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Guo HL, Zhao YT, Wang WJ, Dong N, Hu YH, Zhang YY, Chen F, Zhou L, Li T. Optimizing thiopurine therapy in children with acute lymphoblastic leukemia: A promising “MINT” sequencing strategy and therapeutic “DNA-TG” monitoring. Front Pharmacol 2022; 13:941182. [PMID: 36238550 PMCID: PMC9552076 DOI: 10.3389/fphar.2022.941182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/02/2022] [Indexed: 11/13/2022] Open
Abstract
Thiopurines, including thioguanine (TG), 6-mercaptopurine (6-MP), and azathioprine (AZA), are extensively used in clinical practice in children with acute lymphoblastic leukemia (ALL) and inflammatory bowel diseases. However, the common adverse effects caused by myelosuppression and hepatotoxicity limit their application. Metabolizing enzymes such as thiopurine S-methyltransferase (TPMT), nudix hydrolase 15 (NUDT15), inosine triphosphate pyrophosphohydrolase (ITPA), and drug transporters like multidrug resistance-associated protein 4 (MRP4) have been reported to mediate the metabolism and transportation of thiopurine drugs. Hence, the single nucleotide polymorphisms (SNPs) in those genes could theoretically affect the pharmacokinetics and pharmacological effects of these drugs, and might also become one of the determinants of clinical efficacy and adverse effects. Moreover, long-term clinical practices have confirmed that thiopurine-related adverse reactions are associated with the systemic concentrations of their active metabolites. In this review, we mainly summarized the pharmacogenetic studies of thiopurine drugs. We also evaluated the therapeutic drug monitoring (TDM) research studies and focused on those active metabolites, hoping to continuously improve monitoring strategies for thiopurine therapy to maximize therapeutic efficacy and minimize the adverse effects or toxicity. We proposed that tailoring thiopurine dosing based on MRP4, ITPA, NUDT15, and TMPT genotypes, defined as “MINT” panel sequencing strategy, might contribute toward improving the efficacy and safety of thiopurines. Moreover, the DNA-incorporated thioguanine nucleotide (DNA-TG) metabolite level was more suitable for red cell 6-thioguanine nucleotide (6-TGNs) monitoring, which can better predict the efficacy and safety of thiopurines. Integrating the panel “MINT” sequencing strategy with therapeutic “DNA-TG” monitoring would offer a new insight into the precision thiopurine therapy for pediatric acute lymphoblastic leukemia patients.
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Affiliation(s)
- Hong-Li Guo
- Pharmaceutical Sciences Research Center, Department of Pharmacy, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Yue-Tao Zhao
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
- Visiting Graduate Student from School of Basic Medicine and Clinical Pharmacy, Pharmaceutical University, Nanjing, China
| | - Wei-Jun Wang
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
- Visiting Graduate Student from School of Basic Medicine and Clinical Pharmacy, Pharmaceutical University, Nanjing, China
| | - Na Dong
- Institute of Pharmaceutical Science, China Pharmaceutical University, Nanjing, China
- School of Institute of Pharmaceutical Science, Pharmaceutical University, Nanjing, China
| | - Ya-Hui Hu
- Pharmaceutical Sciences Research Center, Department of Pharmacy, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Yuan-Yuan Zhang
- Pharmaceutical Sciences Research Center, Department of Pharmacy, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Feng Chen
- Pharmaceutical Sciences Research Center, Department of Pharmacy, Children’s Hospital of Nanjing Medical University, Nanjing, China
- *Correspondence: Feng Chen, ; Li Zhou, ; Tao Li,
| | - Li Zhou
- Hematology and Oncology Department, Children’s Hospital of Nanjing Medical University, Nanjing, China
- *Correspondence: Feng Chen, ; Li Zhou, ; Tao Li,
| | - Tao Li
- Department of Solid Oncology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- *Correspondence: Feng Chen, ; Li Zhou, ; Tao Li,
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Lee Y, Jang EJ, Yoon HY, Yee J, Gwak HS. Effect of ITPA Polymorphism on Adverse Drug Reactions of 6-Mercaptopurine in Pediatric Patients with Acute Lymphoblastic Leukemia: A Systematic Review and Meta-Analysis. Pharmaceuticals (Basel) 2022; 15:ph15040416. [PMID: 35455413 PMCID: PMC9027773 DOI: 10.3390/ph15040416] [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: 02/28/2022] [Revised: 03/23/2022] [Accepted: 03/28/2022] [Indexed: 02/06/2023] Open
Abstract
6-Mercaptopurine (6-MP) is a cornerstone of the maintenance regimen for pediatric acute lymphoblastic leukemia (ALL). Inosine triphosphate pyrophosphatase (ITPA) is considered a candidate pharmacogenetic marker that may affect metabolism and 6-MP-induced toxicities; however, the findings are inconsistent. Therefore, we attempted to evaluate the effect of ITPA 94C>A polymorphism on 6-MP-induced hematological toxicity and hepatotoxicity through a systematic review and meta-analysis. A literature search for qualifying studies was conducted using the PubMed, Web of Science, and Embase databases until October 2021. Overall, 10 eligible studies with 1072 pediatric ALL patients were included in this meta-analysis. The results indicated that ITPA 94C>A was significantly associated with 6-MP-induced neutropenia (OR 2.38, 95% CI: 1.56−3.62; p = 0.005) and hepatotoxicity (OR 1.98, 95% CI: 1.32−2.95; p = 0.0009); however, no significant association was found between the ITPA 94C>A variant and 6-MP-induced leukopenia (OR 1.75, 95% CI: 0.74−4.12; p = 0.20). This meta-analysis demonstrated that ITPA 94C>A polymorphism could affect 6-MP-induced toxicities. Our findings suggested that ITPA genotyping might help predict 6-MP-induced myelosuppression and hepatotoxicity.
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Affiliation(s)
- Yeonhong Lee
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Korea; (Y.L.); (E.J.J.); (H.-Y.Y.); (J.Y.)
- Department of Pharmacy, National Cancer Center, Goyang-si 10408, Korea
| | - Eun Jeong Jang
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Korea; (Y.L.); (E.J.J.); (H.-Y.Y.); (J.Y.)
| | - Ha-Young Yoon
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Korea; (Y.L.); (E.J.J.); (H.-Y.Y.); (J.Y.)
| | - Jeong Yee
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Korea; (Y.L.); (E.J.J.); (H.-Y.Y.); (J.Y.)
| | - Hye-Sun Gwak
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Korea; (Y.L.); (E.J.J.); (H.-Y.Y.); (J.Y.)
- Correspondence: ; Tel.: +82-2-3277-4376; Fax: +82-2-3277-3051
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Boonyawat B, Monsereenusorn C, Photia A, Lertvivatpong N, Kaewchaivijit V, Jindatanmanusan P, Rujkijyanont P. ITPA:c.94C>A and NUDT15:c.415C>T Polymorphisms and Their Relation to Mercaptopurine-Related Myelotoxicity in Childhood Leukemia in Thailand. APPLICATION OF CLINICAL GENETICS 2021; 14:341-351. [PMID: 34349542 PMCID: PMC8326781 DOI: 10.2147/tacg.s318912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/19/2021] [Indexed: 11/30/2022]
Abstract
Background Mercaptopurine is a key agent in childhood leukemia treatment. Genetic polymorphism in the genes involving thiopurine metabolisms is related to 6-MP related toxicity. Objective This study aimed to determine the prevalence of ITPA:c.94C>A and NUDT15:c.415C>T polymorphisms among Thai children diagnosed with leukemia and their association with mercaptopurine-related myelotoxicity. Methods Patients and survivors with a diagnosis of leukemia treated with mercaptopurine-containing chemotherapy regimens were enrolled. Clinical data and laboratory parameters during treatment as well as ITPA:c.94C>A and NUDT15:c.415C>T genotypes were analyzed. Results In all, 99 patients with acute leukemia or survivors were enrolled in the study. The prevalences of ITPA:c.94C>A, NUDT15:c.415C>T, and co-occurrence of ITPA:c.94C>A and NUDT15:c.415C>T polymorphisms were 34, 17, and 4%, respectively. Numbers of absolute neutrophil count (ANC) and platelet count significantly decreased among patients carrying NUDT15:c.415C>T compared with NUDT15 wild type patients with p-values<0.001 and 0.019, respectively. The differences were not observed among patients carrying ITPA:c.94C>A compared with ITPA wild type patients. According to multivariate GEE, NUDT15:c.415C>T and co-occurrence of ITPA:c.94C>A and NUDT15:c.415C>T had a significant negative effect on ANC during treatment (coefficient: −463.81; CI: −778.53, −149.09; p-value=0.004 and coefficient: −527.56; CI: −1045.65, −9.48; p-value=0.046). No significant effect of ITPA:c.94C>A on ANC during treatment was observed. Conclusion ITPA:c.94C>A and NUDT15:c.415C>T polymorphisms are common among Thai children with leukemia. A strong association with mercaptopurine-related myelotoxicity was observed among patients carrying either NUDT15:c.415C>T alone or combined with ITPA:c.94C>A.
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Affiliation(s)
- Boonchai Boonyawat
- Division of Medical Genetics, Department of Pediatrics, Phramongkutklao College of Medicine and Phramongkutklao Hospital, Bangkok, Thailand
| | - Chalinee Monsereenusorn
- Division of Hematology-Oncology, Department of Pediatrics, Phramongkutklao College of Medicine and Phramongkutklao Hospital, Bangkok, Thailand
| | - Apichat Photia
- Division of Hematology-Oncology, Department of Pediatrics, Phramongkutklao College of Medicine and Phramongkutklao Hospital, Bangkok, Thailand
| | - Nawachai Lertvivatpong
- Division of Hematology-Oncology, Department of Pediatrics, Phramongkutklao College of Medicine and Phramongkutklao Hospital, Bangkok, Thailand
| | - Varissara Kaewchaivijit
- Department of Pediatrics, Phramongkutklao College of Medicine and Phramongkutklao Hospital, Bangkok, Thailand
| | - Punyanuch Jindatanmanusan
- Division of Hematology-Oncology, Department of Pediatrics, Phramongkutklao College of Medicine and Phramongkutklao Hospital, Bangkok, Thailand
| | - Piya Rujkijyanont
- Division of Hematology-Oncology, Department of Pediatrics, Phramongkutklao College of Medicine and Phramongkutklao Hospital, Bangkok, Thailand
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Singh A, Gangadharan H, Gupta V, Patro PS, Misra R, Aggarwal A. Polymorphism of genes involved in methotrexate pathway: Predictors of response to methotrexate therapy in Indian rheumatoid arthritis patients. Int J Rheum Dis 2021; 24:654-662. [PMID: 33780152 DOI: 10.1111/1756-185x.14100] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 02/12/2021] [Accepted: 03/06/2021] [Indexed: 11/28/2022]
Abstract
INTRODUCTION The adenosine pathway is one of the ways through which methotrexate (MTX) ameliorates inflammation. We therefore explored an association of polymorphism of genes involved in adenosine and MTX metabolic pathways with response to MTX. METHODS Association of polymorphism in 7 genes (rs2236225 [MTHFD1 1958G>A], rs17602729 [AMPD1 G>A], rs1127354 [ITPA C>A], rs1431131 [TGFBR2 A>T], rs2372536 [ATIC C>G], rs11188513 [ENTPD1 C>T] and rs5751876 [ADORA2A T>C]) with efficacy of MTX was studied in Indian rheumatoid arthritis (RA) patients. The patients, classified by European League Against Rheumatology (EULAR)/American College of Rheumatology (ACR) 2010 criteria, were DMARD (disease-modifying antirheumatic drug)-naïve, with Disease Activity Score (DAS28) >3.2. After 4 months of MTX monotherapy, patients were classified as responders (R) or non-responders (NR) based on EULAR response criteria. Genotyping was done by TaqMan 5' nuclease assay and association of gene polymorphisms with response to MTX was determined by Chi-squared test. RESULTS Two hundred and twenty-six patients (86% female, median age 40 [interquartile range, IQR = 17.25] years), with disease duration of 24 (IQR = 38.25) months and DAS28-C-reactive protein score of 4.61 (IQR = 1.34) were enrolled. After therapy, 186 patients were classified as R and 40 as NR. GG genotype of ATIC (P = .01, odds ratio [OR] 2.56, 95% CI, 1.04-6.30) and CC genotype of ITPA (P = .009, OR 1.34, 95% CI 1.02-1.76) genes were found to be associated with the response. On binary logistic regression analysis, GG genotype of ATIC and CC of ITPA genes were independent predictors of the response. CONCLUSION Polymorphisms of ATIC and ITPA genes alone or with clinical variables were associated with response to MTX therapy in Indian RA patients.
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Affiliation(s)
- Ankita Singh
- Department of Clinical Immunology & Rheumatology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Harikrishnan Gangadharan
- Department of Clinical Immunology & Rheumatology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Vikas Gupta
- Department of Clinical Immunology & Rheumatology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Pradeepta S Patro
- Department of Clinical Immunology & Rheumatology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Ramnath Misra
- Department of Clinical Immunology & Rheumatology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Amita Aggarwal
- Department of Clinical Immunology & Rheumatology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
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Saiz-Rodríguez M, Ochoa D, Belmonte C, Román M, Martínez-Ingelmo C, Ortega-Ruíz L, Sarmiento-Iglesias C, Herrador C, Abad-Santos F. Influence of thiopurine S-methyltransferase polymorphisms in mercaptopurine pharmacokinetics in healthy volunteers. Basic Clin Pharmacol Toxicol 2018; 124:449-455. [PMID: 30346660 DOI: 10.1111/bcpt.13153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 10/14/2018] [Indexed: 12/29/2022]
Abstract
Mercaptopurine is a drug commonly used in the treatment of different types of cancer, especially acute lymphoblastic leukaemia, and autoimmune diseases such as ulcerative colitis or Crohn's disease and in patients receiving organ transplants. It is metabolized by three cytosolic enzymes. One of them, thiopurine S-methyltransferase (TPMT), is responsible for catalysing the methylation reaction of mercaptopurine to 6-methylmercaptopurine, thus inactivating the drug. Individuals with TPMT loss-of-function alleles (*2, *3A, *3B or *3C) can be extremely sensitive to the effect of mercaptopurine, since it can be accumulated, therefore producing haematological toxicity. The objective of this study was to evaluate the role of TPMT polymorphisms on the pharmacokinetics of mercaptopurine. For that purpose, we used collected pharmacokinetic data from 48 healthy volunteers (all males) who received a single oral dose of mercaptopurine 50 mg in two bioequivalence studies. The volunteers were subsequently genotyped for TPMT *2, *3A, *3B and *3C alleles by real-time PCR. There were four carriers (8.3%) of TPMT*2 and TPMT*3A alleles. Mercaptopurine elimination was affected by TPMT loss-of-function polymorphisms, since heterozygous subjects show 18% higher half-life compared to wild-type individuals. This fact is consistent with the expected since the presence of loss-of-function alleles decreases TPMT enzymatic activity and, thus, affects mercaptopurine elimination. Moreover, mercaptopurine pharmacokinetic parameters were different among races, since Latins showed higher plasma concentrations and lower clearance compared to Caucasians. This fact might be due to a different distribution of polymorphisms in genes, other than TPMT, that also influence the pharmacokinetics of mercaptopurine.
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Affiliation(s)
- Miriam Saiz-Rodríguez
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain
| | - Dolores Ochoa
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain.,UICEC Hospital Universitario de La Princesa, Plataforma SCReN (Spanish Clinical Research Network), Instituto de Investigación Sanitaria La Princesa (IP), Madrid, Spain
| | - Carmen Belmonte
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain.,UICEC Hospital Universitario de La Princesa, Plataforma SCReN (Spanish Clinical Research Network), Instituto de Investigación Sanitaria La Princesa (IP), Madrid, Spain
| | - Manuel Román
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain.,UICEC Hospital Universitario de La Princesa, Plataforma SCReN (Spanish Clinical Research Network), Instituto de Investigación Sanitaria La Princesa (IP), Madrid, Spain
| | - Cristina Martínez-Ingelmo
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain
| | - Lucía Ortega-Ruíz
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain
| | - Carmen Sarmiento-Iglesias
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain
| | - Coral Herrador
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain
| | - Francisco Abad-Santos
- Clinical Pharmacology Department, Instituto Teófilo Hernando, Instituto de Investigación Sanitaria La Princesa (IP), Universidad Autónoma de Madrid (UAM), Hospital Universitario de La Princesa, Madrid, Spain.,UICEC Hospital Universitario de La Princesa, Plataforma SCReN (Spanish Clinical Research Network), Instituto de Investigación Sanitaria La Princesa (IP), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
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Cargnin S, Genazzani AA, Canonico PL, Terrazzino S. Diagnostic accuracy of NUDT15 gene variants for thiopurine-induced leukopenia: a systematic review and meta-analysis. Pharmacol Res 2018; 135:102-111. [DOI: 10.1016/j.phrs.2018.07.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/19/2018] [Accepted: 07/19/2018] [Indexed: 02/07/2023]
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Tsesmetzis N, Paulin CBJ, Rudd SG, Herold N. Nucleobase and Nucleoside Analogues: Resistance and Re-Sensitisation at the Level of Pharmacokinetics, Pharmacodynamics and Metabolism. Cancers (Basel) 2018; 10:cancers10070240. [PMID: 30041457 PMCID: PMC6071274 DOI: 10.3390/cancers10070240] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 02/07/2023] Open
Abstract
Antimetabolites, in particular nucleobase and nucleoside analogues, are cytotoxic drugs that, starting from the small field of paediatric oncology, in combination with other chemotherapeutics, have revolutionised clinical oncology and transformed cancer into a curable disease. However, even though combination chemotherapy, together with radiation, surgery and immunotherapy, can nowadays cure almost all types of cancer, we still fail to achieve this for a substantial proportion of patients. The understanding of differences in metabolism, pharmacokinetics, pharmacodynamics, and tumour biology between patients that can be cured and patients that cannot, builds the scientific basis for rational therapy improvements. Here, we summarise current knowledge of how tumour-specific and patient-specific factors can dictate resistance to nucleobase/nucleoside analogues, and which strategies of re-sensitisation exist. We revisit well-established hurdles to treatment efficacy, like the blood-brain barrier and reduced deoxycytidine kinase activity, but will also discuss the role of novel resistance factors, such as SAMHD1. A comprehensive appreciation of the complex mechanisms that underpin the failure of chemotherapy will hopefully inform future strategies of personalised medicine.
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Affiliation(s)
- Nikolaos Tsesmetzis
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | - Cynthia B J Paulin
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, 171 65 Stockholm, Sweden.
| | - Sean G Rudd
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, 171 65 Stockholm, Sweden.
| | - Nikolas Herold
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, 171 77 Stockholm, Sweden.
- Paediatric Oncology, Theme of Children's and Women's Health, Karolinska University Hospital Solna, 171 76 Stockholm, Sweden.
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ITPA Activity in Adults and Children Treated With or Without Azathioprine: Relationship Between TPMT Activity, Thiopurine Metabolites, and Co-medications. Ther Drug Monit 2018. [PMID: 28650902 DOI: 10.1097/ftd.0000000000000430] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The implication of inosine triphosphate pyrophosphatase (ITPA) on thiopurine drug response variability has been investigated but little data are available on its role on thiopurine metabolites. The ability of ITPA to modify the thiopurine metabolite levels is currently used to optimize azathioprine (AZA) therapy in relation to thiopurine S-methyltransferase (TPMT) activity, the aim of this study is to investigate ITPA phenotype in a large population and to evaluate the relation between ITPA and TPMT activities and thiopurine metabolites. METHODS ITPA activity was determined in 183 adults and 138 children with or without AZA therapy. 6-thioguanine nucleotides (6-TGN), 6-methylmercaptopurine nucleotides (6-MeMPN) levels, and ITPA as well as TPMT activities were measured in red blood cells. Using the Gaussian mixture model, distribution of ITPA activity was evaluated. Intraindividual variability and influence of age, sex, AZA treatment and associated co-medications on ITPA activity were also assessed. RESULTS This retrospective study shows a quadrimodal distribution in ITPA activity. No influence of age, sex, AZA therapy, and co-medications was found. In adults, ITPA activity was not significantly associated with 6-TGN or 6-MeMPN concentrations, whereas a weak negative correlation was observed with 6-MeMPN levels in pediatric populations (rs = -0.261; P = 0.024). A weak positive correlation was observed between ITPA and TPMT activities in children (rs = 0.289; P = 0.001). CONCLUSIONS ITPA activity was poorly influenced by nongenetic parameters and has no influence on 6-TGN and 6-MeMPN concentrations in adults and only a weak correlation with 6-MeMPN and TPMT activity in children. These results demonstrate that ITPA is not a rate-limiting enzyme in the formation of 6-TGN but suggest that a decrease in ITPA activity in children may be a risk factor for accumulation of 6-MeMPN in cells.
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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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Kakuta Y, Kinouchi Y, Shimosegawa T. Pharmacogenetics of thiopurines for inflammatory bowel disease in East Asia: prospects for clinical application of NUDT15 genotyping. J Gastroenterol 2018; 53:172-180. [PMID: 29192347 PMCID: PMC5846876 DOI: 10.1007/s00535-017-1416-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Accepted: 11/19/2017] [Indexed: 02/06/2023]
Abstract
The thiopurine drugs 6-mercaptopurine (6-MP) and azathiopurine (AZA) are widely used to treat inflammatory bowel disease. However, the incidence of adverse reactions is high, particularly in Asia, and the mechanisms of toxicity in Asian populations remain unclear. Thiopurine S-methyltransferase (TPMT) is a well-known enzyme that inactivates AZA or 6-MP through methylation and is one of the few pharmacogenetic predictors used in clinical settings in Western countries. Individuals carrying TPMT-deficient genetic variants require reduced drug doses, but this treatment modification is are not applicable to East Asian populations. Several genes code thiopurine-metabolizing enzymes, including TPMT, multidrug-resistance protein 4, and inosine triphosphatase. These genes have been studied as candidate pharmacogenetic markers; however, it remains unclear why Asian populations seem to be more intolerant than other ethnic groups to a full dose of thiopurines. A genome-wide association approach to identify Asian-specific pharmacogenetic markers in Korean patients with Crohn's disease revealed that a non-synonymous single nucelotide polymorphism in nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15) which causes p.Arg139Cys was strongly associated with thiopurine-induced early leukopenia. Six common haplotypes of NUDT15 were reported, and five variants showed medium-to-low enzyme activities, compared with the wild haplotype. NUDT15 hydrolyzes the thiopurine active metabolites 6-thio-GTP and 6-thio-dGTP; variants of NUDT15 had lower enzyme activities, causing higher levels of thiopurine active metabolites, resulting in thiopurine-induced leukopenia. In clinical application, NUDT15 genotyping is a good candidate for predicting thiopurine toxicity in East Asian populations. However, the association of NUDT15 diplotypes with thiopurine toxicity remains unclear. Further analyses with large cohorts to confirm the clinical effects of each haplotype are planned.
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Affiliation(s)
- Yoichi Kakuta
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, 1-1 Seiryo, Aoba, Sendai, 980-8574 Japan
| | - Yoshitaka Kinouchi
- Institute for Excellent in Higher Education, Tohoku University, Sendai, Japan
| | - Tooru Shimosegawa
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, 1-1 Seiryo, Aoba, Sendai, 980-8574 Japan
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11
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Coskun M, Steenholdt C, de Boer NK, Nielsen OH. Pharmacology and Optimization of Thiopurines and Methotrexate in Inflammatory Bowel Disease. Clin Pharmacokinet 2016; 55:257-74. [PMID: 26255287 DOI: 10.1007/s40262-015-0316-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Improving the efficacy and reducing the toxicity of thiopurines and methotrexate (MTX) have been areas of intense basic and clinical research. An increased knowledge on pharmacodynamics and pharmacokinetics of these immunomodulators has optimized treatment strategies in inflammatory bowel disease (IBD). This review focuses on the metabolism and mode of action of thiopurines and MTX, and provides an updated overview of individualized treatment strategies in which efficacy in IBD can be increased without compromising safety. The patient-based monitoring instruments adapted into clinical practice include pretreatment thiopurine S-methyltransferase testing, thiopurine metabolite monitoring, and blood count measurements that may help guiding the dosage to improve clinical outcome. Other approaches for optimizing thiopurine therapy in IBD include combination therapy with allopurinol, 5-aminosalicylates, and/or biologics. Similar strategies are yet to be proven effective in improving the outcome of MTX therapy. Important challenges for the management of IBD in the future relate to individualized dosing of immunomodulators for maximal efficacy with minimal risk of side effects. As low-cost conventional immunomodulators still remain a mainstay in pharmacotherapy of IBD, more research remains warranted, especially to substantiate these tailored management strategies in controlled clinical trials.
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Affiliation(s)
- Mehmet Coskun
- Department of Gastroenterology, Herlev Hospital, University of Copenhagen, Herlev, Denmark. .,Department of Biology and Biotech Research and Innovation Centre (BRIC), The Bioinformatics Centre, University of Copenhagen, Copenhagen, Denmark.
| | - Casper Steenholdt
- Department of Gastroenterology, Herlev Hospital, University of Copenhagen, Herlev, Denmark
| | - Nanne K de Boer
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, The Netherlands
| | - Ole Haagen Nielsen
- Department of Gastroenterology, Herlev Hospital, University of Copenhagen, Herlev, Denmark
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12
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Skrzypczak-Zielinska M, Borun P, Bartkowiak-Kaczmarek A, Zakerska-Banaszak O, Walczak M, Dobrowolska A, Kurzawski M, Waszak M, Lipinski D, Plawski A, Slomski R. A Simple Method for TPMT and ITPA Genotyping Using Multiplex HRMA for Patients Treated with Thiopurine Drugs. Mol Diagn Ther 2016; 20:493-9. [PMID: 27307154 PMCID: PMC5021755 DOI: 10.1007/s40291-016-0217-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Thiopurine methyltransferase (TPMT) and inosine triphosphatase (ITPA) are crucial enzymes involved in the metabolism of thiopurine drugs: azathioprine and 6-mercaptopurine, used in the treatment of leukemia or inflammatory bowel diseases (IBD). The activity in these enzymes correlates with the genetic polymorphism of the TPMT and ITPA genes, respectively, which determines an individual reaction and dosing of thiopurines. Three main TPMT alleles: TPMT*2 (c.238G>C), TPMT*3A (c.460G>A, c.719A>G) and TPMT*3C (c.719A>G) account for 80-95 % of inherited TPMT deficiency in different populations in the world. In the ITPA gene, a c.94C>A mutation is significantly associated with an adverse thiopurine reaction. The aim of this study was to develop a quick and highly sensitive method for determining major TPMT and ITPA alleles. Here we present the molecular test for genotyping c.238G>C, c.460G>A, c.719A>G and c.94C>A changes based on multiplex high resolution melting analysis (HRMA). We analyzed DNA samples from 100 clinically diagnosed IBD patients treated with thiopurine drugs, and a known genotype in the positions 238, 460 and 719 of the TPMT gene as well as in position 94 of the ITPA gene. Our results obtained with multiplex HRMA indicated 100 % accuracy in comparison with data from restriction fragments length polymorphism (RFLP) and standard DNA sequencing. We conclude, that multiplex HRMA can be used as a quick, sensitive and efficient alternative diagnostic method compared to conventional techniques for the determination of TPMT*2, TPMT*3A and TPMT*3C alleles and c.94C>A change in the ITPA gene.
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Affiliation(s)
| | - Pawel Borun
- Institute of Human Genetics, Polish Academy of Sciences, ul. Strzeszynska 32, 60-479, Poznan, Poland
| | - Anna Bartkowiak-Kaczmarek
- Laboratory of Cell Biophysics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Oliwia Zakerska-Banaszak
- Institute of Human Genetics, Polish Academy of Sciences, ul. Strzeszynska 32, 60-479, Poznan, Poland
| | - Michal Walczak
- Institute of Human Genetics, Polish Academy of Sciences, ul. Strzeszynska 32, 60-479, Poznan, Poland
| | - Agnieszka Dobrowolska
- Department of Gastroenterology, Human Nutrition and Internal Diseases, University of Medical Sciences, Poznan, Poland
| | - Mateusz Kurzawski
- Department of Experimental and Clinical Pharmacology, Pomeranian Medical University, Szczecin, Poland
| | - Malgorzata Waszak
- Department of Functional Anatomy, University School of Physical Education, Poznan, Poland
| | - Daniel Lipinski
- Department of Biochemistry and Biotechnology, University of Life Sciences, Poznan, Poland
| | - Andrzej Plawski
- Institute of Human Genetics, Polish Academy of Sciences, ul. Strzeszynska 32, 60-479, Poznan, Poland
| | - Ryszard Slomski
- Institute of Human Genetics, Polish Academy of Sciences, ul. Strzeszynska 32, 60-479, Poznan, Poland
- Department of Biochemistry and Biotechnology, University of Life Sciences, Poznan, Poland
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Pharmacogenetics and induction/consolidation therapy toxicities in acute lymphoblastic leukemia patients treated with AIEOP-BFM ALL 2000 protocol. THE PHARMACOGENOMICS JOURNAL 2015; 17:4-10. [PMID: 26644204 DOI: 10.1038/tpj.2015.83] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 09/24/2015] [Accepted: 11/02/2015] [Indexed: 12/14/2022]
Abstract
Drug-related toxicities represent an important clinical concern in chemotherapy, genetic variants could help tailoring treatment to patient. A pharmacogenetic multicentric study was performed on 508 pediatric acute lymphoblastic leukemia patients treated with AIEOP-BFM 2000 protocol: 28 variants were genotyped by VeraCode and Taqman technologies, deletions of GST-M1 and GST-T1 by multiplex PCR. Toxicities were derived from a central database: 251 patients (49.4%) experienced at least one gastrointestinal (GI) or hepatic (HEP) or neurological (NEU) grade III/IV episode during the remission induction phase: GI occurred in 63 patients (12.4%); HEP in 204 (40.2%) and NEU in 44 (8.7%). Logistic regression model adjusted for sex, risk and treatment phase revealed that ITPA rs1127354 homozygous mutated patients showed an increased risk of severe GI and NEU. ABCC1 rs246240 and ADORA2A rs2236624 homozygous mutated genotypes were associated to NEU and HEP, respectively. These three variants could be putative predictive markers for chemotherapy-related toxicities in AIEOP-BFM protocols.
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14
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Hoang PTV, Ambroise J, Dekairelle AF, Durant JF, Butoescu V, Chi VLD, Huynh N, Nguyen TB, Robert A, Vermylen C, Gala JL. Comparative pharmacogenetic analysis of risk polymorphisms in Caucasian and Vietnamese children with acute lymphoblastic leukemia: prediction of therapeutic outcome? Br J Clin Pharmacol 2015; 79:429-40. [PMID: 25099492 DOI: 10.1111/bcp.12481] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 08/04/2014] [Indexed: 01/10/2023] Open
Abstract
AIMS Acute lymphoblastic leukemia (ALL) is the most common of all paediatric cancers. Aside from predisposing to ALL, polymorphisms could also be associated with poor outcome. Indeed, genetic variations involved in drug metabolism could, at least partially, be responsible for heterogeneous responses to standardized leukemia treatments, hence requiring more personalized therapy. The aims of this study were to (a) to determine the prevalence of seven common genetic polymorphisms including those that affect the folate and/or thiopurine metabolic pathways, i.e. cyclin D1 (CCND1-G870A), γ-glutamyl hydrolase (GGH-C452T), methylenetetrahydrofolate reductase (MTHFR-C677T and MTHFR-A1298C), thymidylate synthase promoter (TYMS-TSER), thiopurine methyltransferase (TPMT*3A and TPMT*3C) and inosine triphosphate pyrophosphatase (ITPA-C94A), in Caucasian (n = 94, age < 20) and Vietnamese (n = 141, age < 16 years) childhood ALL and (b) to assess the impact of a multilocus genetic risk score (MGRS) on relapse-free survival (RFS) using a Cox proportional-hazards regression model. RESULTS The prevalence of MTHFR-677TT genotype was significantly higher in Caucasians (P = 0.008), in contrast to the prevalence of TYMS-TSER*3R/3R and ITPA-94AA/AC genotypes which were significantly higher in Vietnamese (P < 0.001 and P = 0.02, respectively). Compared with children with a low MGRS (≤ 3), those with a high MGRS (≥ 4) were 2.06 (95% CI = 1.01, 4.22; P = 0.04) times more likely to relapse. Adding MGRS into a multivariate Cox regression model with race/ethnicity and four clinical variables improved the predictive accuracy of the model (AUC from 0.682 to 0.709 at 24 months). CONCLUSION Including MGRS into a clinical model improved the predictive accuracy of short and medium term prognosis, hence confirming the association between well determined pharmacogenotypes and outcome of paediatric ALL. Whether variants on other genes associated with folate metabolism can substantially improve the predictive value of current MGRS is not known but deserves further evaluation.
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Affiliation(s)
- Phuong Thu Vu Hoang
- Centre de Technologies Moléculaires Appliquées (CTMA), Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCL), Brussels, Belgium; Service d'hématologie et oncologie pédiatrique, Cliniques universitaires Saint-Luc, Université catholique de Louvain (UCL), Brussels, Belgium; Pham Ngoc Thach University of Medecin, Ho Chi Minh city, Vietnam; Blood Transfusion and Hematology Hospital, Ho Chi Minh city, Vietnam
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15
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Frequency of ITPA gene polymorphisms in Iranian patients with acute lymphoblastic leukemia and prediction of its myelosuppressive effects. Leuk Res 2015; 39:1048-54. [DOI: 10.1016/j.leukres.2015.06.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 06/23/2015] [Accepted: 06/29/2015] [Indexed: 01/29/2023]
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16
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Suzuki R, Fukushima H, Noguchi E, Tsuchida M, Kiyokawa N, Koike K, Ma E, Takahashi H, Kobayashi C, Nakajima-Yamaguchi R, Sakai A, Saito M, Iwabuchi A, Kato K, Nakao T, Yoshimi A, Sumazaki R, Fukushima T. Influence of SLCO1B1 polymorphism on maintenance therapy for childhood leukemia. Pediatr Int 2015; 57:572-7. [PMID: 25939871 DOI: 10.1111/ped.12682] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 11/26/2014] [Accepted: 01/29/2015] [Indexed: 12/31/2022]
Abstract
BACKGROUND Management of the adverse effects of chemotherapy is essential to improve outcome of children with leukemia. Some genetic polymorphisms can predict treatment-related toxicity, and be used individually in dose modification of 6-mercaptopurine (6-MP) and methotrexate (MTX) in maintenance therapy for childhood acute lymphoblastic leukemia (ALL). We investigated associations between clinical course and candidate gene polymorphisms less evaluated in Japanese patients. METHODS Fifty-three children who received maintenance chemotherapy were enrolled in this study. The scheduled dose of oral 6-MP was 40 mg/m(2) daily and that of oral MTX was 25 mg/m(2) weekly. The doses were adjusted according to white blood cell count (target range, 2.5-3.5 × 10(9) /L) and aspartate aminotransferase and alanine aminotransferase level (< 750 IU/L). Eight polymorphisms in six candidate genes, TPMT, ITPA, MRP4, MTHFR, RFC1, and SLCO1B1, were genotyped using the Taqman PCR method. Clinical course was reviewed retrospectively from medical records. RESULTS The average dose of 6-MP was lower in the patients with at least one variant allele at SLCO1B1 c.521 T > C than in the patients with wild homozygous genotype. The other analyzed polymorphisms were not associated with toxicity, 6-MP, or MTX dose. CONCLUSIONS Polymorphism of SLCO1B1 c.521 T > C could be a strong predictor of 6-MP dose reduction in maintenance chemotherapy in childhood ALL.
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Affiliation(s)
- Ryoko Suzuki
- Department of Child Health, Graduate School of Comprehensive Human Sciences
| | | | | | - Masahiro Tsuchida
- Department of Hematology and Oncology, Ibaraki Children's Hospital, Mito, Ibaraki
| | - Nobutaka Kiyokawa
- Department of Pediatric Hematology and Oncology Research, National Research Institute for Child Health and Development, Setagaya-ku, Tokyo
| | - Kazutoshi Koike
- Department of Hematology and Oncology, Ibaraki Children's Hospital, Mito, Ibaraki
| | - Enbo Ma
- Clinical Trial and Clinical Epidemiology and
| | - Hideto Takahashi
- Epidemiology, Faculty of Medicine, University of Tsukuba.,School of Medicine, Information Management and Statistics, Fukushima Medical University, Fukushima, Japan
| | | | | | - Aiko Sakai
- Department of Child Health, Graduate School of Comprehensive Human Sciences
| | | | | | - Keisuke Kato
- Department of Hematology and Oncology, Ibaraki Children's Hospital, Mito, Ibaraki
| | - Tomohei Nakao
- Department of Hematology and Oncology, Ibaraki Children's Hospital, Mito, Ibaraki
| | - Ai Yoshimi
- Department of Hematology and Oncology, Ibaraki Children's Hospital, Mito, Ibaraki
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17
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Mei L, Ontiveros EP, Griffiths EA, Thompson JE, Wang ES, Wetzler M. Pharmacogenetics predictive of response and toxicity in acute lymphoblastic leukemia therapy. Blood Rev 2015; 29:243-9. [PMID: 25614322 DOI: 10.1016/j.blre.2015.01.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Revised: 12/26/2014] [Accepted: 01/06/2015] [Indexed: 12/19/2022]
Abstract
Acute lymphoblastic leukemia (ALL) is a relatively rare disease in adults accounting for no more than 20% of all cases of acute leukemia. By contrast with the pediatric population, in whom significant improvements in long term survival and even cure have been achieved over the last 30years, adult ALL remains a significant challenge. Overall survival in this group remains a relatively poor 20-40%. Modern research has focused on improved pharmacokinetics, novel pharmacogenetics and personalized principles to optimize the efficacy of the treatment while reducing toxicity. Here we review the pharmacogenetics of medications used in the management of patients with ALL, including l-asparaginase, glucocorticoids, 6-mercaptopurine, methotrexate, vincristine and tyrosine kinase inhibitors. Incorporating recent pharmacogenetic data, mainly from pediatric ALL, will provide novel perspective of predicting response and toxicity in both pediatric and adult ALL therapies.
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Affiliation(s)
- Lin Mei
- Leukemia Section, Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Evelena P Ontiveros
- Leukemia Section, Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Elizabeth A Griffiths
- Leukemia Section, Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - James E Thompson
- Leukemia Section, Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Eunice S Wang
- Leukemia Section, Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Meir Wetzler
- Leukemia Section, Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263, USA.
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18
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Li P, Chen Q, Wang YD, Ha MW. Effects of MTHFR Genetic Polymorphisms on Toxicity and Clinical Response of Irinotecan-Based Chemotherapy in Patients with Colorectal Cancer. Genet Test Mol Biomarkers 2014; 18:313-22. [PMID: 24611457 DOI: 10.1089/gtmb.2013.0494] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Ping Li
- Department of Oncology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou, People's Republic of China
| | - Quan Chen
- Department of Anesthesiology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou, People's Republic of China
| | - Ya-Di Wang
- Department of Oncology, The Third Affiliated Hospital of Liaoning Medical University, Jinzhou, People's Republic of China
| | - Min-Wen Ha
- Department of Oncology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou, People's Republic of China
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19
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Farfan MJ, Salas C, Canales C, Silva F, Villarroel M, Kopp K, Torres JP, Santolaya ME, Morales J. Prevalence of TPMT and ITPA gene polymorphisms and effect on mercaptopurine dosage in Chilean children with acute lymphoblastic leukemia. BMC Cancer 2014; 14:299. [PMID: 24774509 PMCID: PMC4012712 DOI: 10.1186/1471-2407-14-299] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 04/23/2014] [Indexed: 10/26/2022] Open
Abstract
BACKGROUND Mercaptopurine (6-MP) plays a pivotal role in treatment of childhood acute lymphoblastic leukemia (ALL); however, interindividual variability in toxicity of this drug due to genetic polymorphism in 6-MP metabolizing enzymes has been described. We determined the prevalence of the major genetic polymorphisms in 6-MP metabolizing enzymes in Chilean children with ALL. METHODS 103 Chilean pediatric patients with a confirmed diagnosis of ALL were enrolled. DNA was isolated from whole blood and genetic polymorphism in thiopurine S-methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) coding genes were detected by polymorphism chain reaction-restriction fragment length (PCR-RFLP) assay. RESULTS The total frequency of variant TPMT alleles was 8%. TPMT*2, TPMT*3A and TPMT*3B alleles were found in 0%, 7%, and 1% of patients, respectively. For ITPA, the frequency of P32T allele was 3%. We did not observe any homozygous variant for TPMT and ITPA alleles. We also analyzed a subgroup of 40 patients who completed the maintenance phase of ALL treatment, and we found that patients carrying a TPMT gene variant allele required a significantly lower median cumulative dosage and median daily dosage of 6-MP than patients carrying wild type alleles. CONCLUSION TMPT genotyping appears an important tool to further optimize 6-MP treatment design in Chilean patients with ALL.
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Affiliation(s)
- Mauricio J Farfan
- Departamento de Pediatría, Centro de Estudios Moleculares, Facultad de Medicina, Universidad de Chile, Antonio Varas 360, Santiago, Chile.
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Dulucq S, Laverdière C, Sinnett D, Krajinovic M. Pharmacogenetic considerations for acute lymphoblastic leukemia therapies. Expert Opin Drug Metab Toxicol 2014; 10:699-719. [PMID: 24673379 DOI: 10.1517/17425255.2014.893294] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Advances in our understanding of the pathobiology of childhood acute lymphoblastic leukemia (ALL) have led to risk-targeted treatment regimens and remarkable improvement in survival rates. Still, up to 20% of patients experience treatment failure due to drug resistance. Treatment-related toxicities are often life-threatening and are the primary cause of treatment interruption, while ALL survivors may develop complications due to exposure to chemotherapy and/or irradiation during a vulnerable period of development. Different factors may contribute to variable treatment outcomes including patient genetics that has been shown to play important role. AREAS COVERED This review summarizes candidate gene and genome-wide association studies that identified common polymorphisms underlying variability in treatment responses including a few studies addressing late effects of the treatment. Genetic variants influencing antileukemic drug effects or leukemic cell biology have been identified, including for example variants in folate-dependent enzymes, influx and efflux transporters, metabolizing enzymes, drug receptor or apoptotic proteins. EXPERT OPINION Many pharmacogenetic studies have been conducted in ALL and a variety of potential markers have been identified. Yet more comprehensive insight into genome variations influencing drug responses is needed. Whole exome/genome sequencing, careful study design, mechanistic explanation of association found and collaborative studies will ultimately lead to personalized treatment and improved therapeutic and health outcomes.
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Affiliation(s)
- Stéphanie Dulucq
- University Health Center Bordeaux, Heamatology Laboratory , Bordeaux , France
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21
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Deletion of glutathione-s-transferase m1 reduces azathioprine metabolite concentrations in young patients with inflammatory bowel disease. J Clin Gastroenterol 2014; 48:43-51. [PMID: 23787247 DOI: 10.1097/mcg.0b013e31828b2866] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
GOALS To investigate, in young patients with inflammatory bowel disease (IBD) treated with azathioprine, the association between genetic polymorphisms of thiopurine-S-methyl-transferase (TPMT), inosine-triphosphate-pyrophosphatase (ITPA), and glutathione-S-transferases (GST), involved in azathioprine metabolism, the concentration of the main metabolites of azathioprine, thioguanine nucleotides (TGNs) and the methylated nucleotides (MMPN), and the dose of the medication. BACKGROUND Azathioprine is widely used in IBD as an immunosuppressive agent, particularly to maintain remission in patients with steroid refractory disease. Azathioprine is a prodrug and requires conversion to its active form mercaptopurine, which has no intrinsic activity, and is activated by the enzymes of the purine salvage pathway to TGNs. Polymorphisms in genes of enzymes involved in azathioprine metabolism influence the efficacy and toxicity of treatment. STUDY Seventy-five young patients with IBD treated with azathioprine at least for 3 months were enrolled and genotyped for the selected genes; for these patients, TGN and MMPN metabolites were measured by high performance liquid chromatography in erythrocytes. RESULTS GST-M1 deletion was associated with lower TGN/dose ratio (P=0.0030), higher azathioprine dose requirement (P=0.022), and reduced response to therapy (P=0.0022). TPMT variant genotype was associated with lower MMPN concentration (P=0.0064) and increased TGN/dose ratio (P=0.0035). ITPA C94A polymorphism resulted in an increased MMPN concentration (P=0.037). CONCLUSIONS This study describes the effect of candidate genetic polymorphisms in TPMT, ITPA, and GST-M1 on azathioprine pharmacokinetics in IBD patients, showing, for the first time, relevant effects of GST-M1 genotype on azathioprine metabolites concentration.
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Simone PD, Pavlov YI, Borgstahl GEO. ITPA (inosine triphosphate pyrophosphatase): from surveillance of nucleotide pools to human disease and pharmacogenetics. Mutat Res 2013; 753:131-146. [PMID: 23969025 DOI: 10.1016/j.mrrev.2013.08.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/31/2013] [Accepted: 08/02/2013] [Indexed: 01/08/2023]
Abstract
Cellular nucleotide pools are often contaminated by base analog nucleotides which interfere with a plethora of biological reactions, from DNA and RNA synthesis to cellular signaling. An evolutionarily conserved inosine triphosphate pyrophosphatase (ITPA) removes the non-canonical purine (d)NTPs inosine triphosphate and xanthosine triphosphate by hydrolyzing them into their monophosphate form and pyrophosphate. Mutations in the ITPA orthologs in model organisms lead to genetic instability and, in mice, to severe developmental anomalies. In humans there is genetic polymorphism in ITPA. One allele leads to a proline to threonine substitution at amino acid 32 and causes varying degrees of ITPA deficiency in tissues and plays a role in patients' response to drugs. Structural analysis of this mutant protein reveals that the protein is destabilized by the formation of a cavity in its hydrophobic core. The Pro32Thr allele is thought to cause the observed dominant negative effect because the resulting active enzyme monomer targets both homo- and heterodimers to degradation.
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Affiliation(s)
- Peter D Simone
- The Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Youri I Pavlov
- The Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, USA; Department of Pathology and Microbiology, University of Nebraska Medical Center, USA; Department of Genetics, St-Petersburg University, St-Petersburg, 199034, Russia
| | - Gloria E O Borgstahl
- The Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, USA; Department of Pharmaceutical Sciences, University of Nebraska Medical Center, USA.
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Karim H, Ghalali A, Lafolie P, Vitols S, Fotoohi AK. Differential role of thiopurine methyltransferase in the cytotoxic effects of 6-mercaptopurine and 6-thioguanine on human leukemia cells. Biochem Biophys Res Commun 2013; 437:280-6. [PMID: 23811272 DOI: 10.1016/j.bbrc.2013.06.067] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 06/18/2013] [Indexed: 11/24/2022]
Abstract
The thiopurine antimetabolites, 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG) are inactive pro-drugs that require intracellular metabolism for activation to cytotoxic metabolites. Thiopurine methyltransferase (TPMT) is one of the most important enzymes in this process metabolizing both 6-MP and 6-TG to different methylated metabolites including methylthioinosine monophosphate (meTIMP) and methylthioguanosine monophosphate (meTGMP), respectively, with different suggested pharmacological and cytotoxic properties. While meTIMP is a potent inhibitor of de novo purine synthesis (DNPS) and significantly contributes to the cytotoxic effects of 6-MP, meTGMP, does not add much to the effects of 6-TG, and the cytotoxicity of 6-TG seems to be more dependent on incorporation of thioguanine nucleotides (TGNs) into DNA rather than inhibition of DNPS. In order to investigate the role of TPMT in metabolism and thus, cytotoxic effects of 6-MP and 6-TG, we knocked down the expression of the gene encoding the TPMT enzyme using specifically designed small interference RNA (siRNA) in human MOLT4 leukemia cells. The knock-down was confirmed at RNA, protein, and enzyme function levels. Apoptosis was determined using annexin V and propidium iodide staining and FACS analysis. The results showed a 34% increase in sensitivity of MOLT4 cells to 1μM 6-TG after treatment with TPMT-targeting siRNA, as compared to cells transfected with non-targeting siRNA, while the sensitivity of the cells toward 6-MP was not affected significantly by down-regulation of the TPMT gene. This differential contribution of the enzyme TPMT to the cytotoxicity of the two thiopurines is probably due to its role in formation of the meTIMP, the cytotoxic methylated metabolite of 6-MP, while in case of 6-TG methylation by TPMT substantially deactivates the drug.
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Affiliation(s)
- Hazhar Karim
- Department of Medicine, Clinical Pharmacology Unit, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
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Stocco G, Franca R, Verzegnassi F, Londero M, Rabusin M, Decorti G. Multilocus genotypes of relevance for drug metabolizing enzymes and therapy with thiopurines in patients with acute lymphoblastic leukemia. Front Genet 2013; 3:309. [PMID: 23335936 PMCID: PMC3538559 DOI: 10.3389/fgene.2012.00309] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 12/12/2012] [Indexed: 12/31/2022] Open
Abstract
Multilocus genotypes have been shown to be of relevance for using pharmacogenomic principles to individualize drug therapy. As it relates to thiopurine therapy, genetic polymorphisms of TPMT are strongly associated with the pharmacokinetics and clinical effects of thiopurines (mercaptopurine and azathioprine), influencing their toxicity and efficacy. We have recently demonstrated that TPMT and ITPA genotypes constitute a multilocus genotype of pharmacogenetic relevance for children with acute lymphoblastic leukemia (ALL) receiving thiopurine therapy. The use of high-throughput genomic analysis allows identification of additional candidate genetic factors associated with pharmacogenetic phenotypes, such as TPMT enzymatic activity: PACSIN2 polymorphisms have been identified by a genome-wide analysis, combining evaluation of polymorphisms and gene expression, as a significant determinant of TPMT activity in the HapMap CEU cell lines and the effects of PACSIN2 on TPMT activity and mercaptopurine induced adverse effects were confirmed in children with ALL. Combination of genetic factors of relevance for thiopurine metabolizing enzyme activity, based on the growing understanding of their association with drug metabolism and efficacy, is particularly promising for patients with pediatric ALL. The knowledge basis and clinical applications for multilocus genotypes of importance for therapy with mercaptopurine in pediatric ALL is discussed in the present review.
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Affiliation(s)
- Gabriele Stocco
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital Memphis, TN, USA ; Department of Life Sciences, University of Trieste Trieste, Italy
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Corrigan A, Arenas-Hernandez M, Blaker P, Sanderson J, Marinaki A. Let's get personal: predicting thiopurine and fluoropyrimidine toxicity. Per Med 2012; 9:859-870. [PMID: 29776234 DOI: 10.2217/pme.12.91] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The US FDA now recognizes the need to individualize treatment paradigms using biomarkers that predict response to therapy. In clinical practice the best example of this is TPMT testing, which is used to rationalize the starting dose of azathioprine and mercaptopurine. The more recent addition of drug metabolite monitoring means that thiopurine therapy can now be personalized to unprecedented levels. Of interest, parallels exist between TPMT deficiency as an explanation for thiopurine toxicity and DPD deficiency in fluoropyrimidine toxicity. For these drugs, variations in a single locus predict severe toxicity. However, while TPMT testing has translated into routine clinical practice, DPD testing has not. This article summarizes the recent research investigating interindividual differences in the metabolism of thiopurine and fluoropyrimidine drugs, and explores the attitudes which influence the uptake of pharmacogenetic testing.
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Affiliation(s)
- Adele Corrigan
- Purine Research Laboratory, GSTS Pathology, Guy's & St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH, UK
| | - Monica Arenas-Hernandez
- Purine Research Laboratory, GSTS Pathology, Guy's & St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH, UK
| | - Paul Blaker
- Department of Gastroenterology, 1st Floor College House, St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH, UK
| | - Jeremy Sanderson
- Department of Gastroenterology, 1st Floor College House, St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH, UK
| | - Anthony Marinaki
- Purine Research Laboratory, GSTS Pathology, Guy's & St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH, UK.
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Crona D, Innocenti F. Can knowledge of germline markers of toxicity optimize dosing and efficacy of cancer therapy? Biomark Med 2012; 6:349-62. [PMID: 22731909 DOI: 10.2217/bmm.12.19] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The systemic treatment of cancer with traditional cytotoxic chemotherapeutic agents and more targeted agents is often complicated by the onset of adverse drug reactions. Pharmacogenetic prediction of adverse drug reactions might have consequences for dosing and efficacy. This review discusses relevant examples where the germline variant-toxicity relationship has been validated as an initial step in developing clinically useful pharmacogenetic markers and provides examples where germline variants have influenced dosing strategies and/or survival or other outcomes of efficacy. This review will also provide insight into the reasons why more pharmacogenetic markers have not been routinely integrated into clinical practice.
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Affiliation(s)
- Daniel Crona
- Institute for Pharmacogenomics and Individualized Therapy, University of North Carolina, Chapel Hill, USA
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Kim H, Kang HJ, Kim HJ, Jang MK, Kim NH, Oh Y, Han BD, Choi JY, Kim CW, Lee JW, Park KD, Shin HY, Ahn HS. Pharmacogenetic analysis of pediatric patients with acute lymphoblastic leukemia: a possible association between survival rate and ITPA polymorphism. PLoS One 2012; 7:e45558. [PMID: 23029095 PMCID: PMC3454425 DOI: 10.1371/journal.pone.0045558] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 08/21/2012] [Indexed: 01/21/2023] Open
Abstract
Genetic polymorphisms are important factors in the effects and toxicity of chemotherapeutics. To analyze the pharmacogenetic and ethnic differences in chemotherapeutics, major genes implicated in the treatment of acute lymphoblastic leukemia (ALL) were analyzed. Eighteen loci of 16 genes in 100 patients with ALL were analyzed. The distribution of variant alleles were CYP3A4*1B (0%), CYP3A5*3 (0%), GSTM1 (21%), GSTP1 (21%), GSTT1 (16%), MDR1 exon 21 (77%), MDR1 exon 26 (61%), MTHFR 677 (63%), MTHFR 1298 (29%), NR3C1 1088 (0%), RFC1 80 (68%), TPMT combined genotype (7%), VDR intron 8 (11%), VDR FokI (83%), TYMS enhancer repeat (22%) and ITPA 94 (30%). The frequencies of single nucleotide polymorphisms (SNPs) of 10 loci were statistically different from those in Western Caucasians. Dose percents (actual/planned dose) or toxicity of mercaptopurine and methotrexate were not related to any SNPs. Event free survival (EFS) rate was lower in ITPA variants, and ITPA 94 AC/AA variant genotypes were the only independent risk factor for lower EFS in multivariate analysis, which was a different pharmacogenetic implication from Western studies. This study is the first pharmacogenetic study in Korean pediatric ALL. Our result suggests that there are other possible pharmacogenetic factors besides TPMT or ITPA polymorphisms which influence the metabolism of mercaptopurine in Asian populations.
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Affiliation(s)
- Hyery Kim
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
- Department of Pediatrics, Seoul National University College of Medicine, SMG-SNU Boramae Medical Center, Seoul, Korea
| | - Hyoung Jin Kang
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
- * E-mail:
| | - Hyo Jeong Kim
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Mi Kyung Jang
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Nam Hee Kim
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | | | | | - Ji-Yeob Choi
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Chul Woo Kim
- Department of Pathology, Seoul National University College of Medicine, Seoul, Korea
| | - Ji Won Lee
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Kyung Duk Park
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Hee Young Shin
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Hyo Seop Ahn
- Department of Pediatrics, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
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Blaker PA, Arenas-Hernandez M, Marinaki AM, Sanderson JD. The pharmacogenetic basis of individual variation in thiopurine metabolism. Per Med 2012; 9:707-725. [DOI: 10.2217/pme.12.85] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Thiopurines are an important class of immunosuppressive therapy, which have been used in clinical practice for over 50 years. Despite this extensive experience many of the pharmacodynamic and pharmacokinetic properties of these drugs remain unknown. As a consequence there is often no clear explanation for the individual variation in response to treatment, both in terms of efficacy or adverse drug reactions. This review, which emphasizes practice in gastroenterology, summarizes the current understanding of thiopurine drug metabolism and highlights the role of nongenetic and genetic factors other than TPMT, which should be a focus for future research. Correlation of polymorphic variations in these genes with clinical outcomes is expected to clarify the basis for interindividual differences in thiopurine metabolism and enable a more personalized approach to therapy.
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Affiliation(s)
- Paul Andrew Blaker
- Department of Gastroenterology, 1st Floor College House, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, London, UK
| | - Monica Arenas-Hernandez
- The Purine Research Laboratory, Guy’s & St Thomas’ Hospitals NHS Foundation Trust , London, UK
| | - Anthony Marin Marinaki
- The Purine Research Laboratory, Guy’s & St Thomas’ Hospitals NHS Foundation Trust , London, UK
| | - Jeremy David Sanderson
- Department of Gastroenterology, 1st Floor College House, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, London, UK
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Abstract
The amazing successes in cure rates for children with cancer over the last century have come in large part from identifying clinical, genetic, and molecular variables associated with response to therapy in large cooperative clinical trials and stratifying therapies according to the predicted risk of relapse. There is an expanding interest in identifying germline genomic variants, as opposed to genetic variants within the tumor, that are associated with susceptibility to toxicity and for risk of relapse. This review highlights the most important germline pharmacogenetic and pharmacogenomic studies in pediatric oncology. Incorporating germline genomics into risk-adapted therapies will likely lead to safer and more effective treatments for children with cancer.
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Affiliation(s)
- Navin Pinto
- Department of Pediatrics and Medicine, and Committee on Clinical Pharmacology and Pharmacogenomics, University of Chicago, Chicago, Illinois 60637, USA.
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Defects in purine nucleotide metabolism lead to substantial incorporation of xanthine and hypoxanthine into DNA and RNA. Proc Natl Acad Sci U S A 2012; 109:2319-24. [PMID: 22308425 DOI: 10.1073/pnas.1118455109] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Deamination of nucleobases in DNA and RNA results in the formation of xanthine (X), hypoxanthine (I), oxanine, and uracil, all of which are miscoding and mutagenic in DNA and can interfere with RNA editing and function. Among many forms of nucleic acid damage, deamination arises from several unrelated mechanisms, including hydrolysis, nitrosative chemistry, and deaminase enzymes. Here we present a fourth mechanism contributing to the burden of nucleobase deamination: incorporation of hypoxanthine and xanthine into DNA and RNA caused by defects in purine nucleotide metabolism. Using Escherichia coli and Saccharomyces cerevisiae with defined mutations in purine metabolism in conjunction with analytical methods for quantifying deaminated nucleobases in DNA and RNA, we observed large increases (up to 600-fold) in hypoxanthine in both DNA and RNA in cells unable to convert IMP to XMP or AMP (IMP dehydrogenase, guaB; adenylosuccinate synthetase, purA, and ADE12), and unable to remove dITP/ITP and dXTP/XTP from the nucleotide pool (dITP/XTP pyrophosphohydrolase, rdgB and HAM1). Conversely, modest changes in xanthine levels were observed in RNA (but not DNA) from E. coli lacking purA and rdgB and the enzyme converting XMP to GMP (GMP synthetase, guaA). These observations suggest that disturbances in purine metabolism caused by known genetic polymorphisms could increase the burden of mutagenic deaminated nucleobases in DNA and interfere with gene expression and RNA function, a situation possibly exacerbated by the nitrosative stress of concurrent inflammation. The results also suggest a mechanistic basis for the pathophysiology of human inborn errors of purine nucleotide metabolism.
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Hofmann U, Heinkele G, Angelberger S, Schaeffeler E, Lichtenberger C, Jaeger S, Reinisch W, Schwab M. Simultaneous quantification of eleven thiopurine nucleotides by liquid chromatography-tandem mass spectrometry. Anal Chem 2012; 84:1294-301. [PMID: 22220820 DOI: 10.1021/ac2031699] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The prodrugs azathioprine and 6-mercaptopurine, which are well-established anticancer and immunosuppressive agents, are extensively metabolized by activating and inactivating enzymes. Whereas the 6-thioguanine nucleotides (TGN) are currently being considered as major active metabolites, methylthioinosine nucleotides seem to contribute to the cytotoxic effect as well. Thiopurine-related adverse drug reactions and thiopurine failure are frequent. Thus, therapeutic monitoring of TGN and methylthioinosine derivatives has been suggested to improve thiopurine therapy, however with limited success. To elucidate systematically underlying molecular mechanisms as potential explanation for interindividual variability of thiopurine response, we developed a novel highly specific and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous quantitation of eleven mono-, di-, and triphosphates of thioguanosine, methylthioinosine, methylthioguanosine, and thioinosine. Using stable isotope-labeled analogues as internal standards obtained by chemical synthesis, an intra- and interassay variability below 8% and an accuracy of 92% to 107% were achieved in spiked quality control samples with known standards. All eleven metabolites could be determined in red blood cells from patients with inflammatory bowel diseases and long-term azathioprine therapy. Thus, our novel method opens a new avenue for the understanding of the thiopurine metabolism by quantitation of all important thiopurine nucleotide metabolites in one run.
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Affiliation(s)
- Ute Hofmann
- Dr Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
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Chouchana L, Narjoz C, Beaune P, Loriot MA, Roblin X. Review article: the benefits of pharmacogenetics for improving thiopurine therapy in inflammatory bowel disease. Aliment Pharmacol Ther 2012; 35:15-36. [PMID: 22050052 DOI: 10.1111/j.1365-2036.2011.04905.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Thiopurines represent an effective and widely prescribed therapy in inflammatory bowel disease (IBD). Concerns about toxicity, mainly resulting from a wide inter-individual variability in thiopurine metabolism, restrict their use. Optimal thiopurine dosing is challenging for preventing adverse drug reactions and improving clinical response. AIM To review efficacy and toxicity of thiopurines in IBD. To provide pharmacogenetic-based therapeutic recommendations. METHODS We conducted a query on PubMed database using 'inflammatory bowel disease', 'thiopurine', 'azathioprine', '6-mercaptopurine', 'TPMT', 'pharmacogenetics', 'TDM', and selected relevant articles, especially clinical studies. RESULTS Thiopurine metabolism - key enzyme: thiopurine S-methyltransferase (TPMT) - modulates clinical response, as it results in production of the pharmacologically active and toxic metabolites, the thioguanine nucleotides (6-TGN). Adjusting dosage according to TPMT status and/or metabolite blood levels is recommended for optimising thiopurine therapy (e.g. improving response rate up to 30% or decreasing haematological adverse events of 25%). Other enzymes or transporters of interest, as inosine triphosphatase (ITPase), glutathione S-transferase (GST), xanthine oxidase (XO), aldehyde oxidase (AOX), methylene tetrahydrofolate reductase (MTHFR) and ATP-binding cassette sub-family C member 4 (ABCC4) are reviewed and discussed for clinical relevance. CONCLUSIONS Based on the literature data, we provide a therapeutic algorithm for thiopurines therapy with starting dose recommendations depending on TPMT status and thereafter dose adjustments according to five metabolite profiles identified with therapeutic drug monitoring (TDM). This algorithm allows a dosage individualisation to optimise the management of patients under thiopurine. Furthermore, identification of new pharmacogenetic biomarkers is promising for ensuring maximal therapeutic response to thiopurines with a minimisation of the risk for adverse events.
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Affiliation(s)
- L Chouchana
- Assistance publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Biochimie, Pharmacogénétique et Oncologie Moléculaire, Paris, France
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Tanaka Y, Manabe A, Nakadate H, Kondoh K, Nakamura K, Koh K, Utano T, Kikuchi A, Komiyama T. The activity of the inosine triphosphate pyrophosphatase affects toxicity of 6-mercaptopurine during maintenance therapy for acute lymphoblastic leukemia in Japanese children. Leuk Res 2011; 36:560-4. [PMID: 22200619 DOI: 10.1016/j.leukres.2011.11.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 10/24/2011] [Accepted: 11/22/2011] [Indexed: 01/29/2023]
Abstract
The association between inosine triphosphate pyrophosphatase (ITPA) activity and toxicity of 6-mercaptopurine (6-MP) was retrospectively evaluated in 65 Japanese children with acute lymphoblastic leukemia (ALL). Patients with an ITPA activity of less than 126 μmol/h/gHb presented with hepatotoxicity more frequently than those with higher ITPA activity (p<0.01). The average 6-MP dose during maintenance therapy administered to two patients with the ITPA deficiency was lower than that given to the other patients. Measuring ITPA activity is important for ensuring the safety of maintenance therapy for Asians with ALL because thiopurine S-methyl transferase mutations are rare in the Asian population.
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Affiliation(s)
- Yoichi Tanaka
- Department of Clinical Pharmacy, Center for Clinical Pharmacy and Sciences, School of Pharmacy, Kitasato University, Tokyo, Japan.
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Elie V, de Beaumais T, Fakhoury M, Jacqz-Aigrain E. Pharmacogenetics and individualized therapy in children: immunosuppressants, antidepressants, anticancer and anti-inflammatory drugs. Pharmacogenomics 2011; 12:827-43. [PMID: 21692614 DOI: 10.2217/pgs.11.19] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Pharmacogenetic polymorphisms that change the amino acid sequences in coding regions only account for part of the interindividual differences in disease susceptibility and drug response. Additional pharmacogenomic and epigenetic factors are also involved. In children, pharmacogenetic studies are limited, although it has been clear for many years that the interactions between developmental patterns of drug-metabolizing enzymes and transporters have a major impact on dose exposure with age-specific dosage requirements. This article will analyze the factors affecting variability in drug response in children and focus on the pharmacogenetic polymorphisms of immunosuppressants, antidepressants, anticancer and anti-inflammatory drugs. Additional pharmacogenetic and epigenetic studies should be performed to allow the individualization of therapy in children.
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Affiliation(s)
- Valery Elie
- Department of Paediatric Pharmacology & Pharmacogenetics, Assistance Publique Hopitaux de Paris, Clinical Investigation Center APHP-Inserm CIC9202, University Paris VII Diderot, Hopital Robert Debré, 48 Boulevard Serurier, 75019 Paris, France
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Bridging the efficacy-effectiveness gap: a regulator's perspective on addressing variability of drug response. Nat Rev Drug Discov 2011; 10:495-506. [PMID: 21720406 DOI: 10.1038/nrd3501] [Citation(s) in RCA: 209] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Drug regulatory agencies should ensure that the benefits of drugs outweigh their risks, but licensed medicines sometimes do not perform as expected in everyday clinical practice. Failure may relate to lower than anticipated efficacy or a higher than anticipated incidence or severity of adverse effects. Here we show that the problem of benefit-risk is to a considerable degree a problem of variability in drug response. We describe biological and behavioural sources of variability and how these contribute to the long-known efficacy-effectiveness gap. In this context, efficacy describes how a drug performs under conditions of clinical trials, whereas effectiveness describes how it performs under conditions of everyday clinical practice. We argue that a broad range of pre- and post-licensing technologies will need to be harnessed to bridge the efficacy-effectiveness gap. Successful approaches will not be limited to the current notion of pharmacogenomics-based personalized medicines, but will also entail the wider use of electronic health-care tools to improve drug prescribing and patient adherence.
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Karim H, Hashemi J, Larsson C, Moshfegh A, Fotoohi AK, Albertioni F. The pattern of gene expression and gene dose profiles of 6-Mercaptopurine- and 6-Thioguanine-resistant human leukemia cells. Biochem Biophys Res Commun 2011; 411:156-61. [PMID: 21723252 DOI: 10.1016/j.bbrc.2011.06.120] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 06/17/2011] [Indexed: 11/25/2022]
Abstract
Exposure of MOLT4 human T-cell leukemia cells to 6-Mercaptopurine (6-MP) and 6-Thioguanine (6-TG) resulted in acquired resistance associated with attenuated expression of the genes encoding concentrative nucleoside transporter 3 (CNT3) and equilibrative nucleoside transporter 2 (ENT2). To identify other alterations at the RNA and DNA levels associated with 6-MP- and 6-TG resistance, we compared here the patterns of gene expression and DNA copy number profiles of resistant sublines to those of the parental wild-type cells. The mRNA levels for two nucleoside transporters were down-regulated in both of the thiopurine-resistant sublines. Moreover, both of these cell lines expressed genes encoding the enzymes of purine nucleotide composition and synthesis, including adenylate kinase 3-like 1 and guanosine monophosphate synthetase at significantly lower levels than wild-type cells. In addition, expression of the mRNA for a specialized DNA polymerase, human terminal transferase encoded by the terminal deoxynucleotidyl transferase (DNTT) gene, was 122- and 93-fold higher in 6-TG- and 6-MP-resistant cells, respectively. The varying responses to 6-MP- and 6-TG observed here may help identify novel cellular targets and modalities of resistance to thiopurines, as well as indicating new potential approaches to individualization therapy with these drugs.
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Affiliation(s)
- Hazhar Karim
- Department of Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Karolinska University Hospital, SE-171 76 Stockholm, Sweden
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Adam de Beaumais T, Fakhoury M, Medard Y, Azougagh S, Zhang D, Yakouben K, Jacqz-Aigrain E. Determinants of mercaptopurine toxicity in paediatric acute lymphoblastic leukemia maintenance therapy. Br J Clin Pharmacol 2011; 71:575-84. [PMID: 21395650 DOI: 10.1111/j.1365-2125.2010.03867.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
AIMS 6-mercaptopurine (6-MP) is used in the treatment of childhood acute lymphoblastic leukaemia (ALL). Its red blood cell (RBC) metabolite concentrations (6-thioguanine [6-TGN] and 6-methylmercaptopurine nucleotides [6-MMPN]) are related to drug response. We investigated the impact of non-genetic covariates and pharmacogenetic polymorphisms affecting thiopurine methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) on 6-MP metabolism and response. METHODS Sixty-six children with ALL treated according to EORTC 58951 protocol were included in this study. Six patients had a heterozygous genotype for the most common TPMT polymorphisms, nine for ITPA 94 C > A and 17 for ITPA IVS2+21 A > C. 6-MP metabolites concentrations were analyzed by mixed model analysis. RESULTS During maintenance, steady-state RBC 6-TGN concentrations were lower in patients aged 6 years or younger (493 pmol/8 × 10(8) RBC) than in older children (600 pmol/8 × 10(8) RBC). 6-MMPN concentrations were low in patients with TPMT variant/wild-type ITPA (1862 pmol/8 × 10(8) RBC), intermediate in wild-type patients and high (16468 pmol/8 × 10(8) RBC) in patients wild-type TPMT/variant ITPA. A 6-MMPN threshold of 5000 pmol/8 × 10(8) RBC was associated with an increased risk of hepatotoxicity. CONCLUSION In this study, age and both TPMT and ITPA genotypes influenced 6-MP metabolism. High 6-MMPN was associated with hepatotoxicity. These pharmacological tools should be used to monitor ALL treatment in children.
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Abstract
OBJECTIVES To review pharmacogenetics as it relates to cancer therapy and to describe pharmacogenetic tests that are clinically available and relevant to cancer drug selection or dosing or both. DATA SOURCES Peer-reviewed, evidence-based literature. CONCLUSIONS Genetic predispositions and enzyme specific inhibitors and inducers are critical factors in patients' responses to cancer drugs. IMPLICATIONS FOR NURSING PRACTICE Nurses need to incorporate knowledge about pharmacogenetics when administering cancer drugs and monitoring patients' responses. Nurses also have an important role in assuring that patients are informed about the purpose and limitations of pharmacogenetic testing.
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Affiliation(s)
- Cynthia A Prows
- Children’s Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH 45229-3039, USA.
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40
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Abstract
PURPOSE OF REVIEW The therapeutic index of many medications, especially in children, is very narrow with substantial risk for toxicity at doses required for therapeutic effects. This is particularly relevant to cancer chemotherapy, when the risk of toxicity must be balanced against potential suboptimal (low) systemic exposure that can be less effective in patients with higher rates of drug clearance. The purpose of this review is to discuss genetic factors that lead to interpatient differences in the pharmacokinetics and pharmacodynamics of these medications. RECENT FINDINGS Genome-wide agonistic studies of pediatric patient populations are revealing genome variations that may affect susceptibility to specific diseases and that influence the pharmacokinetic and pharmacodynamic characteristics of medications. Several genetic factors with relatively small effect may be combined in the determination of a pharmacogenomic phenotype and considering these polygenic models may be mandatory in order to predict the related drug response phenotypes. These findings have potential to yield new insights into disease pathogenesis, and lead to molecular diagnostics that can be used to optimize the treatment of childhood cancers. SUMMARY Advances in genome technology, and their comprehensive and systematic deployment to elucidate the genomic basis of interpatient differences in drug response and disease risk, hold great promise to ultimately enhance the efficacy and reduce the toxicity of drug therapy in children.
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Affiliation(s)
- Steven W. Paugh
- Hematological Malignancies Program and Department of Pharmaceutical Sciences, St. Jude Children’s Research Hospital, Memphis, TN 38105
| | - Gabriele Stocco
- Hematological Malignancies Program and Department of Pharmaceutical Sciences, St. Jude Children’s Research Hospital, Memphis, TN 38105
| | - William E. Evans
- Hematological Malignancies Program and Department of Pharmaceutical Sciences, St. Jude Children’s Research Hospital, Memphis, TN 38105
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The role of the ADRA2A C1291G genetic polymorphism in response to dexmedetomidine on patients undergoing coronary artery surgery. Mol Biol Rep 2010; 38:3383-9. [PMID: 21104443 DOI: 10.1007/s11033-010-0446-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 11/08/2010] [Indexed: 10/18/2022]
Abstract
The existence of interindividual drug response variability has been known for a long time. Individual susceptibility which might cause toxicity or inadequate treatment is important in drug therapy. Genetic polymorphisms in genes responsible for drug response are expected to be useful in keeping track of differences among individuals. Dexmedetomidine is a sedative drug, whose use in intensive care unit patients was confirmed by USA-Food Drug Administration (FDA) by the end of 1999. It was proven that dexmedetomidine shows its clinic effect via the α(2)-AR. However, to the best of our knowledge, to date, there is no investigation in clinic indicating the relation between dexmedetomidine and α(2A)-AR gene polymorphism. The aim of our study was to investigate the association between the effect of α(2A)-Adrenergic Receptor (ADRA2A) C-1291G gene polymorphism in the promoter region of the candidate gene and clinical effects (sedative and haemodynamics effects) of dexmedetomidine. One hundred and ten patients undergoing coronary artery surgery were prospectively studied. Anesthetic technique was standardized with fentanyl, midazolam and rocuronium bromide. Patients were monitorized with Bispectral Index (BIS) monitor in addition to the routine invasive haemodynamic monitorization in the operation room. The Ramsay Sedation Scale was also used in order to determine the sedation level just arriving to Intensive Care Unit (ICU). The genotyping of ADRA2A C1291G was done by Restriction Fragment Length Polymorphism-Polymerase Chain Reaction (RFLP-PCR). We found the frequencies of C1291C, C1291G and G1291G genotypes, as 43.6, 45.5 and 10.9%, respectively. Patients who carry variant genotype had higher BIS and Ramsay Sedation Scores, indicating a longer period for falling asleep. The results of our study are promising, considering the association between ADRA2A polymorphism and response to dexmedetomidine. However, further investigations on other ADRA2A locus or haplotypes might be useful to clarify the relation between this gene and dexmedetomidine activity.
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[Azathioprine-associated severe myelosuppression: indication of routine determination of thiopurine S-methyltransferase variant?]. Rev Med Interne 2010; 32:373-6. [PMID: 20970225 DOI: 10.1016/j.revmed.2010.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Revised: 09/16/2010] [Accepted: 09/20/2010] [Indexed: 01/06/2023]
Abstract
INTRODUCTION Myelotoxicity is a well-known adverse effect of azathioprine, leading mainly to leukopenia. Other azathioprine associated hematological adverse effects are uncommon. CASE REPORT We report a 49-year-old woman with rheumatoid arthritis and acquired hemophilia, who presented a severe myelosuppression occurring 3 weeks after an increase of her azathioprine regimen (at a daily dose of 150 mg). The patient had a heterozygous mutation of the thiopurine S-methyltransferase gene (TPMT*3A). Azathioprine therapy was discontinued and she recovered at 3 weeks. The patient had no relapse of pancytopenia after a 1 year follow-up. CONCLUSION Routine measurement of TPMT activity or determination of TPMT variant allele may be useful tests, in order to identify the subgroup of patients who are at risk to develop azathioprine induced severe myelosuppression.
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Meeker ND, Yang JJ, Schiffman JD. Pharmacogenomics of pediatric acute lymphoblastic leukemia. Expert Opin Pharmacother 2010; 11:1621-32. [DOI: 10.1517/14656566.2010.484019] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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