and relapse risk in children and young adults with acute lymphoblastic leukemia: an IPD meta-analysis. Leukemia 2022; 36:33-41. [PMID: 34175901 DOI: 10.1038/s41375-021-01182-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 01/11/2021] [Accepted: 02/02/2021] [Indexed: 12/17/2022]
Abstract
Methotrexate/6-mercaptopurine maintenance therapy improves acute lymphoblastic leukemia (ALL) outcome. Cytotoxicity is mediated by DNA incorporation of thioguanine nucleotides (DNA-TG). We investigated the association of DNA-TG to relapse risk in 1 910 children and young adults with non-high risk ALL. In a cohort-stratified Cox regression analysis adjusted for sex, age, and white cell count at diagnosis, the relapse-specific hazard ratio (HRa) per 100 fmol/μg increase in weighted mean DNA-TG (wmDNA-TG) was 0.87 (95% CI 0.78-0.97; p = 0.013) in the 839 patients who were minimal residual disease (MRD) positive at end of induction therapy (EOI), whereas this was not the case in EOI MRD-negative patients (p = 0.76). Validation analysis excluding the previously published Nordic NOPHO ALL2008 pediatric cohort yielded a HRa of 0.92 (95% CI 0.82-1.03; p = 0.15) per 100 fmol/μg increase in wmDNA-TG in EOI MRD-positive patients. If also excluding the United Kingdom cohort, in which samples were taken non-randomly in selected patients, the HRa for the EOI MRD-positive patients was 0.82 (95% CI 0.68-0.99; p = 0.044) per 100 fmol/μg increase in wmDNA-TG. The importance of DNA-TG as a biomarker for maintenance therapy intensity calls for novel strategies to increase DNA-TG, although its clinical value may vary by protocol backbone.
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Affiliation(s)
| | - Kathrine Grell
- Rigshospitalet, Copenhagen, Denmark
- University of Copenhagen, Copenhagen, Denmark
| | | | | | | | | | - Bendik Lund
- St Olavs Hospital, Trondheim, Norway
- Norwegian University of Science and Technology, Trondheim, Norway
| | - Jukka Kanerva
- Helsinki Central Hospital and University of Helsinki, Helsinki, Finland
| | | | | | - Goda Vaitkevičienė
- Center for Pediatric Oncology and Hematology, Vilnius University, Vilnius, Lithuania
| | - Laimonas Griškevičius
- Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania
- Vilnius University, Vilnius, Lithuania
| | | | - Ajay Vora
- Great Ormond Street Hospital for Children National Health Service Trust, London, United Kingdom
| | - Anthony V Moorman
- Leukaemia Research Cytogenetics Group, Translational and Clinical Research Institute, Newcastle University, Newcastle-upon-Tyne, UK
| | - Daniel Murdy
- Leukaemia Research Cytogenetics Group, Translational and Clinical Research Institute, Newcastle University, Newcastle-upon-Tyne, UK
| | | | - Anja Möricke
- University Hospital Schleswig-Holstein, Kiel, Germany
| | - Bruce Bostrom
- Children's Hospital and Clinics of Minnesota, Minneapolis, MI, USA
| | - Jaitri Joshi
- Children's Hospital and Clinics of Minnesota, Minneapolis, MI, USA
| | | | - Kim P Dalhoff
- University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Pharmacology, Bispebjerg and Frederiksberg University Hospital, Copenhagen, Denmark
| | | | - Kjeld Schmiegelow
- Rigshospitalet, Copenhagen, Denmark.
- University of Copenhagen, Copenhagen, Denmark.
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7
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Somazu S, Tanaka Y, Tamai M, Watanabe A, Kagami K, Abe M, Harama D, Shinohara T, Akahane K, Goi K, Sugita K, Moriyama T, Yang J, Goto H, Minegishi M, Iwamoto S, Takita J, Inukai T. NUDT15 polymorphism and NT5C2 and PRPS1 mutations influence thiopurine sensitivity in acute lymphoblastic leukaemia cells. J Cell Mol Med 2021; 25:10521-10533. [PMID: 34636169 PMCID: PMC8581340 DOI: 10.1111/jcmm.16981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 09/01/2021] [Accepted: 09/26/2021] [Indexed: 12/25/2022] Open
Abstract
In chemotherapy for childhood acute lymphoblastic leukaemia (ALL), maintenance therapy consisting of oral daily mercaptopurine and weekly methotrexate is important. NUDT15 variant genotype is reportedly highly associated with severe myelosuppression during maintenance therapy, particularly in Asian and Hispanic populations. It has also been demonstrated that acquired somatic mutations of the NT5C2 and PRPS1 genes, which are involved in thiopurine metabolism, are detectable in a portion of relapsed childhood ALL. To directly confirm the significance of the NUDT15 variant genotype and NT5C2 and PRPS1 mutations in thiopurine sensitivity of leukaemia cells in the intrinsic genes, we investigated 84 B‐cell precursor‐ALL (BCP‐ALL) cell lines. Three and 14 cell lines had homozygous and heterozygous variant diplotypes of the NUDT15 gene, respectively, while 4 and 2 cell lines that were exclusively established from the samples at relapse had the NT5C2 and PRPS1 mutations, respectively. Both NUDT15 variant genotype and NT5C2 and PRPS1 mutations were significantly associated with DNA‐incorporated thioguanine levels after exposure to thioguanine at therapeutic concentration. Considering the continuous exposure during the maintenance therapy, we evaluated in vitro mercaptopurine sensitivity after 7‐day exposure. Mercaptopurine concentrations lethal to 50% of the leukaemia cells were comparable to therapeutic serum concentration of mercaptopurine. Both NUDT15 variant genotype and NT5C2 and PRPS1 mutations were significantly associated with mercaptopurine sensitivity in 83 BCP‐ALL and 23 T‐ALL cell lines. The present study provides direct evidence to support the general principle showing that both inherited genotype and somatically acquired mutation are crucially implicated in the drug sensitivity of leukaemia cells.
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Affiliation(s)
- Shinpei Somazu
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Yoichi Tanaka
- Department of Clinical Pharmacy, Center for Clinical Pharmacy and Sciences, School of Pharmacy, Kitasato University, Minato-ku, Japan
| | - Minori Tamai
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Atsushi Watanabe
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Keiko Kagami
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Masako Abe
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Daisuke Harama
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Tamao Shinohara
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Koshi Akahane
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Kumiko Goi
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Kanji Sugita
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
| | - Takaya Moriyama
- Department of Pharmaceutical Sciences, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Jun Yang
- Department of Pharmaceutical Sciences, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Hiroaki Goto
- Division of Hematology/Oncology, Kanagawa Children's Medical Center, Kanagawa, Japan
| | | | - Shotaro Iwamoto
- Department of Pediatrics, Mie University Graduate School of Medicine, Tsu, Japan
| | - Junko Takita
- Department of Pediatrics, Kyoto University, Kyoto, Japan
| | - Takeshi Inukai
- Department of Pediatrics, University of Yamanashi, Yamanashi, Japan
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8
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Choi R, Chun MR, Park J, Lee JW, Ju HY, Cho HW, Hyun JK, Koo HH, Yi ES, Lee SY. Quantification of Thioguanine in DNA Using Liquid Chromatography-Tandem Mass Spectrometry for Routine Thiopurine Drug Monitoring in Patients With Pediatric Acute Lymphoblastic Leukemia. Ann Lab Med 2021; 41:145-154. [PMID: 33063676 PMCID: PMC7591283 DOI: 10.3343/alm.2021.41.2.145] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 05/03/2020] [Accepted: 09/19/2020] [Indexed: 12/15/2022] Open
Abstract
Background We developed an assay to measure DNA-incorporated 6-thioguanine (DNA-TG) and validated its clinical applicability in Korean pediatric patients with acute lymphoblastic leukemia (ALL) in order to improve individualized thiopurine treatment and reduce the life-threatening cytotoxicity. Methods The DNA-TG assay was developed based on liquid chromatography-tandem mass spectrometry, with isotope-labeled TG-d3 and guanine-d3 as internal standards. This method was applied to 257 samples of pediatric ALL patients. The DNA-TG level was compared with erythrocyte TG nucleotide (RBC-TGN) level in relation to the TPMT and NUDT15 genotypes, which affect thiopurine metabolism, using Spearman’s rank test and repeated measure ANOVA. Results For DNA-TG quantification, a linearity range of 10.0-5,000.0 fmol TG/µg DNA; bias for accuracy of –10.4% –3.5%; coefficient of variation for intra- and inter-day precision of 3.4% and 5.8% at 80 fmol TG/µg DNA and of 4.9% and 5.3% at 800 fmol TG/µg DNA, respectively; and recovery of 85.7%–116.2% were achieved without matrix effects or carry-over. The median DNA-TG level in the 257 samples was 106.0 fmol TG/µg DNA (interquartile range, 75.8–150.9). There was a strong correlation between DNA-TG and RBC-TGN levels (ρ = 0.68, P < 0.0001). The DNA-TG/RBC-TGN ratio was significantly higher in NUDT15 intermediate metabolizers (*1/*2 and *1/*3) than in patients with wildtype alleles (P < 0.0001). Conclusions This simple and sensitive method for measuring DNA-TG level can improve therapeutic drug monitoring for thiopurine treatment.
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Affiliation(s)
- Rihwa Choi
- Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul, Korea.,Department of Laboratory Medicine, Green Cross Laboratories, Yongin, Korea
| | - Mi Ryung Chun
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Seoul, Korea
| | - Jisook Park
- Samsung Biomedical Research Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ji Won Lee
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hee Young Ju
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hee Won Cho
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ju Kyung Hyun
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hong Hoe Koo
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Eun Sang Yi
- Department of Pediatrics, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea
| | - Soo-Youn Lee
- Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul, Korea.,Department of Laboratory Medicine and Genetics, Samsung Medical Center, Seoul, Korea.,Department of Clinical Pharmacology and Therapeutics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Department of Health Science and Technology, Samsung Advanced Institute of Health Science and Technology, Sungkyunkwan University, Seoul, Korea
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9
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Maintenance therapy and risk of osteonecrosis in children and young adults with acute lymphoblastic leukemia: a NOPHO ALL2008 sub-study. Cancer Chemother Pharmacol 2021; 88:911-917. [PMID: 34145469 DOI: 10.1007/s00280-021-04316-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/07/2021] [Indexed: 12/24/2022]
Abstract
PURPOSE Osteonecrosis is a burdensome treatment-related toxicity that is mostly diagnosed during or soon after 6-mercaptopurine (6MP)/methotrexate (MTX) maintenance therapy for acute lymphoblastic leukemia (ALL), possibly indicating a pathogenic role of these drugs. METHODS We prospectively registered symptomatic osteonecrosis during treatment of 1234 patients aged 1.0-45.9 years treated according to the Nordic Society of Hematology and Oncology (NOPHO) ALL2008 protocol. MTX/6MP metabolites were measured as part of the NOPHO ALL2008 maintenance therapy study. RESULTS After a median follow-up of 5.6 years [interquartile range (IQR) 3.6-7.5], 68 patients had been diagnosed with symptomatic osteonecrosis. The cumulative incidence was 2.7% [95% confidence interval (CI) 1.6-3.8%] for patients aged < 10 years, 14.9% (95% CI 9.7-20.2%) for patients aged 10.0-17.9 years, and 14.4% (95% CI 8.0-20.8%) for patients aged ≥ 18 years. The median time from diagnosis of ALL to diagnosis of osteonecrosis in these age groups was 1.0 year (IQR 0.7-2.0), 2.0 years (IQR 1.1-2.4), and 2.2 years (IQR 1.8-2.8), respectively (p = 0.001). With 17,854 blood samples available for MTX and 6MP metabolite analysis, neither erythrocyte levels of 6-thioguanine (TG) nucleotides (p > 0.99), methylated 6MP metabolites (p = 0.37), MTX polyglutamates (p = 0.98) nor DNA-TG (p = 0.53) were significantly associated with the hazard of osteonecrosis in Cox models stratified by the three age groups and adjusted for sex. CONCLUSION Maintenance therapy intensity determined by 6MP and MTX metabolites was not associated with the risk of developing osteonecrosis in the NOPHO ALL2008 cohort.
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10
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No association between relapse hazard and thiopurine methyltransferase geno- or phenotypes in non-high risk acute lymphoblastic leukemia: a NOPHO ALL2008 sub-study. Cancer Chemother Pharmacol 2021; 88:271-279. [PMID: 33928426 DOI: 10.1007/s00280-021-04281-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/14/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE 6-mercaptopurine(6MP)/methotrexate maintenance therapy is essential to reduce relapse of childhood acute lymphoblastic leukemia (ALL). Common germline variants in TPMT cause low activity of thiopurine methyltransferase (TPMT) and higher 6MP metabolite (TGN) levels. Higher levels of TGNs incorporated into DNA (DNA-TG) and low TPMT activity have previously been associated with a lower relapse risk. We explored if TPMT geno- or phenotype was associated with DNA-TG levels and relapse rate in NOPHO ALL2008. METHODS TPMT genotype, repeated phenotyping, and DNA-TG measurements were collected in 918 children with non-high risk ALL (NOPHO ALL2008 maintenance therapy study). Maintenance therapy started with 6MP at 50 and 75 mg/m2 for TPMT heterozygous and wildtype patients and was adjusted to a target WBC of 1.5 - 3.0 × 109/L. RESULTS Of 918 patients, 78 (8.5%) were TPMT heterozygous and 903 had at least one TPMT measurement (total 3063). Mean TPMT activities were higher with wildtype than heterozygous TPMT (N = 752, 16.6 versus 9.6 U/mL ery., p < 0.001). The 5-year cumulative incidence of relapse was 6.4% and 6.0% for TPMT heterozygous and wildtype patients, and there was no association between genotype and relapse rate (N = 918, hazard ratio = 1.01, 95% confidence interval [CI] 0.40 - 2.54, p = 0.98). Although TPMT heterozygous patients had higher DNA-TG (N = 548, median 760.9 [interquartile range (IQR) 568.7 - 890.3] versus 492.7 [IQR 382.1 - 634.6] fmol/µg, p < 0.001), TPMT activity was not associated with relapse rate (N = 813; hazard ratio = 0.98 per one U/mL ery. increase in TPMT activity, 95% CI 0.91 - 1.06, p = 0.67). CONCLUSION TPMT geno- and phenotype were not associated with relapse in non-high risk NOPHO ALL2008.
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11
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Dreisig K, Brünner ED, Marquart HV, Helt LR, Nersting J, Frandsen TL, Jonsson OG, Taskinen M, Vaitkeviciene G, Lund B, Abrahamsson J, Lepik K, Schmiegelow K. TPMT polymorphisms and minimal residual disease after 6-mercaptopurine post-remission consolidation therapy of childhood acute lymphoblastic leukaemia. Pediatr Hematol Oncol 2021; 38:227-238. [PMID: 33205673 DOI: 10.1080/08880018.2020.1842570] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Bone marrow minimal residual disease (MRD) is the strongest predictor of relapse in children with acute lymphoblastic leukemia (ALL). 6-mercaptopurine (6MP) in ALL therapy has wide inter-individual variation in disposition and is strongly influenced by polymorphisms in the thiopurine methyltransferase (TPMT) gene. In 952 patients treated according to the NOPHO ALL2008 protocol, we explored the association between thiopurine disposition, TPMT genotypes and MRD levels after consolidation therapy with 6MP, high-dose methotrexate (HD-MTX), asparaginase, and vincristine. The levels of the cytotoxic DNA-incorporated thioguanine were significantly higher on day 70-79 in G460A/A719G TPMT heterozygous (TPMTHZ) compared to TPMT wild type (TPMTWT) patients (mean: 230.7 vs. 149.7 fmol/µg DNA, p = 0.002). In contrast, TPMT genotype did not associate with the end of consolidation MRD levels irrespective of randomization of the patients to fixed dose (25 mg/m2/day) or 6MP escalation (up to 50 or 75 mg/m2/day) during consolidation therapy.
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Affiliation(s)
- Karin Dreisig
- Pediatric Oncology research laboratory, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Emilie Damgaard Brünner
- Pediatric Oncology research laboratory, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Hanne V Marquart
- The Tissue Typing Laboratory, Department of Clinical Immunology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Louise Rold Helt
- Pediatric Oncology research laboratory, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Jacob Nersting
- Pediatric Oncology research laboratory, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Thomas Leth Frandsen
- Department of Pediatrics and adolescent medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | | | - Mervi Taskinen
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Children and Adolescents, Helsinki University Hospital, Helsinki, Finland
| | - Goda Vaitkeviciene
- Children's Hospital, Vilnius University Hospital Santaros Klinikos and Vilnius University, Vilnius, Lithuania
| | - Bendik Lund
- Department of Pediatrics, St. Olavs Hospital, Trondheim; Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Jonas Abrahamsson
- Department of Pediatrics, Institution for Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | | | - Kjeld Schmiegelow
- Pediatric Oncology research laboratory, The University Hospital Rigshospitalet, Copenhagen, Denmark.,Department of Pediatrics and adolescent medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark.,Institute of Clinical Medicine, Faculty of Medicine, University of Copenhagen, Denmark
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12
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Dynamics of leucocyte DNA thioguanine nucleotide levels during maintenance therapy of childhood acute lymphoblastic leukemia. Cancer Chemother Pharmacol 2021; 88:53-60. [PMID: 33754188 DOI: 10.1007/s00280-020-04219-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/20/2020] [Indexed: 10/21/2022]
Abstract
PURPOSE Methotrexate (MTX)/6-Mercaptopurine (6MP)-based maintenance therapy is crucial to cure childhood acute lymphoblastic leukemia (ALL). Cytotoxicity is mediated by incorporation of thioguanine nucleotides (TGN) into DNA (DNA-TG) with higher levels in leucocytes being associated with reduced relapse risk. To further understand the dynamics of DNA-TG formation, we measured DNA-TG levels in leucocyte subsets during maintenance therapy and in the months following its discontinuation. METHODS DNA-TG levels were measured in leucocytes (DNA-TGTotal), polymorph nucleated granulocytes (neutrophils, eosinophils, basophils [DNA-TGPMN]) and mononucleated cells (lymphocytes, monocytes [DNA-TGMNC]) in 1013 samples from 52 patients on ALL maintenance therapy (951 samples during therapy and 62 samples after therapy discontinuation, respectively). RESULTS Median DNA-TGTotal, DNA-TGPMN and DNA-TGMNC during maintenance therapy were 539, 563 and 384 fmol/µg DNA, respectively. DNA-TGPMN displayed more pronounced fluctuation than DNA-TGMNC (range 0-3084 [interquartile range IQR 271-881] versus 30-1411 [IQR 270-509] fmol/µg DNA). DNA-TGTotal was more strongly correlated with DNA-TGPMN (rS = 0.95, p < 0.0001) than DNA-TGMNC (rS = 0.73, p < 0.0001). DNA-TGPMN correlated less with DNA-TGMNC (rS = 0.64, p < 0.0001) and to a much lesser extent with absolute neutrophil count (rS = 0.35, p < 0.0001). Following discontinuation of therapy, DNA-TGPMN was rapidly eliminated, and not measurable beyond day 22 after discontinuation, whereas DNA-TGMNC was slowly eliminated, and five patients demonstrated a measurable DNA-TGMNC more than 365 days after therapy discontinuation. CONCLUSION Fluctuations in DNA-TGTotal are predominantly caused by corresponding fluctuations in DNA-TGPMN, thus DNA-TGTotal measures recent TGN incorporation in these short-lived cells. Measurement of DNA-TGTotal at 2-4 weeks intervals provides a reliable profile of DNA-TG levels.
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13
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Effects of germline DHFR and FPGS variants on methotrexate metabolism and relapse of leukemia. Blood 2021; 136:1161-1168. [PMID: 32391884 DOI: 10.1182/blood.2020005064] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/23/2020] [Indexed: 12/12/2022] Open
Abstract
Methotrexate (MTX) during maintenance therapy is essential for curing acute lymphoblastic leukemia (ALL), but dosing strategies aiming at adequate treatment intensity are challenged by interindividual differences in drug disposition. To evaluate genetic factors associated with MTX metabolism, we performed a genome-wide association study in 447 ALL cases from the Nordic Society for Pediatric Haematology and Oncology ALL2008 study, validating results in an independent set of 196 patients. The intergenic single-nucleotide polymorphism rs1382539, located in a regulatory element of DHFR, was associated with increased levels of short-chain MTX polyglutamates (P = 1.1 × 10-8) related to suppression of enhancer activity, whereas rs35789560 in FPGS (p.R466C, P = 5.6 × 10-9) was associated with decreased levels of long-chain MTX polyglutamates through reduced catalytic activity. Furthermore, the FPGS variant was linked with increased relapse risk (P = .044). These findings show a genetic basis for interpatient variability in MTX response and could be used to improve future dosing algorithms.
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14
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Wu M, Kumar A. Pt-decorated graphene-like AlN nanosheet as a biosensor for tioguanine drug: A computational study. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2020.112976] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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15
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Choi R, Lee MN, Kim K, Baek SY, Kim TJ, Hong SN, Kim YH, Lee SY. Effects of various genetic polymorphisms on thiopurine treatment-associated outcomes for Korean patients with Crohn's disease. Br J Clin Pharmacol 2020; 86:2302-2313. [PMID: 32372428 DOI: 10.1111/bcp.14339] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/31/2020] [Accepted: 04/13/2020] [Indexed: 12/23/2022] Open
Abstract
AIMS This study explores the effects of various genetic polymorphisms in candidate genes on thiopurine metabolism and toxicity in adult patients with Crohn's disease in Korea. METHODS A total of 131 adult patients with Crohn's disease receiving thiopurine treatment were included. The TPMT and NUDT15 genes and an additional 116 genetic polymorphisms (in 40 genes and 3 intergenic locations) were screened for genotyping. Among the polymorphisms screened, 91 genetic polymorphisms (in 34 genes and 3 intergenic locations) in addition to TPMT and NUDT15 genotypes were included for statistical analyses to investigate their effects on thiopurine metabolites and adverse outcomes (leukopenia, hepatotoxicity, gastrointestinal intolerance, skin rash and alopecia). RESULTS The median duration of thiopurine treatment was 47.0 months (range 6.0-153.4 months). Patient sex, maintenance dose of thiopurine, and use of anti-tumour necrosis factor agents were associated with thiopurine metabolite concentrations (P < .05). In the univariate analysis, the TPMT genotype was associated with 6-thioguanine level (P < .05), although the significance of this did not remain in multivariate analysis. Genetic polymorphisms in the ATIC (rs3821353 and rs16853834), IMPDH2 (rs11706052) and ITPA (rs6139036) genes were associated with thiopurine metabolism (P < .05). Genetic polymorphisms in the ABCC5 (rs8180093) and NUDT15 genotypes were associated with leukopenia (P < .05). CONCLUSION The results of this study may help clinicians to understand the effects of other various polymorphisms in addition to TPMT and NUDP15 in thiopurine metabolism for management of Crohn's disease patients.
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Affiliation(s)
- Rihwa Choi
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Department of Laboratory Medicine, Green Cross Laboratories, Yongin, Gyeonggi, Republic of Korea
| | - Mi-Na Lee
- Department of Laboratory Medicine, Green Cross Laboratories, Yongin, Gyeonggi, Republic of Korea
| | - Kyunga Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Sun-Young Baek
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Tae Jun Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sung Noh Hong
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Young-Ho Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Soo-Youn Lee
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Department of Clinical Pharmacology and Therapeutics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
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16
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17
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Shpigun LK, Andryukhina EY. A New Electrochemical Sensor for Direct Detection of Purine Antimetabolites and DNA Degradation. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2019; 2019:1572526. [PMID: 30984441 PMCID: PMC6431463 DOI: 10.1155/2019/1572526] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/07/2019] [Accepted: 02/11/2019] [Indexed: 06/09/2023]
Abstract
The development of a reliable electrochemical sensor using a hybrid nanocomposite consisting of ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) functionalized graphene oxide (GrO-IL) and gold nanoparticles (AuNPs) stabilized by chitosan (Chit) was described. The new sensor, labelled as GrO-IL-AuNPs-Chit/CSE, exhibited an improved electrocatalytic response to cancer drugs such as purine antimetabolites (6-thioguanine, 6-mercaptopurine, and azathioprine) in a wide concentration range with a low detection limit (20-40 nmol·L-1, S/N = 3), and satisfactory recoveries (97.1-103.0%). The sensor has been also successfully used for cyclic voltammetric study of a salmon sperm double-stranded DNA degradation and DNA-6-mercaptopurine interaction in aqueous solutions (pH 7.4).
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Affiliation(s)
- Liliya K. Shpigun
- Institute of General & Inorganic Chemistry of Russian Academy of Sciences, 119991 Moscow, Russia
| | - Elena Yu. Andryukhina
- Institute of General & Inorganic Chemistry of Russian Academy of Sciences, 119991 Moscow, Russia
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18
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Grosen A, Nersting J, Bungum M, Christensen LA, Schmiegelow K, Spanò M, Julsgaard M, Cordelli E, Leter G, Larsen PB, Hvas CL, Kelsen J. Sperm DNA Integrity is Unaffected by Thiopurine Treatment in Men With Inflammatory Bowel Disease. J Crohns Colitis 2019; 13:3-11. [PMID: 29917107 DOI: 10.1093/ecco-jcc/jjy086] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND AIMS Sperm DNA integrity, concentration, and motility are suspected to be altered by thiopurines (azathioprine [AZA] and 6-mercaptopurine [6-MP]). We investigated the impact of thiopurines on semen quality in men with inflammatory bowel disease [IBD], by a comprehensive panel of semen analyses. METHODS Semen from 40 men with IBD, in remission on AZA/6-MP therapy, was prospectively collected and compared with samples from 40 healthy volunteers. Paired samples [off and on AZA/6-MP] were obtained from a subset of IBD patients, and blood and semen were collected to determine 6-MP transmission to the ejaculate. Sperm DNA fragmentation was evaluated via sperm chromatin structure assay [SCSA] and Comet analysis. Conventional World Health Organization [WHO] parameters, i.e. semen volume and sperm concentration, motility, and morphology, were assessed. Additionally, we measured thioguanine nucleotide [TGN] incorporation in sperm cell DNA. RESULTS Sperm DNA fragmentation levels did not differ between men with IBD on AZA/6-MP and healthy volunteers when evaluated by SCSA [p = 0.23] and Comet analysis [p = 0.72]. IBD patients on AZA/6-MP had significantly lower total and progressive sperm motility than healthy volunteers [48.5% versus 64.5%, p = 0.0003; 27.4% versus 43.3%, p = 0.0004; respectively], with no differences in concentration, volume, or morphology. The same trend was observed in the 10 paired samples. TGN incorporation was not detectable in sperm DNA, but 6-MP was detected in seminal plasma and correlated to blood levels [rs = 0.79, p = 0.02]. CONCLUSIONS Thiopurines do not increase sperm DNA fragmentation but may impair sperm motility in this IBD cohort. Our findings support existing epidemiological data that thiopurine therapy is safe during preconception and should not be abandoned.
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Affiliation(s)
- Anne Grosen
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | - Jacob Nersting
- Department of Paediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Mona Bungum
- Reproductive Medicine Centre [RMC], Skaane University Hospital, Malmoe, Sweden
| | - Lisbet Ambrosius Christensen
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark.,Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Kjeld Schmiegelow
- Department of Paediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Marcello Spanò
- Laboratory of Biosafety and Risk Assessment, Division of Health Protection Technologies, ENEA [Italian National Agency for New Technologies, Energy and Sustainable Development], Casaccia Research Center, Rome, Italy
| | - Mette Julsgaard
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | - Eugenia Cordelli
- Laboratory of Biosafety and Risk Assessment, Division of Health Protection Technologies, ENEA [Italian National Agency for New Technologies, Energy and Sustainable Development], Casaccia Research Center, Rome, Italy
| | - Giorgio Leter
- Laboratory of Biosafety and Risk Assessment, Division of Health Protection Technologies, ENEA [Italian National Agency for New Technologies, Energy and Sustainable Development], Casaccia Research Center, Rome, Italy
| | | | - Christian Lodberg Hvas
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | - Jens Kelsen
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
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19
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Zaidi SA. Effective imprinting of an anticancer drug, 6-thioguanine,viamussel-inspired self-polymerization of dopamine over reduced graphene oxide. Analyst 2019; 144:2345-2352. [DOI: 10.1039/c8an02348d] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Apart from being a vital catecholamine molecule responsible for the proper functioning of the central nervous system (CNS), hormonal and renal systems, dopamine (DA) has also been increasingly employed as a functional monomer in the fabrication of surface molecular imprinting polymers (MIPs) for valuable analytes.
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20
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Nersting J, Nielsen SN, Grell K, Paerregaard M, Abrahamsson J, Lund B, Jonsson OG, Pruunsild K, Vaitkeviciene G, Kanerva J, Schmiegelow K. Methotrexate polyglutamate levels and co-distributions in childhood acute lymphoblastic leukemia maintenance therapy. Cancer Chemother Pharmacol 2018; 83:53-60. [PMID: 30324220 DOI: 10.1007/s00280-018-3704-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 10/10/2018] [Indexed: 01/14/2023]
Abstract
PURPOSE Methotrexate polyglutamates (MTXpg) facilitate incorporation of thioguanine nucleotides into DNA (DNA-TG, the primary cytotoxic thiopurine metabolite and outcome determinant in MTX/6-mercaptopurine treatment of childhood ALL). We hypothesized that mapping erythrocyte levels of MTXpg with 1-6 glutamates and their associations with DNA-TG formation would facilitate future guidelines for maintenance therapy dosing. METHODS AND RESULTS Summed MTX with 1-6 glutamates resolved by LCMS [median (interquartile): 5.47 (3.58-7.69) nmol/mmol hemoglobin] was in agreement with total MTX by radio ligand assay. In 16,389 blood samples from 1426 ALL maintenance therapy patients, MTXpg3 21.0 (15.2-27.4)% was the predominant metabolite, and MTXpg1 (the maternal drug) constituted 38.6 (27.2-50.2)% of MTXpg1-6. All subsets correlated; the strongest associations were between metabolites with similar polyglutamate lengths. Correlations of MTXpg1 with MTXpg2 and MTXpg3,4,5,6 were rs = 0.68 and rs = 0.25-0.42, respectively. Intercorrelations of MTXpg3,4,5,6 were all rs ≥ 0.51. MTXpg4 accounted for 29.8 (24.7-33.3)% of MTXpg3-6, yet explained 96% of the summed MTXpg3-6 variation. MTXpg1-4, MTXpg1-6, MTXpg2-6 and MTXpg3 were all associated with DNA-TG levels (p < 0.00001), but collinearity precluded identification of the most informative subset. CONCLUSIONS Measuring erythrocyte MTXpg4 simplifies and can replace longer chain MTXpg monitoring. Resolving individual MTXpg identifies samples that are unsuitable for dose guidance due to high levels of MTXpg1 remaining in the plasma fraction because of recent MTX intake. All tested MTXpg subsets correlated with DNA-TG and may be used for ALL maintenance therapy dose adjustments, but the most informative subset remains to be identified.
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Affiliation(s)
- Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.
| | - Stine Nygaard Nielsen
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Kathrine Grell
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.,Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Maria Paerregaard
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Jonas Abrahamsson
- Department of Pediatrics, Institution for Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Bendik Lund
- Department of Pediatrics, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
| | | | | | | | - Jukka Kanerva
- Children's Hospital, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
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21
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Tulstrup M, Grosjean M, Nielsen SN, Grell K, Wolthers BO, Wegener PS, Jonsson OG, Lund B, Harila-Saari A, Abrahamsson J, Vaitkeviciene G, Pruunsild K, Toft N, Holm M, Hulegårdh E, Liestøl S, Griskevicius L, Punab M, Wang J, Carroll WL, Zhang Z, Dalgaard MD, Gupta R, Nersting J, Schmiegelow K. NT5C2 germline variants alter thiopurine metabolism and are associated with acquired NT5C2 relapse mutations in childhood acute lymphoblastic leukaemia. Leukemia 2018; 32:2527-2535. [PMID: 30201983 DOI: 10.1038/s41375-018-0245-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/12/2018] [Accepted: 07/19/2018] [Indexed: 12/18/2022]
Abstract
The antileukaemic drug 6-mercaptopurine is converted into thioguanine nucleotides (TGN) and incorporated into DNA (DNA-TG), the active end metabolite. In a series of genome-wide association studies, we analysed time-weighted means (wm) of erythrocyte concentrations of TGN (Ery-TGN) and DNA-TG in 1009 patients undergoing maintenance therapy for acute lymphoblastic leukaemia (ALL). In discovery analyses (454 patients), the propensity for DNA-TG incorporation (wmDNA-TG/wmEry-TGN ratio) was significantly associated with three intronic SNPs in NT5C2 (top hit: rs72846714; P = 2.09 × 10-10, minor allele frequency 15%). In validation analyses (555 patients), this association remained significant during both early and late maintenance therapy (P = 8.4 × 10-6 and 1.3 × 10-3, respectively). The association was mostly driven by differences in wmEry-TGN, but in regression analyses adjusted for wmEry-TGN (P < 0.0001), rs72846714-A genotype was also associated with a higher wmDNA-TG (P = 0.029). Targeted sequencing of NT5C2 did not identify any missense variants associated with rs72846714 or wmEry-TGN/wmDNA-TG. rs72846714 was not associated with relapse risk, but in a separate cohort of 180 children with relapsed ALL, rs72846714-A genotype was associated with increased occurrence of relapse-specific NT5C2 gain-of-function mutations that reduce cytosol TGN levels (P = 0.03). These observations highlight the impact of both germline and acquired mutations in drug metabolism and disease trajectory.
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Affiliation(s)
- Morten Tulstrup
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Marie Grosjean
- Department of Bio and Health Informatics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Stine Nygaard Nielsen
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Kathrine Grell
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark.,Section of Biostatistics, Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Benjamin Ole Wolthers
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Peder Skov Wegener
- Department of Pediatric Hematology and Oncology, H. C. Andersen Children's Hospital, Odense University Hospital, Odense, Denmark
| | | | - Bendik Lund
- Department of Pediatrics, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.,Department of Laboratory Medicine, Faculty of Medicine and Health sciences, Children's and Women's Health, Norwegian University of Science and Technology, Trondheim, Norway
| | - Arja Harila-Saari
- Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden
| | - Jonas Abrahamsson
- Department of Pediatrics, Institution for Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Goda Vaitkeviciene
- Clinic of Children's Diseases, Faculty of Medicine, Vilnius University, Vilnius, Lithuania
| | - Kaie Pruunsild
- Department of Onco-haematology, Talinn Children's Hospital, Talinn, Estonia
| | - Nina Toft
- Department of Hematology, University Hospital Rishospitalet, Copenhagen, Denmark
| | - Mette Holm
- Department of Haematology, Aarhus University Hospital, Aarhus, Denmark
| | - Erik Hulegårdh
- Department of Hematology and Coagulation, Sahlgrenska University Hospital, Göteborg, Sweden
| | - Sigurd Liestøl
- Department of Hematology, Ullevål University Hospital, Faculty Division Ullevål University Hospital, University of Oslo, Oslo, Norway
| | - Laimonas Griskevicius
- Institute of Clinical Medicine, Faculty of Medicine, Vilnius University, Vilnius, Lithuania.,Hematology, Oncology and Transfusion Medicine Center, Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania
| | - Mari Punab
- Clinic of Hematology and Oncology, Tartu University Clinic, Tartu, Estonia
| | - Jinhua Wang
- Masonic Cancer Center, Institute for Health Informatics, University of Minnesota, Minneapolis, MN, USA
| | - William L Carroll
- Department of Pediatrics, New York University Medical Center, Perlmutter Cancer Center, New York, NY, USA
| | - Zeyu Zhang
- Department of Bio and Health Informatics, Technical University of Denmark, Kongens Lyngby, Denmark.,Sino-Danish Center for Education and Research, University of Chinese Academy of Sciences, Beijing, China
| | - Marlene D Dalgaard
- Department of Bio and Health Informatics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Ramneek Gupta
- Department of Bio and Health Informatics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark. .,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
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22
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The effects of inherited NUDT15 polymorphisms on thiopurine active metabolites in Japanese children with acute lymphoblastic leukemia. Pharmacogenet Genomics 2018; 27:236-239. [PMID: 28445187 DOI: 10.1097/fpc.0000000000000282] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Thiopurines [e.g. mercaptopurine (MP)] are widely used as chemotherapeutic agents in the treatment of pediatric acute lymphoblastic leukemia with dose-limiting hematopoietic toxicity. Recently, germline variants in NUDT15 have been identified as a major genetic cause for MP-related bone marrow suppression, and there is increasing interest in the clinical implementation of NUDT15 genotype-guided MP dose individualization. Therefore, we sought to evaluate the effects of NUDT15 on thiopurine metabolism and identify pharmacologic markers to inform NUDT15 genotype-guided MP dosing. In 55 Japanese children with acute lymphoblastic leukemia, we simultaneously measured both thioguanine nucleotides (TGN) in red blood cells and DNA-incorporated thioguanine (DNA-TG) in white blood cells. TGN levels were significantly lower in patients with NUDT15 deficiency, likely because of toxicity-related MP dose reduction. In contrast, when exposed to the same dose of MP, DNA-TG accumulated more efficiently in vivo with increasing number of risk alleles in NUDT15 (P=4.0×10). Cytosolic TGN and nuclear DNA-TG were correlated positively with each other across genotype groups (P=6.5×10), but the ratio of DNA-TG to TGN was significantly higher in NUDT15-deficient patients (P=3.6×10), consistent with excessive MP activation. In conclusion, our results suggest that DNA-TG is a more relevant MP metabolite than TGN to inform NUDT15 genotype-guided dose adjustments.
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23
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Preclinical evaluation of NUDT15-guided thiopurine therapy and its effects on toxicity and antileukemic efficacy. Blood 2018; 131:2466-2474. [PMID: 29572377 DOI: 10.1182/blood-2017-11-815506] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 03/14/2018] [Indexed: 01/18/2023] Open
Abstract
Thiopurines (eg, 6-mercaptopurine [MP]) are highly efficacious antileukemic agents, but they are also associated with dose-limiting toxicities. Recent studies by us and others have identified inherited NUDT15 deficiency as a novel genetic cause of thiopurine toxicity, and there is a strong rationale for NUDT15-guided dose individualization to preemptively mitigate adverse effects of these drugs. Using CRISPR-Cas9 genome editing, we established a Nudt15-/- mouse model to evaluate the effectiveness of this strategy in vivo. Across MP dosages, Nudt15-/- mice experienced severe leukopenia, rapid weight loss, earlier death resulting from toxicity, and more bone marrow hypocellularity compared with wild-type mice. Nudt15-/- mice also showed excessive accumulation of a thiopurine active metabolite (ie, DNA-incorporated thioguanine nucleotides [DNA-TG]) in an MP dose-dependent fashion, as a plausible cause of increased toxicity. MP dose reduction effectively normalized systemic exposure to DNA-TG in Nudt15-/- mice and largely eliminated Nudt15 deficiency-mediated toxicity. In 95 children with acute lymphoblastic leukemia, MP dose adjustment also directly led to alteration in DNA-TG levels, the effects of which were proportional to the degree of NUDT15 deficiency. Using leukemia-bearing mice with concordant Nudt15 genotype in leukemia and host, we also confirmed that therapeutic efficacy was preserved in Nudt15-/- mice receiving a reduced MP dose compared with Nudt15+/+ counterparts exposed to a standard dose. In conclusion, we demonstrated that NUDT15 genotype-guided MP dose individualization can preemptively mitigate toxicity without compromising therapeutic efficacy.
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24
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Gerbek T, Ebbesen M, Nersting J, Frandsen TL, Appell ML, Schmiegelow K. Role of TPMT and ITPA variants in mercaptopurine disposition. Cancer Chemother Pharmacol 2018; 81:579-586. [PMID: 29387964 DOI: 10.1007/s00280-018-3525-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 01/18/2018] [Indexed: 12/21/2022]
Abstract
PURPOSE To explore the levels of thioguanine incorporated into DNA (DNA-TG), and erythrocyte levels of 6-thioguanine nucleotides (Ery-TGN) and methylated metabolites (Ery-MeMP) during 6-mercaptopurine (6MP)/Methotrexate (MTX) therapy of childhood acute lymphoblastic leukemia (ALL) and the relation to inosine triphosphatase (ITPA) and thiopurine methyltransferase (TPMT) gene variants. METHODS Blood samples were drawn during 6MP/MTX maintenance therapy from 132 children treated for ALL at Rigshospitalet, Copenhagen. The samples were analysed for thiopurine metabolites and compared to TPMT (rs1800460 and rs1142345) and ITPA (rs1127354) genotypes. RESULTS Median DNA-TG (mDNA-TG) levels were higher in TPMT and ITPA low-activity patients as compared to wildtype patients (TPMTLA 549 vs. 364 fmol/µg DNA, p = 0.007, ITPALA 465 vs. 387 fmol/µg DNA, p = 0.04). mDNA-TG levels were positively correlated to median Ery-TGN (mEry-TGN)(rs = 0.37, p = 0.001), but plateaued at higher mEry-TGN levels. DNA-TG indices (mDNA-TG/mEry-TGN) were 42% higher in TPMTWT patients as compared to TPMTLA patients but no difference in DNA-TG indices was observed between ITPAWT and ITPALA patients (median 1.7 vs. 1.6 fmol/µg DNA/ nmol/mmol Hb, p = 0.81). DNA-TG indices increased with median Ery-MeMP (mEry-MeMP) levels (rs = 0.25, p = 0.001). CONCLUSIONS TPMT and ITPA genotypes significantly influence the metabolism of 6MP. DNA-TG may prove to be a more relevant pharmacokinetic parameter for monitoring 6MP treatment intensity than cytosolic metabolites. Prospective trials are needed to evaluate the usefulness of DNA-TGN for individual dose adjustments in childhood ALL maintenance therapy.
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Affiliation(s)
- Tina Gerbek
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark.
| | - Maria Ebbesen
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Thomas L Frandsen
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark
| | | | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark
- Institute of Clinical Medicine, The Faculty of Medicine, University of Copenhagen, Copenhagen, Denmark
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25
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Evensen NA, Madhusoodhan PP, Meyer J, Saliba J, Chowdhury A, Araten DJ, Nersting J, Bhatla T, Vincent TL, Teachey D, Hunger SP, Yang J, Schmiegelow K, Carroll WL. MSH6 haploinsufficiency at relapse contributes to the development of thiopurine resistance in pediatric B-lymphoblastic leukemia. Haematologica 2018; 103:830-839. [PMID: 29449434 PMCID: PMC5927991 DOI: 10.3324/haematol.2017.176362] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 07/02/2018] [Indexed: 01/10/2023] Open
Abstract
Survival of children with relapsed acute lymphoblastic leukemia is poor, and understanding mechanisms underlying resistance is essential to developing new therapy. Relapse-specific heterozygous deletions in MSH6, a crucial part of DNA mismatch repair, are frequently detected. Our aim was to determine whether MSH6 deletion results in a hypermutator phenotype associated with generation of secondary mutations involved in drug resistance, or if it leads to a failure to initiate apoptosis directly in response to chemotherapeutic agents. We knocked down MSH6 in mismatch repair proficient cell lines (697 and UOCB1) and showed significant increases in IC50s to 6-thioguanine and 6-mercaptopurine (697: 26- and 9-fold; UOCB1: 5- and 8-fold) in vitro, as well as increased resistance to 6-mercaptopurine treatment in vivo. No shift in IC50 was observed in deficient cells (Reh and RS4;11). 697 MSH6 knockdown resulted in increased DNA thioguanine nucleotide levels compared to non-targeted cells (3070 vs. 1722 fmol/μg DNA) with no difference observed in mismatch repair deficient cells. Loss of MSH6 did not give rise to microsatellite instability in cell lines or clinical samples, nor did it significantly increase mutation rate, but rather resulted in a defect in cell cycle arrest upon thiopurine exposure. MSH6 knockdown cells showed minimal activation of checkpoint regulator CHK1, γH2AX (DNA damage marker) and p53 levels upon treatment with thiopurines, consistent with intrinsic chemoresistance due to failure to recognize thioguanine nucleotide mismatching and initiate mismatch repair. Aberrant MSH6 adds to the list of alterations/mutations associated with acquired resistance to purine analogs emphasizing the importance of thiopurine therapy.
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Affiliation(s)
- Nikki A Evensen
- Departments of Pediatrics and Pathology, Perlmutter Cancer Center, NYU-Langone Medical Center, New York, NY, USA
| | - P Pallavi Madhusoodhan
- Departments of Pediatrics and Pathology, Perlmutter Cancer Center, NYU-Langone Medical Center, New York, NY, USA
| | - Julia Meyer
- Huntsman Cancer Institute, University of Utah Medical Center, Salt Lake City, USA
| | - Jason Saliba
- Departments of Pediatrics and Pathology, Perlmutter Cancer Center, NYU-Langone Medical Center, New York, NY, USA
| | - Ashfiyah Chowdhury
- Departments of Pediatrics and Pathology, Perlmutter Cancer Center, NYU-Langone Medical Center, New York, NY, USA
| | - David J Araten
- Department of Medicine, Perlmutter Cancer Center, NYU-Langone Medical Center, New York NY, USA
| | - Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Teena Bhatla
- Departments of Pediatrics and Pathology, Perlmutter Cancer Center, NYU-Langone Medical Center, New York, NY, USA
| | - Tiffaney L Vincent
- Department of Pediatrics and the Center for Childhood Cancer Research, Children's Hospital of Philadelphia and The Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA, USA
| | - David Teachey
- Department of Pediatrics and the Center for Childhood Cancer Research, Children's Hospital of Philadelphia and The Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA, USA
| | - Stephen P Hunger
- Department of Pediatrics and the Center for Childhood Cancer Research, Children's Hospital of Philadelphia and The Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA, USA
| | - Jun Yang
- St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - William L Carroll
- Departments of Pediatrics and Pathology, Perlmutter Cancer Center, NYU-Langone Medical Center, New York, NY, USA
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26
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Tulstrup M, Frandsen TL, Abrahamsson J, Lund B, Vettenranta K, Jonsson OG, Marquart HVH, Albertsen BK, Heyman M, Schmiegelow K. Individualized 6-mercaptopurine increments in consolidation treatment of childhood acute lymphoblastic leukemia: A NOPHO randomized controlled trial. Eur J Haematol 2017; 100:53-60. [DOI: 10.1111/ejh.12979] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Morten Tulstrup
- Department of Pediatrics and Adolescent Medicine; University Hospital Rigshospitalet; Copenhagen Denmark
| | - Thomas L. Frandsen
- Department of Pediatrics and Adolescent Medicine; University Hospital Rigshospitalet; Copenhagen Denmark
| | - Jonas Abrahamsson
- Department of Pediatrics; Institution for Clinical Sciences; Sahlgrenska Academy; University of Gothenburg; Gothenburg Sweden
| | - Bendik Lund
- Department of Pediatrics; St. Olavs Hospital; Trondheim University Hospital; Trondheim Norway
- Department of Laboratory Medicine; Faculty of Medicine and Health sciences; Children's and Women's Health; Norwegian University of Science and Technology; Trondheim Norway
| | - Kim Vettenranta
- Department of Paediatrics; University of Tampere; Tampere Finland
| | | | | | | | - Mats Heyman
- Department of Pediatrics; Astrid Lindgrens Hospital; Stockholm Sweden
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine; University Hospital Rigshospitalet; Copenhagen Denmark
- Institute of Clinical Medicine; University of Copenhagen; Copenhagen Denmark
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27
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Toksvang LN, De Pietri S, Nielsen SN, Nersting J, Albertsen BK, Wehner PS, Rosthøj S, Lähteenmäki PM, Nilsson D, Nystad TA, Grell K, Frandsen TL, Schmiegelow K. Hepatic sinusoidal obstruction syndrome during maintenance therapy of childhood acute lymphoblastic leukemia is associated with continuous asparaginase therapy and mercaptopurine metabolites. Pediatr Blood Cancer 2017; 64. [PMID: 28423235 DOI: 10.1002/pbc.26519] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 01/19/2017] [Accepted: 02/10/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND Hepatic sinusoidal obstruction syndrome (SOS) during treatment of childhood acute lymphoblastic leukemia (ALL) has mainly been associated with 6-thioguanine. The occurrence of several SOS cases after the introduction of extended pegylated asparaginase (PEG-asparaginase) therapy in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol led us to hypothesize that PEG-asparaginase, combined with other drugs, may trigger SOS during 6-thioguanine-free maintenance therapy. PROCEDURE In children with ALL treated in Denmark according to the NOPHO ALL2008 protocol, we investigated the risk of SOS during methotrexate (MTX)/6-mercaptopurine (6MP) maintenance therapy that included PEG-asparaginase until week 33 (randomized to two- vs. six-week intervals), as well as alternating high-dose MTX or vincristine/dexamethasone pulses every four weeks. RESULTS Among 130 children receiving PEG-asparaginase biweekly, 29 developed SOS (≥2 criteria: hyperbilirubinemia, hepatomegaly, ascites, weight gain ≥2.5%, unexplained thrombocytopenia <75 × 109 l-1 ) at a median of 30 days (interquartile range [IQR]: 17-66) into maintenance (cumulative incidence: 27%). SOS cases fulfilling one, two, or three Ponte di Legno criteria were classified as possible (n = 2), probable (n = 8), or verified (n = 19) SOS, respectively. Twenty-six cases (90%) occurred during PEG-asparaginase treatment, including 21 (81%) within 14 days from the last chemotherapy pulse compared with the subsequent 14 days (P = 0.0025). Cytotoxic 6MP metabolites were significantly higher on PEG-asparaginase compared to after its discontinuation. Time-dependent Cox regression analysis showed increased SOS hazard ratio (HR) for erythrocyte levels of methylated 6MP metabolites (HR: 1.09 per 1,000 nmol/mmol hemoglobin increase, 95% confidence interval: 1.05-1.14). Six-week PEG-asparaginase intervals significantly reduced SOS-specific hazards (P < 0.01). CONCLUSIONS PEG-asparaginase increases cytotoxic 6MP metabolite levels and risk of SOS, potentially interacting with other chemotherapy pulses.
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Affiliation(s)
- Linea Natalie Toksvang
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Silvia De Pietri
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Stine N Nielsen
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | | | - Peder S Wehner
- Department of Pediatric Hematology and Oncology, H. C. Andersen Children's Hospital, Odense University Hospital, Odense, Denmark
| | - Steen Rosthøj
- Department of Pediatrics, Aalborg University Hospital, Aalborg, Denmark
| | - Päivi M Lähteenmäki
- Department of Pediatric and Adolescent Medicine, Turku University Hospital, Turku, Finland
| | - Daniel Nilsson
- Department of Pediatrics, Astrid Lindgrens Hospital, Stockholm, Sweden
| | - Tove A Nystad
- Department of Pediatrics, University Hospital North Norway, Tromsø, Norway
| | - Kathrine Grell
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark.,Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Thomas L Frandsen
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark.,Institute of Clinical Medicine, The Faculty of Medicine, University of Copenhagen, Copenhagen, Denmark
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28
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DNA-thioguanine nucleotide concentration and relapse-free survival during maintenance therapy of childhood acute lymphoblastic leukaemia (NOPHO ALL2008): a prospective substudy of a phase 3 trial. Lancet Oncol 2017; 18:515-524. [PMID: 28258828 DOI: 10.1016/s1470-2045(17)30154-7] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/09/2017] [Accepted: 01/17/2017] [Indexed: 02/06/2023]
Abstract
BACKGROUND Adjustment of mercaptopurine and methotrexate maintenance therapy of acute lymphoblastic leukaemia by leucocyte count is confounded by natural variations. Cytotoxicity is primarily mediated by DNA-incorporated thioguanine nucleotides (DNA-TGN). The aim of this study was to establish whether DNA-TGN concentrations in blood leucocytes during maintenance therapy are associated with relapse-free survival. METHODS In this substudy of the NOPHO ALL2008 phase 3 trial done in 23 hospitals in seven European countries (Denmark, Estonia, Finland, Iceland, Lithuania, Norway, and Sweden), we analysed data from centralised and blinded analyses of 6-mercaptopurine and methotrexate metabolites in blood samples from patients with non-high-risk childhood acute lymphoblastic leukaemia. Eligible patients were aged 1·0-17·9 years; had been diagnosed with non-high-risk precursor B-cell or T-cell leukaemia; had been treated according to the Nordic Society of Pediatric Hematology and Oncology ALL2008 protocol; and had reached maintenance therapy in first remission. Maintenance therapy was (mercaptopurine 75 mg/m2 once per day and methotrexate 20 mg/m2 once per week, targeted to a leucocyte count of 1·5-3·0 × 109 cells per L). We measured DNA-TGN and erythrocyte concentrations of TGN nucleotides, methylated mercaptopurine metabolites, and methotrexate polyglutamates. The primary objective was the association of DNA-TGN concentrations and 6-mercaptopurine and methotrexate metabolites with relapse-free survival. The secondary endpoint was the assessment of DNA-TGN concentration and 6-mercaptopurine and methotrexate metabolites during maintenance therapy phase 2. FINDINGS Between Nov 26, 2008 and June 14, 2016, 1509 patients from the NOPHO ALL2008 study were assessed for eligibility in the DNA-TGN substudy, of which 918 (89%) of 1026 eligible patients had at least one DNA-TGN measurement and were included in the analyses. Median follow-up was 4·6 years (IQR 3·1-6·1). Relapse-free survival was significantly associated with DNA-TGN concentration (adjusted hazard ratio 0·81 per 100 fmol/μg DNA increase, 95% CI 0·67-0·98; p=0·029). In patients with at least five blood samples, erythrocyte concentrations of TGN, methylated mercaptopurine metabolites, and methotrexate polyglutamates were associated with DNA-TGN concentration (all p<0·0001). INTERPRETATION Our results suggest the need for intervention trials to identify clinically applicable strategies for individualised drug dosing to increase DNA-TGN concentration, and randomised studies to investigate whether such strategies improve cure rates compared with current dose adjustments based on white blood cell counts. FUNDING Danish Cancer Society, Childhood Cancer Foundation (Denmark), Childhood Cancer Foundation (Sweden), Nordic Cancer Union, Otto Christensen Foundation, University Hospital Rigshospitalet, and Novo Nordic Foundation.
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Schmiegelow K, Nersting J, Nielsen SN, Heyman M, Wesenberg F, Kristinsson J, Vettenranta K, Schrøeder H, Weinshilboum R, Jensen KL, Grell K, Rosthoej S. Maintenance therapy of childhood acute lymphoblastic leukemia revisited-Should drug doses be adjusted by white blood cell, neutrophil, or lymphocyte counts? Pediatr Blood Cancer 2016; 63:2104-2111. [PMID: 27447547 DOI: 10.1002/pbc.26139] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 06/16/2016] [Accepted: 06/22/2016] [Indexed: 01/01/2023]
Abstract
BACKGROUND 6-Mercaptopurine (6MP) and methotrexate (MTX) based maintenance therapy is a critical phase of childhood acute lymphoblastic leukemia treatment. Wide interindividual variations in drug disposition warrant frequent doses adjustments, but there is a lack of international consensus on dose adjustment guidelines. PROCEDURE To identify relapse predictors, we collected 28,255 data sets on drug doses and blood counts (median: 47/patient) and analyzed erythrocyte (Ery) levels of cytotoxic 6MP/MTX metabolites in 9,182 blood samples (median: 14 samples/patient) from 532 children on MTX/6MP maintenance therapy targeted to a white blood cell count (WBC) of 1.5-3.5 × 109 /l. RESULTS After a median follow-up of 13.8 years for patients in remission, stepwise Cox regression analysis did not find age, average doses of 6MP and MTX, hemoglobin, absolute lymphocyte counts, thrombocyte counts, or Ery levels of 6-thioguanine nucleotides or MTX (including its polyglutamates) to be significant relapse predictors. The parameters significantly associated with risk of relapse (N = 83) were male sex (hazard ratio [HR] 2.0 [1.3-3.1], P = 0.003), WBC at diagnosis (HR = 1.04 per 10 × 109 /l rise [1.00-1.09], P = 0.048), the absolute neutrophil count (ANC; HR = 1.7 per 109 /l rise [1.3-2.4], P = 0.0007), and Ery thiopurine methyltransferase activity (HR = 2.7 per IU/ml rise [1.1-6.7], P = 0.03). WBC was significantly related to ANC (Spearman correlation coefficient, rs = 0.77; P < 0.001), and only a borderline significant risk factor for relapse (HR = 1.28 [95% CI: 1.00-1.64], P = 0.046) when ANC was excluded from the Cox model. CONCLUSIONS This study indicates that a low neutrophil count is likely to be the best hematological target for dose adjustments of maintenance therapy.
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Affiliation(s)
- Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark. .,Faculty of Medicine, Institute of Clinical Medicine, University of Copenhagen, Denmark.
| | - Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Stine Nygaard Nielsen
- Department of Pediatrics and Adolescent Medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Mats Heyman
- Astrid Lindgrens Barnsjukhus, Stockholm, Sweden
| | - Finn Wesenberg
- Department of Pediatric Oncology, The University Hospital Rikshospitalet, Oslo, Norway
| | - Jon Kristinsson
- Department of Pediatric Oncology, The National Hospital, Reykjavik, Iceland
| | - Kim Vettenranta
- Department of Pediatric Oncology, The University Hospital, Helsinki, Finland
| | - Henrik Schrøeder
- Department of Pediatric Oncology, Århus University Hospital, Denmark
| | | | - Katrine Lykke Jensen
- Section of Biostatistics, Department of Public Health, The University of Copenhagen, Copenhagen, Denmark
| | - Kathrine Grell
- Section of Biostatistics, Department of Public Health, The University of Copenhagen, Copenhagen, Denmark
| | - Susanne Rosthoej
- Section of Biostatistics, Department of Public Health, The University of Copenhagen, Copenhagen, Denmark
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Shipkova M, Valbuena H. Liquid chromatography tandem mass spectrometry for therapeutic drug monitoring of immunosuppressive drugs: Achievements, lessons and open issues. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2016.01.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Measures of 6-mercaptopurine and methotrexate maintenance therapy intensity in childhood acute lymphoblastic leukemia. Cancer Chemother Pharmacol 2016; 78:983-994. [PMID: 27600880 DOI: 10.1007/s00280-016-3151-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 08/26/2016] [Indexed: 02/07/2023]
Abstract
PURPOSE Normal white blood cell counts (WBC) are unknown in children with acute lymphoblastic leukemia (ALL). Accordingly, 6-mercaptopurine (6MP) and methotrexate (MTX) maintenance therapy is adjusted by a common WBC target of 1.5-3.0 × 109/L. Consequently, the absolute degree of myelosuppression is unknown for the individual child and we wanted to evaluate this. METHODS A median of 22 (range 8-27) 6MP/MTX metabolite samples and 100 (range 25-130) blood counts during therapy and 10 (range 2-15) off therapy were collected in 50 children with ALL. Differences between off-therapy and on-therapy WBCs [including absolute neutrophil (ANC) and lymphocyte counts (ALC)] were used to retrospectively approximate the absolute myelosuppression (="delta-") and association with age, sex and 6MP/MTX doses explored. We applied linear mixed models to estimate on-therapy counts by 6MP/MTX metabolites: DNA-incorporated thioguanine nucleotides (DNA-TGN), erythrocyte thioguanine nucleotides (ery-TGN), erythrocyte-methylated 6MP metabolites (ery-MeMP) and erythrocyte MTX polyglutamates with 2-6 glutamate residues (ery-MTXpg2-6). RESULTS On-therapy WBC was correlated with ANC and ALC (r s = 0.84 and r s = 0.33, p values <0.001), whereas ANC was weakly correlated with ALC (r s = -0.11, p < 0.001), and neither significantly correlated with age. Off-therapy ALC, but not ANC, was strongly correlated with age (r s = -0.68 and -0.18, p < 0.001 and p = 0.22). Delta-ALC decreased with increasing age (r s = -0.69, p < 0.001). Incorporation of DNA-TGN was positively associated with ery-TGN (p < 0.001), ery-MeMP (p < 0.001) and ery-MTXpg2-6 (p = 0.047). On-therapy ALC decreased with increasing DNA-TGN level (p < 0.001, model adjusted for off-therapy ALC), whereas on-therapy ANC could not be modeled reliably. CONCLUSION Measurements of 6MP/MTX metabolites could supplement blood counts in assessing therapy intensity, but require prospective validation.
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Shipkova M, Svinarov D. LC–MS/MS as a tool for TDM services: Where are we? Clin Biochem 2016; 49:1009-23. [DOI: 10.1016/j.clinbiochem.2016.05.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 04/23/2016] [Accepted: 05/01/2016] [Indexed: 12/23/2022]
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Coulthard SA, Berry P, McGarrity S, Ansari A, Redfern CPF. Liquid chromatography-mass spectrometry for measuring deoxythioguanosine in DNA from thiopurine-treated patients. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1028:175-180. [PMID: 27362994 PMCID: PMC4955110 DOI: 10.1016/j.jchromb.2016.06.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/26/2016] [Accepted: 06/12/2016] [Indexed: 01/14/2023]
Abstract
Thiopurines are effective immunosuppressant drugs. Monitoring of thiopurines is needed for research and clinical use. A sensitive assay of DNA-incorporated deoxythioguanosine is described. This method assays thiopurine nucleotides in DNA from nucleated blood cells.
Adverse reactions and non-response are common in patients treated with thiopurine drugs. Current monitoring of drug metabolite levels for guiding treatment are limited to analysis of thioguanine nucleotides (TGNs) in erythrocytes after chemical derivatisation. Erythrocytes are not the target tissue and TGN levels show poor correlations with clinical response. We have developed a sensitive assay to quantify deoxythioguanosine (dTG) without derivatisation in the DNA of nucleated blood cells. Using liquid chromatography and detection by tandem mass spectrometry, an intra- and inter-assay variability below 7.8% and 17.0% respectively were achieved. The assay had a detection limit of 0.0003125 ng (1.1 femtomoles) dTG and was quantified in DNA samples relative to endogenous deoxyadenosine (dA) in a small group of 20 patients with inflammatory bowel disease, all of whom had been established on azathioprine (AZA) therapy for more than 25 weeks. These patients had dTG levels of 20–1360 mol dTG/106 mol dA; three patients who had not started therapy had no detectable dTG. This method, comparable to previous methods in sensitivity, enables the direct detection of a cytotoxic thiopurine metabolite without derivatisation in an easily obtainable, stable sample and will facilitate a better understanding of the mechanisms of action of these inexpensive yet effective drugs.
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Affiliation(s)
- Sally A Coulthard
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
| | - Phil Berry
- Northern Institute of Cancer Research, Newcastle University, Newcastle upon Tyne, UK
| | - Sarah McGarrity
- Northern Institute of Cancer Research, Newcastle University, Newcastle upon Tyne, UK
| | - Azhar Ansari
- Gastroenterology Dept., East Surrey Hospital, Redhill, East Surrey, UK
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Mirmomtaz E, Zirakbash A, Ensafi AA. An electrochemical DNA sensor for determination of 6-thioguanine using adsorptive stripping voltammetry at HMDE: An anticancer drug DNA interaction study. RUSS J ELECTROCHEM+ 2016. [DOI: 10.1134/s1023193516040078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Smarzewska S, Pokora J, Leniart A, Festinger N, Ciesielski W. Carbon Paste Electrodes Modified with Graphene Oxides - Comparative Electrochemical Studies of Thioguanine. ELECTROANAL 2016. [DOI: 10.1002/elan.201501101] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sylwia Smarzewska
- Department of Inorganic and Analytical Chemistry; University of Lodz; Tamka 12 91-403 Lodz Poland
| | - Joanna Pokora
- Department of Inorganic and Analytical Chemistry; University of Lodz; Tamka 12 91-403 Lodz Poland
| | - Andrzej Leniart
- Department of Inorganic and Analytical Chemistry; University of Lodz; Tamka 12 91-403 Lodz Poland
| | - Natalia Festinger
- Department of Inorganic and Analytical Chemistry; University of Lodz; Tamka 12 91-403 Lodz Poland
| | - Witold Ciesielski
- Department of Inorganic and Analytical Chemistry; University of Lodz; Tamka 12 91-403 Lodz Poland
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Moriyama T, Nishii R, Perez-Andreu V, Yang W, Klussmann FA, Zhao X, Lin TN, Hoshitsuki K, Nersting J, Kihira K, Hofmann U, Komada Y, Kato M, McCorkle R, Li L, Koh K, Najera CR, Kham SKY, Isobe T, Chen Z, Chiew EKH, Bhojwani D, Jeffries C, Lu Y, Schwab M, Inaba H, Pui CH, Relling MV, Manabe A, Hori H, Schmiegelow K, Yeoh AEJ, Evans WE, Yang JJ. NUDT15 polymorphisms alter thiopurine metabolism and hematopoietic toxicity. Nat Genet 2016; 48:367-73. [PMID: 26878724 DOI: 10.1038/ng.3508] [Citation(s) in RCA: 340] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/15/2016] [Indexed: 12/14/2022]
Abstract
Widely used as anticancer and immunosuppressive agents, thiopurines have narrow therapeutic indices owing to frequent toxicities, partly explained by TPMT genetic polymorphisms. Recent studies identified germline NUDT15 variation as another critical determinant of thiopurine intolerance, but the underlying molecular mechanisms and the clinical implications of this pharmacogenetic association remain unknown. In 270 children enrolled in clinical trials for acute lymphoblastic leukemia in Guatemala, Singapore and Japan, we identified four NUDT15 coding variants (p.Arg139Cys, p.Arg139His, p.Val18Ile and p.Val18_Val19insGlyVal) that resulted in 74.4-100% loss of nucleotide diphosphatase activity. Loss-of-function NUDT15 diplotypes were consistently associated with thiopurine intolerance across the three cohorts (P = 0.021, 2.1 × 10(-5) and 0.0054, respectively; meta-analysis P = 4.45 × 10(-8), allelic effect size = -11.5). Mechanistically, NUDT15 inactivated thiopurine metabolites and decreased thiopurine cytotoxicity in vitro, and patients with defective NUDT15 alleles showed excessive levels of thiopurine active metabolites and toxicity. Taken together, these results indicate that a comprehensive pharmacogenetic model integrating NUDT15 variants may inform personalized thiopurine therapy.
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Affiliation(s)
- Takaya Moriyama
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,Department of Pediatrics, Mie University Graduate School of Medicine, Mie, Japan
| | - Rina Nishii
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,Department of Pediatrics and Developmental Biology, Tokyo Medical and Dental University Graduate School of Medicine, Tokyo, Japan
| | - Virginia Perez-Andreu
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Wenjian Yang
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Federico Antillon Klussmann
- Unidad Nacional de Oncología Pediátrica, Guatemala City, Guatemala.,Francisco Marroquin Medical School, Guatemala City, Guatemala
| | - Xujie Zhao
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Ting-Nien Lin
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Keito Hoshitsuki
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Jacob Nersting
- Department of Paediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Kentaro Kihira
- Department of Pediatrics, Mie University Graduate School of Medicine, Mie, Japan
| | - Ute Hofmann
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany.,Department of Clinical Pharmacology, University Hospital Tübingen, Tübingen, Germany
| | - Yoshihiro Komada
- Department of Pediatrics, Mie University Graduate School of Medicine, Mie, Japan
| | - Motohiro Kato
- Department of Pediatric Hematology and Oncology Research, National Center for Child Health and Development, Tokyo, Japan
| | - Robert McCorkle
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Lie Li
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Katsuyoshi Koh
- Department of Hematology/Oncology, Saitama Children's Medical Center, Saitama, Japan
| | | | - Shirley Kow-Yin Kham
- National University Cancer Institute, National University Health System, Singapore
| | - Tomoya Isobe
- Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Zhiwei Chen
- National University Cancer Institute, National University Health System, Singapore
| | | | - Deepa Bhojwani
- Department of Pediatrics, Children's Hospital of Los Angeles, Los Angeles, California, USA
| | - Cynthia Jeffries
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Yan Lu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany.,Department of Clinical Pharmacology, University Hospital Tübingen, Tübingen, Germany.,German Cancer Consortium, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Department of Pharmacy and Biochemistry, University of Tübingen, Tübingen, Germany
| | - Hiroto Inaba
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Ching-Hon Pui
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Mary V Relling
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Atsushi Manabe
- Department of Pediatrics, St. Luke's International Hospital, Tokyo, Japan
| | - Hiroki Hori
- Department of Pediatrics, Mie University Graduate School of Medicine, Mie, Japan
| | - Kjeld Schmiegelow
- Department of Paediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark.,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Allen E J Yeoh
- National University Cancer Institute, National University Health System, Singapore.,Viva University Children's Cancer Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - William E Evans
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Jun J Yang
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
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Cytosine derivatized bis(2,2′-bithienyl)methane molecularly imprinted polymer for selective recognition of 6-thioguanine, an antitumor drug. Biosens Bioelectron 2015; 70:153-60. [DOI: 10.1016/j.bios.2015.03.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 02/11/2015] [Accepted: 03/02/2015] [Indexed: 12/11/2022]
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Mercaptopurine metabolite levels are predictors of bone marrow toxicity following high-dose methotrexate therapy of childhood acute lymphoblastic leukaemia. Cancer Chemother Pharmacol 2015; 75:1089-93. [PMID: 25788208 DOI: 10.1007/s00280-015-2717-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 02/25/2015] [Indexed: 10/23/2022]
Abstract
High-dose methotrexate (HD-MTX) courses with concurrent oral low-dose MTX/6-mercaptopurine (6MP) for childhood acute lymphoblastic leukaemia (ALL) are often followed by neutro- and thrombocytopenia necessitating treatment interruptions. Plasma MTX during HD-MTX therapy guides folinic acid rescue to prevent toxicities, but myelosuppression can also be prevented by pre-HD-MTX 6MP dose reductions. Accordingly, we monitored pre-HD-MTX erythrocyte levels of methylated 6MP metabolites (Ery-MeMP) and of thioguanine nucleotides (Ery-6TGN) as well as DNA-incorporated thioguanine nucleotides (DNA-TGN) in circulating leucocytes to identify patients at highest risk of post-HD-MTX myelosuppression. In multiple linear regression analyses of neutrophil and thrombocyte nadir values (adjusted for gender, age, risk group and 6MP dose) after 48 HD-MTX courses in 17 childhood ALL patients on MTX/6MP maintenance therapy, the pre-HD-MTX DNA-TGN levels in neutrophils (P < 0.0001), Ery-MeMP (P < 0.0001) and Ery-6TGN (P = 0.01) levels were significant predictors of post-HD-MTX neutrophil nadirs, whereas Ery-MeMP (P < 0.0001) was the only predictor of post-HD-MTX thrombocyte nadir. In conclusion, pre-HD-MTX 6MP metabolite levels may be applicable for 6MP dose adjustments to prevent HD-MTX-induced myelosuppression.
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Eksin E, Congur G, Mese F, Erdem A. Electrochemical monitoring of surface confined interaction between 6-Thioguanine and DNA by using single-use graphite electrode. J Electroanal Chem (Lausanne) 2014. [DOI: 10.1016/j.jelechem.2014.08.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Abstract
The antileukemic mechanisms of 6-mercaptopurine (6MP) and methotrexate (MTX) maintenance therapy are poorly understood, but the benefits of several years of myelosuppressive maintenance therapy for acute lymphoblastic leukemia are well proven. Currently, there is no international consensus on drug dosing. Because of significant interindividual and intraindividual variations in drug disposition and pharmacodynamics, vigorous dose adjustments are needed to obtain a target degree of myelosuppression. As the normal white blood cell counts vary by patients' ages and ethnicity, and also within age groups, identical white blood cell levels for 2 patients may not reflect the same treatment intensity. Measurements of intracellular levels of cytotoxic metabolites of 6MP and MTX can identify nonadherent patients, but therapeutic target levels remains to be established. A rise in serum aminotransferase levels during maintenance therapy is common and often related to high levels of methylated 6MP metabolites. However, except for episodes of hypoglycemia, serious liver dysfunction is rare, the risk of permanent liver damage is low, and aminotransferase levels usually normalize within a few weeks after discontinuation of therapy. 6MP and MTX dose increments should lead to either leukopenia or a rise in aminotransferases, and if neither is experienced, poor treatment adherence should be considered. The many genetic polymorphisms that determine 6MP and MTX disposition, efficacy, and toxicity have precluded implementation of pharmacogenomics into treatment, the sole exception being dramatic 6MP dose reductions in patients who are homozygous deficient for thiopurine methyltransferase, the enzyme that methylates 6MP and several of its metabolites. In conclusion, maintenance therapy is as important as the more intensive and toxic earlier treatment phases, and often more challenging. Ongoing research address the applicability of drug metabolite measurements for dose adjustments, extensive host genome profiling to understand diversity in treatment efficacy and toxicity, and alternative thiopurine dosing regimens to improve therapy for the individual patient.
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Analysis of thiopurines using aqueous normal phase chromatography. J Pharm Biomed Anal 2014; 95:102-6. [PMID: 24657678 DOI: 10.1016/j.jpba.2014.02.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 02/22/2014] [Accepted: 02/25/2014] [Indexed: 11/22/2022]
Abstract
The chromatography of several thiopurines is investigated using aqueous normal phase (ANP) conditions in conjunction with a silica hydride-based column. Both isocratic and gradient elution modes are tested. Detection of higher concentration samples is done by UV to demonstrate feasibility in this format while lower concentration samples utilize mass spectrometry (MS). Repeatability of successive runs is also tested with particular attention to gradient methods where the equilibration time of the stationary phase can be evaluated.
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García-Gómez D, Rodríguez-Gonzalo E, Carabias-Martínez R. Stationary phases for separation of nucleosides and nucleotides by hydrophilic interaction liquid chromatography. Trends Analyt Chem 2013. [DOI: 10.1016/j.trac.2013.02.011] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Ebbesen MS, Nersting J, Jacobsen JH, Frandsen TL, Vettenranta K, Abramsson J, Wesenberg F, Schmiegelow K. Incorporation of 6-thioguanine nucleotides into DNA during maintenance therapy of childhood acute lymphoblastic leukemia-the influence of thiopurine methyltransferase genotypes. J Clin Pharmacol 2013; 53:670-4. [PMID: 23585236 DOI: 10.1002/jcph.81] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 03/07/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Maria S Ebbesen
- Department of Pediatrics and Adolescent Medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark
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Du J, Wang Y, Zhang W. Label‐Free, Non‐Derivatization CRET Detection Platform for 6‐Mercaptopurine Based on the Distance‐Dependent Optical Properties of Gold Nanoparticles. Chemistry 2012; 18:8540-6. [DOI: 10.1002/chem.201200013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Revised: 03/25/2012] [Indexed: 12/19/2022]
Affiliation(s)
- Jianxiu Du
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062 (P. R. China), Fax: (+86) 29‐8153‐0727
| | - Yadi Wang
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062 (P. R. China), Fax: (+86) 29‐8153‐0727
| | - Weimin Zhang
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062 (P. R. China), Fax: (+86) 29‐8153‐0727
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