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Fu Y, Aganezov S, Mahmoud M, Beaulaurier J, Juul S, Treangen TJ, Sedlazeck FJ. MethPhaser: methylation-based long-read haplotype phasing of human genomes. Nat Commun 2024; 15:5327. [PMID: 38909018 PMCID: PMC11193733 DOI: 10.1038/s41467-024-49588-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 06/11/2024] [Indexed: 06/24/2024] Open
Abstract
The assignment of variants across haplotypes, phasing, is crucial for predicting the consequences, interaction, and inheritance of mutations and is a key step in improving our understanding of phenotype and disease. However, phasing is limited by read length and stretches of homozygosity along the genome. To overcome this limitation, we designed MethPhaser, a method that utilizes methylation signals from Oxford Nanopore Technologies to extend Single Nucleotide Variation (SNV)-based phasing. We demonstrate that haplotype-specific methylations extensively exist in Human genomes and the advent of long-read technologies enabled direct report of methylation signals. For ONT R9 and R10 cell line data, we increase the phase length N50 by 78%-151% at a phasing accuracy of 83.4-98.7% To assess the impact of tissue purity and random methylation signals due to inactivation, we also applied MethPhaser on blood samples from 4 patients, still showing improvements over SNV-only phasing. MethPhaser further improves phasing across HLA and multiple other medically relevant genes, improving our understanding of how mutations interact across multiple phenotypes. The concept of MethPhaser can also be extended to non-human diploid genomes. MethPhaser is available at https://github.com/treangenlab/methphaser .
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Affiliation(s)
- Yilei Fu
- Department of Computer Science, Rice University, Houston, TX, USA
| | | | - Medhat Mahmoud
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | | | - Sissel Juul
- Oxford Nanopore Technologies Inc, New York, NY, USA
| | - Todd J Treangen
- Department of Computer Science, Rice University, Houston, TX, USA.
- Department of Bioengineering, Rice University, Houston, TX, USA.
| | - Fritz J Sedlazeck
- Department of Computer Science, Rice University, Houston, TX, USA.
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA.
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.
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Gallardo-Cóndor J, Naranjo P, Atarihuana S, Coello D, Guevara-Ramírez P, Flores-Espinoza R, Burgos G, López-Cortés A, Cabrera-Andrade A. Population-Specific Distribution of TPMT Deficiency Variants and Ancestry Proportions in Ecuadorian Ethnic Groups: Towards Personalized Medicine. Ther Clin Risk Manag 2023; 19:1005-1018. [PMID: 38050617 PMCID: PMC10693761 DOI: 10.2147/tcrm.s432856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 11/06/2023] [Indexed: 12/06/2023] Open
Abstract
Purpose Thiopurine S-methyltransferase (TPMT) is an enzyme that metabolizes purine analogs, agents used in the treatment of acute lymphoblastic leukemia. Improper drug metabolism leads to toxicity in chemotherapy patients and reduces treatment effectiveness. TPMT variants associated with reduced enzymatic activity vary across populations. Therefore, studying these variants in heterogeneous populations, such as Ecuadorians, can help identify molecular causes of deficiency for this enzyme. Methods We sequenced the entire TPMT coding region in 550 Ecuadorian individuals from Afro-Ecuadorian, Indigenous, Mestizo, and Montubio ethnicities. Moreover, we conducted an ancestry analysis using 46 informative ancestry markers. Results We identified 8 single nucleotide variants in the coding region of TPMT. The most prevalent alleles were TPMT*3A, TPMT*3B, and TPMT*3C, with frequencies of 0.055, 0.012, and 0.015, respectively. Additionally, we found rare alleles TPMT*4 and TPMT*8 with frequencies of 0.005 and 0.003. Correlating the ancestry proportions with TPMT-deficient genotypes, we observed that the Native American ancestry proportion influenced the distribution of the TPMT*1/TPMT*3A genotype (OR = 5.977, p = 0.002), while the contribution of African ancestral populations was associated with the TPMT*1/TPMT*3C genotype (OR = 9.769, p = 0.003). The rates of TPMT-deficient genotypes observed in Mestizo (f = 0.121) and Indigenous (f = 0.273) groups provide evidence for the influence of Native American ancestry and the prevalence of the TPMT*3A allele. In contrast, although Afro-Ecuadorian groups demonstrate similar deficiency rates (f = 0.160), the genetic factors involved are associated with contributions from African ancestral populations, specifically the prevalent TPMT*3C allele. Conclusion The distribution of TPMT-deficient variants offers valuable insights into the populations under study, underscoring the necessity for genetic screening strategies to prevent thiopurine toxicity events among Latin American minority groups.
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Affiliation(s)
| | - Pablo Naranjo
- Facultad de Ingeniería y Ciencias Aplicadas, Universidad de Las Américas, Quito, Ecuador
| | - Sebastián Atarihuana
- Facultad de Ingeniería y Ciencias Aplicadas, Universidad de Las Américas, Quito, Ecuador
| | - Dayana Coello
- Laboratorios de Investigación, Universidad de Las Américas, Quito, Ecuador
| | - Patricia Guevara-Ramírez
- Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador
| | - Rodrigo Flores-Espinoza
- Laboratório de Diagnóstico por DNA (LDD), Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Germán Burgos
- One Health Research Group, Facultad de Medicina, Universidad de Las Américas, Quito, Ecuador
- Grupo de Medicina Xenomica, Instituto de Ciencias Forenses, Universidad de Santiago de Compostela, Satiago de Compostela, Spain
| | - Andrés López-Cortés
- Cancer Research Group (CRG), Faculty of Medicine, Universidad de Las Américas, Quito, Ecuador
- Latin American Network for the Implementation and Validation of Clinical Pharmacogenomics Guidelines (RELIVAF-CYTED), Madrid, Spain
| | - Alejandro Cabrera-Andrade
- Escuela de Enfermería, Facultad de Ciencias de la Salud, Universidad de Las Américas, Quito, Ecuador
- Grupo de Bio-Quimioinformática, Universidad de Las Américas, Quito, Ecuador
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Mora Y, Villegas C, Mora YM, Moreno N. TPMT gene polymorphisms (c.238G>C, c.460G>A and c.719A>G) in a healthy Venezuelan population. Pharmacogenomics 2023; 24:219-225. [PMID: 36946340 DOI: 10.2217/pgs-2022-0187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023] Open
Abstract
Background: The presence of polymorphisms in the TPMT gene is associated with adverse effects in patients treated with standard doses of thiopurine drugs. Scientific evidence recognizes significant ethnic differences in their frequencies and how their early identification can prevent clinical complications. Methods: 150 healthy residents of Aragua, Venezuela were enrolled. The SNPs c.460G>A and c.719A>G were detected by PCR-restriction fragment length polymorphism assay and c.238G>C by allele-specific PCR. Results: All genotype polymorphisms were heterozygous. TPMT*1/*3A, TPMT*1/*3C and TPMT*1/*2 genotypes were found in 4.0, 2.0 and 0.7%, respectively. Conclusion: 6.7% of individuals have an intermediate TPMT activity. These findings support the importance of prior genotyping of TPMT in Venezuelan patients who require thiopurine drug therapy.
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Affiliation(s)
- Yuselin Mora
- Instituto de Investigaciones Biomédicas 'Dr. Francisco J. Triana Alonso' (BIOMED) - Sección de Polimorfismos Genómicos, Facultad de Ciencias de la Salud, Universidad de Carabobo, Sede Aragua, Maracay, 2102, Venezuela
| | - Cecilia Villegas
- Instituto de Investigaciones Biomédicas 'Dr. Francisco J. Triana Alonso' (BIOMED) - Sección de Polimorfismos Genómicos, Facultad de Ciencias de la Salud, Universidad de Carabobo, Sede Aragua, Maracay, 2102, Venezuela
| | - Yamile M Mora
- Instituto de Investigaciones Biomédicas 'Dr. Francisco J. Triana Alonso' (BIOMED) - Sección de Polimorfismos Genómicos, Facultad de Ciencias de la Salud, Universidad de Carabobo, Sede Aragua, Maracay, 2102, Venezuela
| | - Nancy Moreno
- Instituto de Investigaciones Biomédicas 'Dr. Francisco J. Triana Alonso' (BIOMED) - Sección de Polimorfismos Genómicos, Facultad de Ciencias de la Salud, Universidad de Carabobo, Sede Aragua, Maracay, 2102, Venezuela
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Gonzalez-Covarrubias V, Martínez-Martínez E, del Bosque-Plata L. The Potential of Metabolomics in Biomedical Applications. Metabolites 2022; 12:metabo12020194. [PMID: 35208267 PMCID: PMC8880031 DOI: 10.3390/metabo12020194] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/28/2022] [Accepted: 01/30/2022] [Indexed: 12/12/2022] Open
Abstract
The metabolome offers a dynamic, comprehensive, and precise picture of the phenotype. Current high-throughput technologies have allowed the discovery of relevant metabolites that characterize a wide variety of human phenotypes with respect to health, disease, drug monitoring, and even aging. Metabolomics, parallel to genomics, has led to the discovery of biomarkers and has aided in the understanding of a diversity of molecular mechanisms, highlighting its application in precision medicine. This review focuses on the metabolomics that can be applied to improve human health, as well as its trends and impacts in metabolic and neurodegenerative diseases, cancer, longevity, the exposome, liquid biopsy development, and pharmacometabolomics. The identification of distinct metabolomic profiles will help in the discovery and improvement of clinical strategies to treat human disease. In the years to come, metabolomics will become a tool routinely applied to diagnose and monitor health and disease, aging, or drug development. Biomedical applications of metabolomics can already be foreseen to monitor the progression of metabolic diseases, such as obesity and diabetes, using branched-chain amino acids, acylcarnitines, certain phospholipids, and genomics; these can assess disease severity and predict a potential treatment. Future endeavors should focus on determining the applicability and clinical utility of metabolomic-derived markers and their appropriate implementation in large-scale clinical settings.
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Affiliation(s)
| | - Eduardo Martínez-Martínez
- Laboratory of Cell Communication and Extracellular Vesicles, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico;
| | - Laura del Bosque-Plata
- Laboratory of Nutrigenetics and Nutrigenomics, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico
- Correspondence: ; Tel.: +52-55-53-50-1974
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Grover N, Bhatia P, Kumar A, Singh M, Lad D, Mandavdhare HS, Samanta J, Prasad KK, Dutta U, Sharma V. TPMT and NUDT15 polymorphisms in thiopurine induced leucopenia in inflammatory bowel disease: a prospective study from India. BMC Gastroenterol 2021; 21:327. [PMID: 34425754 PMCID: PMC8383411 DOI: 10.1186/s12876-021-01900-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 08/11/2021] [Indexed: 12/24/2022] Open
Abstract
Background Polymorphisms in thiopurine methyltransferase (TPMT) and Nudix hydrolase-15 (NUDT15) have been implicated as the predominant cause of thiopurine induced leukopenia in the Western countries and East Asia respectively. Exact role of these polymorphisms in South Asian population with inflammatory bowel disease (IBD) is uncertain. Methods We included consecutive patients with IBD who were initiated on thiopurines at a center in North India. The dosage of thiopurines was titrated using regular monitoring of hemogram and liver function tests. Three TPMT polymorphisms (c.238 G > C, c.460 G > A, and c.719A > G) and one NUDT15 polymorphism (c.415 C > T) were assessed. Comparison regarding incidence of leukopenia and maximum tolerated thiopurine dosage was performed between those with wild polymorphism and those with TPMT and NUDT15 polymorphisms, respectively. Results Of the 119 patients (61 males, mean age 36.8 ± 13.5 years), 105 (88.2%) had ulcerative colitis and 14 (11.8%) had Crohn’s disease. Leukopenia was noted in 33 (27.7%), gastrointestinal intolerance in 5 (4.2%) and pancreatitis in 2 (1.6%). TPMT polymorphisms were detected amongst five patients of whom 1 developed leukopenia. NUDT15 polymorphism was noted in 13 patients of whom 7 had leukopenia. The odds of developing leukopenia in TPMT polymorphism were non-significant (0.77, 95% CI:0.0822 to 7.2134, P = 0.819) but were significantly higher in those with NUDT15 polymorphism (3.5933, 1.1041 to 11.6951, P value: = 0.0336). Conclusion NUDT15 polymorphism was more frequent than TPMT polymorphisms and was associated with thiopurine induced leukopenia. However, the tested polymorphisms account for only 24.2% of the risk of thiopurine induced leukopenia. Supplementary Information The online version contains supplementary material available at 10.1186/s12876-021-01900-8.
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Affiliation(s)
- Narinder Grover
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Prateek Bhatia
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Antriksh Kumar
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Minu Singh
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Deepesh Lad
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Harshal S Mandavdhare
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Jayanta Samanta
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Kaushal K Prasad
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Usha Dutta
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Vishal Sharma
- Department of Internal Medicine, Pediatric Hemato-Oncology, Gastroenterology and Hematology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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TPMT*3C as a Predictor of 6-Mercaptopurine-Induced Myelotoxicity in Thai Children with Acute Lymphoblastic Leukemia. J Pers Med 2021; 11:jpm11080783. [PMID: 34442427 PMCID: PMC8400562 DOI: 10.3390/jpm11080783] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/05/2021] [Accepted: 08/09/2021] [Indexed: 01/16/2023] Open
Abstract
The response to 6-mercaptopurine (6-MP) can be altered by genetic polymorphisms in genes encoding drug-metabolizing enzymes and drug transporters. The purpose of this study was to investigate the association between genetic polymorphisms of drug-metabolizing enzymes (TPMT 719A > G (*3C), ITPA 94C > A and ITPA 123G > A) and drug transporters (MRP4 912C > A and MRP4 2269G > A) with 6-MP-related myelotoxicity and hepatotoxicity in Thai children with acute lymphoblastic leukemia (ALL). The prescribed dosage of 6-MP and its adverse effects were assessed from medical records during the first 8 weeks and 9–24 weeks of maintenance therapy. Children with the TPMT*1/*3C genotype had a higher risk of leukopenia with an odds ratio (OR) of 4.10 (95% confidence interval (CI) of 1.06–15.94; p = 0.033) compared to wild type (TPMT*1/*1) patients. Heterozygous TPMT*3C was significantly associated with severe neutropenia with an increased risk (OR, 4.17; 95% CI, 1.25–13.90); p = 0.014) during the first 8 weeks. No association was found among ITPA94C > A, ITPA123G > A, MRP4 912C > A, and MRP4 2269G > A with myelotoxicity and hepatotoxicity. The evidence that TPMT heterozygotes confer risks of 6-MP-induced myelotoxicity also supports the convincing need to genotype this pharmacogenetic marker before the initiation of 6-MP therapy.
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Russell LE, Zhou Y, Almousa AA, Sodhi JK, Nwabufo CK, Lauschke VM. Pharmacogenomics in the era of next generation sequencing - from byte to bedside. Drug Metab Rev 2021; 53:253-278. [PMID: 33820459 DOI: 10.1080/03602532.2021.1909613] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Pharmacogenetic research has resulted in the identification of a multitude of genetic variants that impact drug response or toxicity. These polymorphisms are mostly common and have been included as actionable information in the labels of numerous drugs. In addition to common variants, recent advances in Next Generation Sequencing (NGS) technologies have resulted in the identification of a plethora of rare and population-specific pharmacogenetic variations with unclear functional consequences that are not accessible by conventional forward genetics strategies. In this review, we discuss how comprehensive sequencing information can be translated into personalized pharmacogenomic advice in the age of NGS. Specifically, we provide an update of the functional impacts of rare pharmacogenetic variability and how this information can be leveraged to improve pharmacogenetic guidance. Furthermore, we critically discuss the current status of implementation of pharmacogenetic testing across drug development and layers of care. We identify major gaps and provide perspectives on how these can be minimized to optimize the utilization of NGS data for personalized clinical decision-support.
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Affiliation(s)
| | - Yitian Zhou
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Ahmed A Almousa
- Department of Pharmacy, London Health Sciences Center, Victoria Hospital, London, ON, Canada
| | - Jasleen K Sodhi
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA, USA.,Department of Drug Metabolism and Pharmacokinetics, Plexxikon, Inc., Berkeley, CA, USA
| | | | - Volker M Lauschke
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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Mohammad RA. Part I: Inflammatory bowel disease. JOURNAL OF THE AMERICAN COLLEGE OF CLINICAL PHARMACY 2020. [DOI: 10.1002/jac5.1347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Chang WC, Tanoshima R, Ross CJD, Carleton BC. Challenges and Opportunities in Implementing Pharmacogenetic Testing in Clinical Settings. Annu Rev Pharmacol Toxicol 2020; 61:65-84. [PMID: 33006916 DOI: 10.1146/annurev-pharmtox-030920-025745] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The clinical implementation of pharmacogenetic biomarkers continues to grow as new genetic variants associated with drug outcomes are discovered and validated. The number of drug labels that contain pharmacogenetic information also continues to expand. Published, peer-reviewed clinical practice guidelines have also been developed to support the implementation of pharmacogenetic tests. Incorporating pharmacogenetic information into health care benefits patients as well as clinicians by improving drug safety and reducing empiricism in drug selection. Barriers to the implementation of pharmacogenetic testing remain. This review explores current pharmacogenetic implementation initiatives with a focus on the challenges of pharmacogenetic implementation and potential opportunities to overcome these challenges.
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Affiliation(s)
- Wan-Chun Chang
- Division of Translational Therapeutics, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia V6H 3V4, Canada; .,BC Children's Hospital Research Institute, Vancouver, British Columbia V5Z 4H4, Canada
| | - Reo Tanoshima
- Division of Translational Therapeutics, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia V6H 3V4, Canada; .,BC Children's Hospital Research Institute, Vancouver, British Columbia V5Z 4H4, Canada
| | - Colin J D Ross
- BC Children's Hospital Research Institute, Vancouver, British Columbia V5Z 4H4, Canada.,Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Bruce C Carleton
- Division of Translational Therapeutics, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia V6H 3V4, Canada; .,BC Children's Hospital Research Institute, Vancouver, British Columbia V5Z 4H4, Canada.,Pharmaceutical Outcomes Programme, BC Children's Hospital Research Institute, Vancouver, British Columbia V5Z 4H4, Canada
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King C, McKenna A, Farzan N, Vijverberg SJ, van der Schee MP, Maitland-van der Zee AH, Arianto L, Bisgaard H, BØnnelykke K, Berce V, PotoČnik U, Repnik K, Carleton B, Daley D, Chew FT, Chiang WC, Sio YY, Cloutier MM, Den Dekker HT, Duijts L, de Jongste JC, Dijk FN, Flores C, Hernandez-Pacheco N, Mukhopadhyay S, Basu K, Tantisira KG, Verhamme KM, Celedón JC, Forno E, Canino G, Francis B, Pirmohamed M, Sinha I, Hawcutt DB. Pharmacogenomic associations of adverse drug reactions in asthma: systematic review and research prioritisation. THE PHARMACOGENOMICS JOURNAL 2020; 20:621-628. [PMID: 31949291 PMCID: PMC7502355 DOI: 10.1038/s41397-019-0140-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 11/22/2019] [Accepted: 12/16/2019] [Indexed: 11/16/2022]
Abstract
A systematic review of pharmacogenomic studies capturing adverse drug reactions (ADRs) related to asthma medications was undertaken, and a survey of Pharmacogenomics in Childhood Asthma (PiCA) consortia members was conducted. Studies were eligible if genetic polymorphisms were compared with suspected ADR(s) in a patient with asthma, as either a primary or secondary outcome. Five studies met the inclusion criteria. The ADRs and polymorphisms identified were change in lung function tests (rs1042713), adrenal suppression (rs591118), and decreased bone mineral density (rs6461639) and accretion (rs9896933, rs2074439). Two of these polymorphisms were replicated within the paper, but none had external replication. Priorities from PiCA consortia members (representing 15 institution in eight countries) for future studies were tachycardia (SABA/LABA), adrenal suppression/crisis and growth suppression (corticosteroids), sleep/behaviour disturbances (leukotriene receptor antagonists), and nausea and vomiting (theophylline). Future pharmacogenomic studies in asthma should collect relevant ADR data as well as markers of efficacy.
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Affiliation(s)
- Charlotte King
- Department of Women and Child's Health, Institute of Translational Medicine, University of Liverpool, Liverpool, England
| | - Amanda McKenna
- Department of Women and Child's Health, Institute of Translational Medicine, University of Liverpool, Liverpool, England
| | - Niloufar Farzan
- Department of Respiratory Medicine, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands
| | - Susanne J Vijverberg
- Department of Respiratory Medicine, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands
| | - Marc P van der Schee
- Department of Respiratory Medicine, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands
| | - Anke H Maitland-van der Zee
- Department of Respiratory Medicine, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands
| | - Lambang Arianto
- Copenhagen Prospective Studies on Asthma in Childhood, Herlev & Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Hans Bisgaard
- Copenhagen Prospective Studies on Asthma in Childhood, Herlev & Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Klaus BØnnelykke
- Copenhagen Prospective Studies on Asthma in Childhood, Herlev & Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Vojko Berce
- Department of Pediatrics, University Medical Centre Maribor, Maribor, Slovenia
- Centre for Human Molecular Genetics & Pharmacogenomics, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Uros PotoČnik
- Centre for Human Molecular Genetics & Pharmacogenomics, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Katja Repnik
- Centre for Human Molecular Genetics & Pharmacogenomics, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Bruce Carleton
- Division of Translational Therapeutics, Department of Pediatrics, Faculty of Medicine, University of British Columbia, BC Children's Hospital and Research Institute, Vancouver, Canada
| | - Denise Daley
- Division of Translational Therapeutics, Department of Pediatrics, Faculty of Medicine, University of British Columbia, BC Children's Hospital and Research Institute, Vancouver, Canada
| | - Fook Tim Chew
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Allergy & Immunology Division, Department of Paediatric Medicine, KK Children's Hospital, Singapore, Singapore
| | - Wen Chin Chiang
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Allergy & Immunology Division, Department of Paediatric Medicine, KK Children's Hospital, Singapore, Singapore
| | - Yang Yie Sio
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Allergy & Immunology Division, Department of Paediatric Medicine, KK Children's Hospital, Singapore, Singapore
| | - Michelle M Cloutier
- Asthma Center, Connecticut Children's Medical Center, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Herman T Den Dekker
- Department of Pediatrics, Division of Respiratory Medicine & Allergology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Liesbeth Duijts
- Department of Pediatrics, Division of Respiratory Medicine & Allergology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Johan C de Jongste
- Department of Pediatric Pulmonology & Pediatric Allergology, University Medical Center Groningen, University of Groningen, Beatrix Children's Hospital, Groningen, The Netherlands
| | - F Nicole Dijk
- Department of Pediatric Pulmonology & Pediatric Allergology, University Medical Center Groningen, University of Groningen, Beatrix Children's Hospital, Groningen, The Netherlands
- Groningen Research Institute for Asthma & COPD, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Carlos Flores
- Research Unit, Hospital Universitario N.S. de Candelaria, Universidad de La Laguna, Santa Cruz de Tenerife, Spain
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- Genomics Division, Instituto Tecnológico y de Energías Renovables (ITER), Santa Cruz de Tenerife, Spain
| | - Natalia Hernandez-Pacheco
- Research Unit, Hospital Universitario N.S. de Candelaria, Universidad de La Laguna, Santa Cruz de Tenerife, Spain
- Genomics and Health Group, Department of Biochemistry, Microbiology, Cell Biology and Genetics, Universidad de La Laguna, San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain
| | - Somnath Mukhopadhyay
- Academic Department of Paediatrics, Brighton & Sussex Medical School, Royal Alexandra Children's Hospital, Brighton, UK
| | - Kaninika Basu
- Academic Department of Paediatrics, Brighton & Sussex Medical School, Royal Alexandra Children's Hospital, Brighton, UK
| | - Kelan G Tantisira
- The Channing Division of Network Medicine, Department of Medicine, Boston, MA, 02115, USA
- Division of Pulmonary & Critical Care Medicine, Brigham & Women's Hospital & Harvard Medical School, Boston, MA, 02115, USA
| | - Katia M Verhamme
- Department of Medical Informatics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Juan C Celedón
- Division of Pediatric Pulmonary Medicine, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, USA
| | - Erick Forno
- Division of Pediatric Pulmonary Medicine, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, USA
| | - Glorisa Canino
- Behavioral Sciences Research Institute, University of Puerto Rico, San Juan, Puerto Rico
| | - Ben Francis
- Department of Biostatistics, Institute of Translational Medicine, University of Liverpool, Liverpool, England
| | - Munir Pirmohamed
- Department of Molecular & Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, England
| | - Ian Sinha
- Department of Respiratory Medicine, Alder Hey Children's Hospital, Liverpool, England
| | - Daniel B Hawcutt
- Department of Women and Child's Health, Institute of Translational Medicine, University of Liverpool, Liverpool, England.
- NIHR Alder Hey Clinical Research Facility, Alder Hey Children's Hospital, Liverpool, England.
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11
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Mokhtari M, Mostanbet F, Nekooee Fard S, Shekarkhar G, Sepaskhah M, Sadati MS. Thiopurine S-methyltransferase and Pemphigus Vulgaris: A Phenotype-Genotype Study. IRANIAN JOURNAL OF PATHOLOGY 2020; 15:299-305. [PMID: 32944042 PMCID: PMC7477690 DOI: 10.30699/ijp.2020.121365.2320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/10/2020] [Indexed: 11/22/2022]
Abstract
Background & Objective: Thiopurine drugs are considered as a treatment modality in various autoimmune disorders including pemphigus vulgaris (PV). These drugs are metabolized by an enzyme “Thiopurine S-methyl transferase” (TPMT). Various variants of this enzyme may have decreased activity leading to serious drug side effects. To investigate the phenotype and genotype of TPMT in PV patients receiving thiopurine drugs. Methods: A total of 50 patients (29 women and 21 men) with pemphigus vulgaris treating with standard dose of Thiopurine drugs were selected. Sex, age, result of liver function test and complete blood count were recorded. Genotyping of two common non-functional allele (TPMT*2 and TPMT*3C) by Allele-specific and RFLP-PCR was performed. TPMT enzymatic level was determined by an ELISA based method. Results: Of patients, 36 (72%) were found to have normal TPMT level; and 12, (24%) had higher level of enzyme and 2, 4% had low TPMT enzyme, but none of the patients showed mutant TPMT*2 and TPMT*3C alleles. None of the patients showed hepatotoxicity and bone marrow suppression. Conclusion: The phenotypic assay based on ELISA method may have false positive and misleading results but genotyping using PCR-RFLP and allele specific PCR is accurate, simple and cost-effective and can be used in patients decided to undergo thiopurine treatment.
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Affiliation(s)
- Maral Mokhtari
- Pathology Department, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Farzaneh Mostanbet
- Pathology Department, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Saideh Nekooee Fard
- Pathology Department, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Golsa Shekarkhar
- Pathology Department, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mozhdeh Sepaskhah
- Dermatology Department, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Maryam Sadat Sadati
- Dermatology Department, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
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12
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Yao P, Qu XM, Ren S, Ren XD, Su N, Zhao N, Wang L, Cheng L, Weng BB, Sun FJ, Huang Q. Scorpion primer PCR analysis for genotyping of allele variants of thiopurine s‑methyltransferase*3. Mol Med Rep 2020; 22:1994-2002. [PMID: 32705177 PMCID: PMC7411393 DOI: 10.3892/mmr.2020.11283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 05/27/2020] [Indexed: 11/09/2022] Open
Abstract
Thiopurine S-methyltransferase (TPMT) plays an important role in the metabolism of thiopurines. Mutations in the TPMT gene can affect drug activity, which may have adverse effects in humans. Thus, genotyping can help elucidate genetic determinants of drug response to thiopurines and optimize the selection of drug therapies for individual patients, effectively avoiding palindromia during maintenance treatment caused by insufficient dosing and the serious side effects caused by excessive doses. The current available detection methods used for TPMT*3B and TPMT*3C are complex, costly and time-consuming. Therefore, innovative detection methods for TPMT genotyping are urgently required. The aim of the present study was to establish and optimize a simple, specific and timesaving TPMT genotyping method. Using the principles of Web-based Allele-Specific PCR and competitive real-time fluorescent allele-specific PCR (CRAS-PCR), two pairs of Scorpion primers were designed for the detection of TPMT*3B and *3C, respectively, and a mutation in TPMT*3A was inferred based on data from TPMT*3B and *3C. In total, 226 samples from volunteers living in Chongqing were used for CRAS-PCR to detect TPMT*3 mutations. Results showed that nine (3.98%) were mutant (MT) heterozygotes and none were MT homozygotes for TPMT*3C, and no TPMT*3A and TPMT*3B mutations were found. Three TPMT*3C MT heterozygotes were randomly selected for DNA sequencing, and CRAS-PCR results were consistent with the sequencing results. In conclusion, in order to improve simplicity, specificity and efficiency, the present study established and optimized CRAS-PCR assays for commonly found mutant alleles of TPMT*3A (G460A and A719G), TPMT*3B (G460A), and TPMT*3C (A719G).
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Affiliation(s)
- Pu Yao
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing 400042, P.R. China
| | - Xue-Mei Qu
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing 400042, P.R. China
| | - Sai Ren
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing 400042, P.R. China
| | - Xiao-Dong Ren
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing 400042, P.R. China
| | - Ning Su
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing 400042, P.R. China
| | - Na Zhao
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Liu Wang
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing 400042, P.R. China
| | - Lin Cheng
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Bang-Bi Weng
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Feng-Jun Sun
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Qing Huang
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University (Army Medical University), Chongqing 400042, P.R. China
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13
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Root A, Johnson R, McGee A, Lee HJ, Yang S, Voora D. Understanding the state of pharmacogenomic testing for thiopurine methyltransferase within a large health system. Pharmacogenomics 2020; 21:411-418. [DOI: 10.2217/pgs-2019-0148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To investigate the current state of TPMT testing at a single-academic medical center. Methods: Single-center, retrospective chart review for patients newly prescribed a thiopurine. Data collection and evaluation included the prevalence and timing of TPMT testing, correct dosage adjustment if applicable, and incidence of myelosuppression. Results: 121 patients (71%) received TPMT testing. Out of the tested patients, 110 (90.9%) were designated as wild-type with normal metabolism. Dosing modification was appropriate in applicable patients. In unadjusted analysis, there was a lower incidence of myelosuppression among patients who were tested versus those who were not (16.5 vs 36.7%). Conclusion: Based on the study results, TPMT testing opportunities exist for nearly 30% of patients. Testing may reduce the incidence of myelosuppression.
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Affiliation(s)
- Adam Root
- Department of Pharmacy, Duke University Hospital, Durham, NC 27710, USA
| | - Randall Johnson
- Department of Pharmacy, Duke University Hospital, Durham, NC 27710, USA
| | - Ann McGee
- Department of Pharmacy, Duke University Hospital, Durham, NC 27710, USA
| | - Hui-Jie Lee
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC 27705, USA
| | - Siyun Yang
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC 27705, USA
| | - Deepak Voora
- Duke Center for Applied Genomics & Precision Medicine, Duke University School of Medicine, Durham, NC 27708, USA
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14
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Influence of TPMT polymorphisms on azathioprine-induced myelosuppression in Bangladeshi patients with systemic lupus erythematosus. DRUGS & THERAPY PERSPECTIVES 2020. [DOI: 10.1007/s40267-020-00716-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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15
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Berends SE, Strik AS, Löwenberg M, D'Haens GR, Mathôt RAA. Clinical Pharmacokinetic and Pharmacodynamic Considerations in the Treatment of Ulcerative Colitis. Clin Pharmacokinet 2020; 58:15-37. [PMID: 29752633 PMCID: PMC6326086 DOI: 10.1007/s40262-018-0676-z] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) of unknown etiology, probably caused by a combination of genetic and environmental factors. The treatment of patients with active UC depends on the severity, localization and history of IBD medication. According to the classic step-up approach, treatment with 5-aminosalicylic acid compounds is the first step in the treatment of mild to moderately active UC. Corticosteroids, such as prednisolone are used in UC patients with moderate to severe disease activity, but only for remission induction therapy because of side effects associated with long-term use. Thiopurines are the next step in the treatment of active UC but monotherapy during induction therapy in UC patients is not preferred because of their slow onset. Therapeutic drug monitoring (TDM) of the pharmacologically active metabolites of thiopurines, 6-thioguanine nucleotide (6-TGN), has proven to be beneficial. Thiopurine S-methyltransferase (TMPT) plays a role in the metabolic conversion pathway of thiopurines and exhibits genetic polymorphism; however, the clinical benefit and relevance of TPMT genotyping is not well established. In patients with severely active UC refractory to corticosteroids, calcineurin inhibitors such as ciclosporin A (CsA) and tacrolimus are potential therapeutic options. These agents usually have a rather rapid onset of action. Monoclonal antibodies (anti-tumor necrosis factor [TNF] agents, vedolizumab) are the last pharmacotherapeutic option for UC patients before surgery becomes inevitable. Body weight, albumin status and antidrug antibodies contribute to the variability in the pharmacokinetics of anti-TNF agents. Additionally, the use of concomitant immunomodulators (thiopurines/methotrexate) lowers the rate of immunogenicity, and therefore the concomitant use of anti-TNF therapy with an immunomodulator may confer some advantage compared with monotherapy in certain patients. TDM of anti-TNF agents could be beneficial in patients with primary nonresponse and secondary loss of response. The potential benefit of applying TDM during vedolizumab treatment has yet to be determined.
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Affiliation(s)
- Sophie E Berends
- Department Hospital Pharmacy, Academic Medical Center, Amsterdam, The Netherlands.
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands.
| | - Anne S Strik
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Mark Löwenberg
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Geert R D'Haens
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Ron A A Mathôt
- Department Hospital Pharmacy, Academic Medical Center, Amsterdam, The Netherlands
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16
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Karppinen S, Lohi O, Vihola M. Prediction of leukocyte counts during paediatric acute lymphoblastic leukaemia maintenance therapy. Sci Rep 2019; 9:18076. [PMID: 31792398 PMCID: PMC6889389 DOI: 10.1038/s41598-019-54492-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 11/12/2019] [Indexed: 12/29/2022] Open
Abstract
Maintenance chemotherapy with oral 6-mercaptopurine and methotrexate remains a cornerstone of modern therapy for acute lymphoblastic leukaemia. The dosage and intensity of therapy are based on surrogate markers such as peripheral blood leukocyte and neutrophil counts. Dosage based leukocyte count predictions could provide support for dosage decisions clinicians face trying to find and maintain an appropriate dosage for the individual patient. We present two Bayesian nonlinear state space models for predicting patient leukocyte counts during the maintenance therapy. The models simplify some aspects of previously proposed models but allow for some extra flexibility. Our second model is an extension which accounts for extra variation in the leukocyte count due to a treatment adversity, infections, using C-reactive protein as a surrogate. The predictive performances of our models are compared against a model from the literature using time series cross-validation with patient data. In our experiments, our simplified models appear more robust and deliver competitive results with the model from the literature.
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Affiliation(s)
- Santeri Karppinen
- University of Jyväskylä, Department of Mathematics and Statistics, Jyväskylä, FI-40014, Finland.
| | - Olli Lohi
- Tampere Center for Child Health Research, Faculty of Medicine and Health Technology, Tampere University and Tampere University Hospital, Tampere, FI-33521, Finland
| | - Matti Vihola
- University of Jyväskylä, Department of Mathematics and Statistics, Jyväskylä, FI-40014, Finland
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17
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Abstract
Precision medicine was conceptualized on the strength of genomic sequence analysis. High-throughput functional metrics have enhanced sequence interpretation and clinical precision. These technologies include metabolomics, magnetic resonance imaging, and I rhythm (cardiac monitoring), among others. These technologies are discussed and placed in clinical context for the medical specialties of internal medicine, pediatrics, obstetrics, and gynecology. Publications in these fields support the concept of a higher level of precision in identifying disease risk. Precise disease risk identification has the potential to enable intervention with greater specificity, resulting in disease prevention-an important goal of precision medicine.
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Affiliation(s)
- Thomas Caskey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030;
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18
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Bolaji OO, Adehin A, Adeagbo BA. Pharmacogenomics in the Nigerian population: the past, the present and the future. Pharmacogenomics 2019; 20:915-926. [DOI: 10.2217/pgs-2019-0046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The Nigerian population exhibits huge ethnic and genetic diversity, typical of African populations, which can be harnessed for improved drug-response and disease management. Existing data on genes relevant to drug response, so far generated for the population, indeed confirm the prevalence of some clinically significant pharmacogenes. These reports detail prevailing genetic alleles and metabolic phenotypes of vital drug metabolizing monooxygenases, transferases and drug transporters. While the utilization of existing pharmacogenomic data for healthcare delivery remains unpopular, several past and on-going studies suggest that a future shift toward genotype-stratified dosing of drugs and disease management in the population is imminent. This review discusses the present state of pharmacogenomics in Nigeria and the potential benefits of sustained research in this field for the population.
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Affiliation(s)
- Oluseye O Bolaji
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Nigeria
| | - Ayorinde Adehin
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Nigeria
- Institute of Biomedical & Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, PR China
| | - Babatunde A Adeagbo
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Nigeria
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19
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Qu XM, Zhao N, Mo QY, Yao P, Su N, Wei K, Wang L, Huang JF, Ren XD, Ren S, Fu WL, Huang Q. Development of duplex-crossed allele-specific PCR targeting of TPMT*3B and *3C using crossed allele-specific blockers to eliminate non-specific amplification. Anal Biochem 2019; 575:54-62. [PMID: 30935835 DOI: 10.1016/j.ab.2019.03.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 12/18/2022]
Abstract
Prospective testing for variants in the thiopurine S-methyltransferase (TPMT) is considered a key process in the development of thiopurine therapy. This testing is done to avoid toxicity and side effects in the management of diverse immunological and malignant conditions. Real-time fluorescent PCR techniques using duplex-crossed allele-specific primers in a single tube (DCAS-PCR) were developed in this study to genotype the common loss-of-function TPMT*3B c.460G > A (rs1800460) and TPMT*3C c.719A > G (rs1142345) usually occurring in individuals of Chinese ethnicity. In this method, several integrated strategies were used to completely eliminate the non-specific amplification that is commonly presented in traditional allele-specific (AS) PCR. These strategies include using AS-primers (ASP) that both are artificially mismatched in the penultimate positions and phosphorothioate modifications in the 5'-termini positions. In the assay, an AS-blocker was used, locus-specific TaqMan (LST) probes were used and we used at least two fragments were simultaneously amplified in a single tube which satisfy the thermodynamic characteristics of DNA polymerase to eliminate non-specific amplification. In a group of 200 unselected subjects, the results showed that 8 samples were heterozygous of TPMT*3C, and all samples possessed wild-type TPMT*3B. There was no non-specific amplification, and the genotypes were 100% consistent with Sanger sequencing.
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Affiliation(s)
- Xue-Mei Qu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China; Department of Laboratory Medicine, Daping Hospital, Third Military Medical University(Army Medical University), Chongqing, 400042, PR China
| | - Na Zhao
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China
| | - Qin-Yun Mo
- Department of Transfusion Medicine, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, PR China
| | - Pu Yao
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China
| | - Ning Su
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China
| | - Kun Wei
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China
| | - Liu Wang
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University(Army Medical University), Chongqing, 400042, PR China
| | - Jun-Fu Huang
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China
| | - Xiao-Dong Ren
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University(Army Medical University), Chongqing, 400042, PR China
| | - Sai Ren
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University(Army Medical University), Chongqing, 400042, PR China
| | - Wei-Ling Fu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China
| | - Qing Huang
- Department of Laboratory Medicine, Daping Hospital, Third Military Medical University(Army Medical University), Chongqing, 400042, PR China; Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University(Army Medical University), Chongqing, 400038, PR China.
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20
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Wang TR, Qiao YQ, Zou DW, Ran ZH. A single-center experience with methotrexate in the treatment of Chinese Crohn's disease patients. J Dig Dis 2018; 19:753-758. [PMID: 30516330 DOI: 10.1111/1751-2980.12694] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/13/2018] [Accepted: 03/13/2018] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Methotrexate (MTX) can be used as an alternative for patients with Crohn's disease (CD) who are intolerant of thiopurine. This retrospective study aimed to provide some clues about MTX treatment in Chinese patients with CD. METHODS Medical records of 27 adult patients with CD who were treated with MTX between 2012 and 2017 at Renji Hospital were reviewed. MTX was administered at 15 mg or 20 mg intramuscularly once per week. The remission and response rates and adverse reactions of MTX were recorded and analyzed. RESULTS Thirteen (48.1%) of the patients achieved remission for more than 12 months, whereas four (14.8%) responded clinically. Eight (29.6%) patients discontinued MTX due to adverse events. The mean age of those who maintained remission was significantly younger than that of those who did not ([35.62 ± 10.99] years vs. [45.43 ± 11.93] years, P < 0.05). The pretreatment C-reactive protein (CRP) level was higher in the group who maintained remission than that in those who did not ([17.20 ± 17.26] mg/L vs. [6.98 ± 5.66] mg/L, P < 0.05). CONCLUSIONS MTX is effective and relatively safe for patients at doses of 15 mg/week or 20 mg/week and may be an alternative therapy for patients who are intolerant of thiopurine. Elderly patients with CD and patients with normal pretreatment CRP level may have a reduced response to MTX.
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Affiliation(s)
- Tian Rong Wang
- Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Yu Qi Qiao
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Duo Wu Zou
- Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Zhi Hua Ran
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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21
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Thomford NE, Dzobo K, Chimusa E, Andrae-Marobela K, Chirikure S, Wonkam A, Dandara C. Personalized Herbal Medicine? A Roadmap for Convergence of Herbal and Precision Medicine Biomarker Innovations. ACTA ACUST UNITED AC 2018; 22:375-391. [DOI: 10.1089/omi.2018.0074] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Nicholas Ekow Thomford
- Pharmacogenomics and Drug Metabolism Research Group, Division of Human Genetics, Department of Pathology and Institute for Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- School of Medical Sciences, University of Cape Coast, Cape Coast, PMB, Ghana
| | - Kevin Dzobo
- International Centre for Genetic Engineering and Biotechnology, Cape Town component, University of Cape Town, Cape Town, South Africa
- Department of Integrative Biomedical Science, Division of Medical Biochemistry, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Emile Chimusa
- Pharmacogenomics and Drug Metabolism Research Group, Division of Human Genetics, Department of Pathology and Institute for Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Kerstin Andrae-Marobela
- Molecular Cell Biology, Department of Biological Sciences, University of Botswana, Gaborone, Botswana
| | - Shadreck Chirikure
- Department of Archaeology, University of Cape Town, Cape Town, South Africa
| | - Ambroise Wonkam
- Pharmacogenomics and Drug Metabolism Research Group, Division of Human Genetics, Department of Pathology and Institute for Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Collet Dandara
- Pharmacogenomics and Drug Metabolism Research Group, Division of Human Genetics, Department of Pathology and Institute for Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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22
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de Boer NKH, Peyrin-Biroulet L, Jharap B, Sanderson JD, Meijer B, Atreya I, Barclay ML, Colombel JF, Lopez A, Beaugerie L, Marinaki AM, van Bodegraven AA, Neurath MF. Thiopurines in Inflammatory Bowel Disease: New Findings and Perspectives. J Crohns Colitis 2018; 12:610-620. [PMID: 29293971 DOI: 10.1093/ecco-jcc/jjx181] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 12/20/2017] [Indexed: 02/08/2023]
Abstract
Thiopurines, available as azathioprine, mercaptopurine, and thioguanine, are immunomodulating agents primarily used to maintain corticosteroid-free remission in patients with inflammatory bowel disease. To provide a state-of-the-art overview of thiopurine treatment in inflammatory bowel disease, this clinical review critically summarises the available literature, as assessed by several experts in the field of thiopurine treatment and research in inflammatory bowel disease.
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Affiliation(s)
- Nanne K H de Boer
- Department of Gastroenterology and Hepatology, VU University Medical Centre, Amsterdam, The Netherlands
| | - Laurent Peyrin-Biroulet
- Department of Gastroenterology and Hepatology and Inserm U954, Nancy University Hospital, Lorraine University, Vandoeuvre-lès-Nancy, France
| | - Bindia Jharap
- Department of Gastroenterology, Meander Medical Centre, Amersfoort, The Netherlands
| | - Jeremy D Sanderson
- Department of Gastroenterology, Guy's and St Thomas' Hospitals, London, UK
| | - Berrie Meijer
- Department of Gastroenterology and Hepatology, VU University Medical Centre, Amsterdam, The Netherlands
| | - Imke Atreya
- Department of Gastroenterology, Pneumology and Endocrinology, Universitätsklinikum Erlangen, University of Erlangen-Nürnberg, Germany
| | - Murray L Barclay
- Department of Gastroenterology, Christchurch Hospital, Christchurch, New Zealand
| | | | - Anthony Lopez
- Department of Gastroenterology and Hepatology and Inserm U954, Nancy University Hospital, Lorraine University, Vandoeuvre-lès-Nancy, France
| | - Laurent Beaugerie
- Department of Gastroenterology, AP-HP, Hôpital Saint-Antoine,UPMC University, Paris, France
| | | | - Adriaan A van Bodegraven
- Department of Gastroenterology and Hepatology, VU University Medical Centre, Amsterdam, The Netherlands.,Department of Gastroenterology, Geriatrics, Internal and Intensive Care Medicine [Co-MIK], Zuyderland Medical Centre, Heerlen-Sittard-Geleen, The Netherlands
| | - Markus F Neurath
- Department of Gastroenterology, Pneumology and Endocrinology, Universitätsklinikum Erlangen, University of Erlangen-Nürnberg, Germany
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23
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Green DJ, Duong SQ, Burckart GJ, Sissung T, Price DK, Figg WD, Brooks MM, Chinnock R, Canter C, Addonizio L, Bernstein D, Naftel DC, Zeevi A, Kirklin JK, Webber SA, Feingold B. Association Between Thiopurine S-Methyltransferase ( TPMT) Genetic Variants and Infection in Pediatric Heart Transplant Recipients Treated With Azathioprine: A Multi-Institutional Analysis. J Pediatr Pharmacol Ther 2018; 23:106-110. [PMID: 29720911 DOI: 10.5863/1551-6776-23.2.106] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVES Bone marrow suppression is a common adverse effect of the immunosuppressive drug azathioprine. Polymorphisms in the gene encoding thiopurine S-methyltransferase (TPMT) can alter the metabolism of azathioprine, resulting in marrow toxicity and life-threatening infection. In a multicenter cohort of pediatric heart transplant (HT) recipients, we determined the frequency of TPMT genetic variation and assessed whether azathioprine-treated recipients with TPMT variants were at increased risk of infection. METHODS We genotyped TPMT in 264 pediatric HT recipients for the presence of the TPMT*2, TPMT*3A, and TPMT*3C variant alleles. Data on infection episodes and azathioprine use were collected as part of each patient's participation in the Pediatric Heart Transplant Study. We performed unadjusted Kaplan-Meier analyses comparing infection outcomes between groups. RESULTS TPMT variants were identified in 26 pediatric HT recipients (10%): *3A (n = 17), *3C (n = 8), and *2 (n = 1). Among those with a variant allele, *3C was most prevalent in black patients (4 of 5) and *3A most prevalent among white and Hispanic patients (16 of 20). Among 175 recipients (66%) who received azathioprine as part of the initial immunosuppressive regimen, we found no difference in the number of infections at 1 year after HT (0.7 ± 1.3; range, 0-6 versus 0.5 ± 0.9; range, 0-3; p = 0.60) or in freedom from infection and bacterial infection between non-variant and variant carriers. There was 1 infection-related death in each group. CONCLUSIONS In this multicenter cohort of pediatric HT recipients, the prevalence of TPMT variants was similar across racial/ethnic groups to what has been previously reported in non-pediatric HT populations. We found no association between variant alleles and infection in the first year after HT. Because clinically detected cytopenia could have prompted dose adjustment or cessation, we recommend future studies assess the relationship of genotype to leukopenia/neutropenia in the pediatric transplantation population.
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Alsous M, Yousef AM, Abdel Jalil M, Zawiah M, Yacoub S, Momani D, Gharabli A, Omar S, Rihani R. Genetic Polymorphism of Thiopurine S-methyltransferase in Children with Acute Lymphoblastic Leukemia in Jordan. Asian Pac J Cancer Prev 2018; 19:199-205. [PMID: 29373914 PMCID: PMC5844618 DOI: 10.22034/apjcp.2018.19.1.199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background and Aims: It has been demonstrated that homozygote and heterozygote mutant allele carriers for thiopurine S-methyltransferase (TPMT) are at high risk of developing myelosuppression after receiving standard doses of 6-mercaptopurine (6-MP). The aim of this study was to determine the frequency of TPMT deficient alleles in children with acute lymphoblastic leukemia (ALL) in Jordan and to compare it with other ethnic groups. Methods: We included 52 ALL childhood cases from King Hussein Cancer Research Center in Jordan. Genotyping of the rs1800460, rs1800462, and rs1142345 SNPs was performed by polymerase chain reaction (PCR) followed by sequencing. Comparisons were made with historical data for controls and for both volunteers and cases from other middle-eastern countries. Results: Mutant TPMT alleles were present in 3.8% (2/52) of patients. Allelic frequencies were 1.0% for both TPMT*B and TPMT*C. None of the patients were heterozygous or homozygous for TPMT*3A or TPMT *2. We did not find statistically significant differences in the distribution of mutant alleles between Jordan and other middle-eastern countries for both healthy volunteers or ALL patients. Conclusions: The overall frequency of TPMT mutant alleles was low and did not exhibit differences compared to other middle-eastern countries, including Jordanian studies assessing TPMT mutant alleles in healthy volunteers. The current results question the value of TPMT genotyping in the Jordanian population.
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Affiliation(s)
- Mervat Alsous
- Department of Clinical Pharmacy and Therapeutics, Faculty of Pharmacy, Applied Science Private University, Amman, Jordan.
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Ramirez-Florencio M, Jiménez-Morales S, Barbosa-Cobos RE, López-Cano DJ, Ramírez-Bello J. High frequency of mutant thiopurine S-methyltransferase genotypes in Mexican patients with systemic lupus erythematosus and rheumatoid arthritis. Clin Rheumatol 2017; 37:963-970. [PMID: 29264794 DOI: 10.1007/s10067-017-3955-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 11/24/2017] [Accepted: 12/12/2017] [Indexed: 12/20/2022]
Abstract
Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are treated with immunosuppressive purine analogs, 6-mercaptopurine/6-thioguanine/azathiopurine, which are inactivated by thiopurine S-methyltransferase (TPMT). Non-synonymous polymorphisms in TPMT are associated with increased risk of adverse effects in patients treated with thiopurines. This study aimed to determine the frequency of the most common mutant TPMT alleles in Mexican patients with SLE (a prototype autoimmune disease) and RA (one of the most common autoimmune diseases in Mexico). Five hundred fifty-three consecutive patients from Central Mexico with SLE (178) and RA (375) were included. Subjects were genotyped to identify TPMT*2 (rs1800462), TPMT*3A (rs1800460 and rs1142345), TPMT*3B (rs1800460), and TPMT*3C (rs1142345) mutant alleles. DNA samples were assayed with the 5' exonuclease technique and TaqMan probes. Mutant alleles were detected in 6.2 and 5.2% of SLE and RA cases, respectively. Of note, 12.4% of SLE cases and 10.1% of RA cases carried mutant genotypes. Among those, the null genotype (TPMT*2/*3A, 0.3%) and the TPMT*3B (0.5%) and TPMT*3C (1.0%) alleles were found in RA, but not SLE cases. Mexican SLE cases displayed the highest frequency of mutant TPMT genotypes worldwide. TPMT genotyping should be performed for Mexican patients with SLE and RA before prescribing purine analogs.
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Affiliation(s)
- Mireya Ramirez-Florencio
- Laboratorio de Genómica del Cáncer, Instituto Nacional de Medicina Genómica, Periferico Sur 4809, Tlalpan, Arenal Tepepan, 14610, Mexico City, CDMX, Mexico
| | - Silvia Jiménez-Morales
- Laboratorio de Genómica del Cáncer, Instituto Nacional de Medicina Genómica, Periferico Sur 4809, Tlalpan, Arenal Tepepan, 14610, Mexico City, CDMX, Mexico.
| | | | - Daniela Josabeth López-Cano
- Unidad de Investigación en Enfermedades Endócrinas y Metabólicas, Hospital Juárez de México, Av. Instituto Politécnico Nacional No. 5160 Delegación Gustavo A. Madero, C.P. 07760, Mexico City, D.F., Mexico
| | - Julian Ramírez-Bello
- Unidad de Investigación en Enfermedades Endócrinas y Metabólicas, Hospital Juárez de México, Av. Instituto Politécnico Nacional No. 5160 Delegación Gustavo A. Madero, C.P. 07760, Mexico City, D.F., Mexico.
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Lauschke VM, Milani L, Ingelman-Sundberg M. Pharmacogenomic Biomarkers for Improved Drug Therapy—Recent Progress and Future Developments. AAPS JOURNAL 2017; 20:4. [DOI: 10.1208/s12248-017-0161-x] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 10/06/2017] [Indexed: 12/13/2022]
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Comparison of Direct Sequencing, Real-Time PCR-High Resolution Melt (PCR-HRM) and PCR-Restriction Fragment Length Polymorphism (PCR-RFLP) Analysis for Genotyping of Common Thiopurine Intolerant Variant Alleles NUDT15 c.415C>T and TPMT c.719A>G (TPMT*3C). Diagnostics (Basel) 2017; 7:diagnostics7020027. [PMID: 28498350 PMCID: PMC5489947 DOI: 10.3390/diagnostics7020027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 05/05/2017] [Accepted: 05/09/2017] [Indexed: 11/29/2022] Open
Abstract
Thiopurine intolerance and treatment-related toxicity, such as fatal myelosuppression, is related to non-function genetic variants encoding thiopurine S-methyltransferase (TPMT) and Nudix hydrolase 15 (NUDT15). Genetic testing of the common variants NUDT15:NM_018283.2:c.415C>T (Arg139Cys, dbSNP rs116855232 T allele) and TPMT: NM_000367.4:c.719A>G (TPMT*3C, dbSNP rs1142345 G allele) in East Asians including Chinese can potentially prevent treatment-related complications. Two complementary genotyping approaches, real-time PCR-high resolution melt (PCR-HRM) and PCR-restriction fragment length morphism (PCR-RFLP) analysis were evaluated using conventional PCR and Sanger sequencing genotyping as the gold standard. Sixty patient samples were tested, revealing seven patients (11.7%) heterozygous for NUDT15 c.415C>T, one patient homozygous for the variant and one patient heterozygous for the TPMT*3C non-function allele. No patient was found to harbor both variants. In total, nine out of 60 (15%) patients tested had genotypic evidence of thiopurine intolerance, which may require dosage adjustment or alternative medication should they be started on azathioprine, mercaptopurine or thioguanine. The two newly developed assays were more efficient and showed complete concordance (60/60, 100%) compared to the Sanger sequencing results. Accurate and cost-effective genotyping assays by real-time PCR-HRM and PCR-RFLP for NUDT15 c.415C>T and TPMT*3C were successfully developed. Further studies may establish their roles in genotype-informed clinical decision-making in the prevention of morbidity and mortality due to thiopurine intolerance.
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Quaranta S, Thomas F. Pharmacogénétique des médicaments anticancéreux : état des connaissances et des pratiques – recommandations du Réseau national de pharmacogénétique (RNPGx). Therapie 2017; 72:193-204. [DOI: 10.1016/j.therap.2016.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/02/2016] [Indexed: 11/26/2022]
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Genetics of inflammatory bowel disease: beyond NOD2. Lancet Gastroenterol Hepatol 2017; 2:224-234. [PMID: 28404137 DOI: 10.1016/s2468-1253(16)30111-x] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 09/02/2016] [Accepted: 09/02/2016] [Indexed: 01/11/2023]
Abstract
The study of the genetic underpinnings of inflammatory bowel disease has made great progress since the identification of NOD2 as a major susceptibility gene. Novel genotyping and sequencing technologies have led to the discovery of 242 common susceptibility loci, 45 of which have been fine-mapped to statistically conclusive causal variants; 50 genes associated with very-early-onset inflammatory disease have been identified. The evolving genetic architecture of inflammatory bowel disease has deepened our understanding of its pathogenesis through identification of major disease associated pathways-knowledge that has the potential to indicate novel drug targets or markers for personalised medicine. However, many causal variants have yet to be identified, and a large proportion of missing heritability still needs to be accounted for. In addition, the medical and scientific communities are probably not yet fully harnessing the power of these genetic discoveries.
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Quaranta S, Thomas F. Pharmacogenetics of anti-cancer drugs: State of the art and implementation - recommendations of the French National Network of Pharmacogenetics. Therapie 2017; 72:205-215. [PMID: 28262261 DOI: 10.1016/j.therap.2017.01.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/02/2016] [Indexed: 12/27/2022]
Abstract
Individualized treatment is of special importance in oncology because the drugs used for chemotherapy have a very narrow therapeutic index. Pharmacogenetics may contribute substantially to clinical routine for optimizing cancer treatment to limit toxic effects while maintaining efficacy. This review presents the usefulness of pharmacogenetic tests for some key applications: dihydropyrimidine dehydrogenase (DPYD) genotyping for fluoropyrimidine (5-fluorouracil, capecitabine), UDP glucuronosylstransferase (UGT1A1) for irinotecan and thiopurine S-methyltransferase (TPMT) for thiopurine drugs. Depending on the level of evidence, the French National Network of Pharmacogenetics (RNPGx) has issued three levels of recommendations for these pharmacogenetic tests: essential, advisable, and potentially useful. Other applications, for which the level of evidence is still discussed, will be evoked in the final section of this review.
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Affiliation(s)
- Sylvie Quaranta
- Service de pharmacocinétique et toxicologie, laboratoire de biologie médicale, hôpital de la Timone, Assistance publique-Hôpitaux de Marseille (AP-HM), 13005 Marseille, France
| | - Fabienne Thomas
- Institut Claudius-Regaud, CRCT, Université de Toulouse, Inserm, UPS, 31059 Toulouse, France; GPCO-Unicancer, 101, rue de Tolbiac, 75013 Paris, France.
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Steponaitiene R, Kupcinskas J, Survilaite S, Varkalaite G, Jonaitis L, Kiudelis G, Denapiene G, Valantinas J, Skieceviciene J, Kupcinskas L. TPMT and ITPA genetic variants in Lithuanian inflammatory bowel disease patients: Prevalence and azathioprine-related side effects. Adv Med Sci 2016; 61:135-40. [PMID: 26674571 DOI: 10.1016/j.advms.2015.09.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 09/09/2015] [Accepted: 09/29/2015] [Indexed: 12/20/2022]
Abstract
PURPOSE Inter-individual thiopurine metabolism variability can influence treatment outcomes in inflammatory bowel disease (IBD) patients. Genetic polymorphisms in thiopurine methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) were linked with toxicity of azathioprine (AZA). The aim of the study was to investigate frequencies of TPMT and ITPA polymorphisms in Lithuanian IBD patients and analyze their association with AZA-related adverse events. MATERIALS/METHODS Polymorphisms in TPMT (TPMT*2,*3B,*3C,*3A) and ITPA (rs1127354, rs7270101) genes were determined using PCR-RFLP and TaqMan(®) genotyping assays. 551 consecutive Lithuanian IBD patients were genotyped. The use of AZA and its side effects were assessed retrospectively according to hospital medical records. RESULTS Frequencies of TPMT*3A, TPMT*3B and TPMT*3C alleles were 3.1%, 0.5% and 0.1%, respectively. TPMT*2 genetic variant was not detected in the study group. The distribution of minor alleles for ITPA rs1127354 and rs7270101 polymorphisms was 9.9% and 10.5%, respectively. AZA was prescribed in 82 patients and it provoked myelotoxicity in 11%, hepatotoxicity in 6.1%, dyspepsia in 6.1%, and pancreatitis in 3.6% of cases. Among patients who had AZA-related myelotoxicity, 11.1% were TPMT compound heterozygous, 44.4% had heterozygous genotype (P<0.01). Frequencies of ITPA minor alleles were similar among the patients with and without AZA-related side effects. CONCLUSION Frequencies of TPMT and ITPA variant alleles in Lithuanian IBD group were similar to those observed in the Northern-Eastern Europe Caucasian populations. Polymorphisms in TPMT might be associated with myelotoxicity and leukopenia in AZA treated patients, while ITPA variant alleles appear not to be linked with treatment-related side effects.
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Affiliation(s)
- Ruta Steponaitiene
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Juozas Kupcinskas
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania; Department of Gastroenterology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Santa Survilaite
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Greta Varkalaite
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Laimas Jonaitis
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania; Department of Gastroenterology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Gediminas Kiudelis
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania; Department of Gastroenterology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Goda Denapiene
- Clinic of Gastroenterology, Nephrourology and Surgery, Medical Faculty of Vilnius University, Vilnius University, Vilnius, Lithuania
| | - Jonas Valantinas
- Clinic of Gastroenterology, Nephrourology and Surgery, Medical Faculty of Vilnius University, Vilnius University, Vilnius, Lithuania
| | - Jurgita Skieceviciene
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Limas Kupcinskas
- Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania; Department of Gastroenterology, Lithuanian University of Health Sciences, Kaunas, Lithuania.
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Rovaris DL, Mota NR, da Silva BS, Girardi P, Victor MM, Grevet EH, Bau CH, Contini V. Should we keep on? Looking into pharmacogenomics of ADHD in adulthood from a different perspective. Pharmacogenomics 2015; 15:1365-81. [PMID: 25155937 DOI: 10.2217/pgs.14.95] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A considerable proportion of adults with attention-deficit/hyperactivity disorder (ADHD) do not respond to the treatment with methylphenidate. This scenario could be due to inherited interindividual differences that may alter pharmacologic treatment response. In this sense, in 2012 we conducted a systematic search on PUBMED-indexed literature for articles containing information about pharmacogenomics of ADHD in adults. Five studies were found on methylphenidate pharmacogenomics and the only significant association was reported by one particular study. However, this single association with the SLC6A3 gene was not replicated in two subsequent reports. In the present review, although we could not find additional pharmacogenomics studies, we discuss these up-to-date findings and suggest new approaches for this field. Additionally, using systeomic-oriented databases, we provide a broad picture of new possible candidate genes as well as potential gene-gene interactions to be investigated in pharmacogenomics of persistent ADHD.
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Affiliation(s)
- Diego L Rovaris
- Departament of Genetics, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Brazil
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Genotype and allele frequencies of drug-metabolizing enzymes and drug transporter genes affecting immunosuppressants in the Spanish white population. Ther Drug Monit 2015; 36:159-68. [PMID: 24232128 DOI: 10.1097/ftd.0b013e3182a94e65] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Interpatient variability in drug response can be widely explained by genetically determined differences in metabolizing enzymes, drug transporters, and drug targets, leading to different pharmacokinetic and/or pharmacodynamic behaviors of drugs. Genetic variations affect or do not affect drug responses depending on their influence on protein activity and the relevance of such proteins in the pathway of the drug. Also, the frequency of such genetic variations differs among populations, so the clinical relevance of a specific variation is not the same in all of them. In this study, a panel of 33 single nucleotide polymorphisms in 14 different genes (ABCB1, ABCC2, ABCG2, CYP2B6, CYP2C19, CYP2C9, CYP3A4, CYP3A5, MTHFR, NOD2/CARD15, SLCO1A2, SLCO1B1, TPMT, and UGT1A9), encoding for the most relevant metabolizing enzymes and drug transporters relating to immunosuppressant agents, was analyzed to determine the genotype profile and allele frequencies in comparison with HapMap data. A total of 570 Spanish white recipients and donors of solid organ transplants were included. In 24 single nucleotide polymorphisms, statistically significant differences in allele frequency were observed. The largest differences (>100%) occurred in ABCB1 rs2229109, ABCG2 rs2231137, CYP3A5 rs776746, NOD2/CARD15 rs2066844, TPMT rs1800462, and UGT1A9 rs72551330. In conclusion, differences were recorded between the Spanish and other white populations in terms of allele frequency and genotypic distribution. Such differences may have implications in relation to dose requirements and drug-induced toxicity. These data are important for further research to help explain interindividual pharmacokinetic and pharmacodynamic variability in response to drug therapy.
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Avula R, O'Kane D, Black JL. Alternative method of allelic discrimination. Biotechniques 2014; 57:88-90. [PMID: 25109294 DOI: 10.2144/000114199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 07/18/2014] [Indexed: 11/23/2022] Open
Abstract
5' nuclease assays for allelic discrimination use both a wild-type and a mutant probe. Here we present a new method for genotyping by 5' nuclease assays that dispenses with the mutant probe, using the wild-type probe together with a probe for a reference gene known to be present in two copies to determine the copy number of the wild type allele relative to the reference gene. The copy number of the wild-type allele then determines the genotype: two copies indicates homozygous wild-type; one copy indicates heterozygous; and zero copies indicates homozygous mutant. We were able to use our method to correctly genotype three alleles of the thiopurine methyl transferase (TPMT) gene: TPMT *2 (c.G238C), *3B (c.G460A) and *3C (c.A719G). Our approach can be used as an alternate allelic discrimination strategy that is cost effective when multiple TaqMan assays are performed on a sample.
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Affiliation(s)
- Rajeswari Avula
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | - Dennis O'Kane
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | - John L Black
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
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Enhanced specificity of TPMT*2 genotyping using unidirectional wild-type and mutant allele-specific scorpion primers in a single tube. PLoS One 2014; 9:e91824. [PMID: 24705376 PMCID: PMC3976262 DOI: 10.1371/journal.pone.0091824] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 02/16/2014] [Indexed: 12/29/2022] Open
Abstract
Genotyping of thiopurine S-methyltransferase (TPMT) is recommended for predicting the adverse drug response of thiopurines. In the current study, a novel version of allele-specific PCR (AS-PCR), termed competitive real-time fluorescent AS-PCR (CRAS-PCR) was developed to analyze the TPMT*2 genotype in ethnic Chinese. This technique simultaneously uses wild-type and mutant allele-specific scorpion primers in a single reaction. To determine the optimal conditions for both traditional AS-PCR and CRAS-PCR, we used the Taguchi method, an engineering optimization process that balances the concentrations of all components using an orthogonal array rather than a factorial array. Instead of running up to 264 experiments with the conventional factorial method, the Taguchi method achieved the same optimization using only 16 experiments. The optimized CRAS-PCR system completely avoided non-specific amplification occurring in traditional AS-PCR and could be performed at much more relaxed reaction conditions at 1% sensitivity, similar to traditional AS-PCR. TPMT*2 genotyping of 240 clinical samples was consistent with published data. In conclusion, CRAS-PCR is a novel and robust genotyping method, and the Taguchi method is an effective tool for the optimization of molecular analysis techniques.
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Maruyama H, Tada K, Fujiwara T, Ota K, Kageyama M. Utility of maternal 6-thioguanine nucleotide levels in predicting neonatal pancytopenia. AJP Rep 2013; 3:25-8. [PMID: 23943705 PMCID: PMC3699157 DOI: 10.1055/s-0032-1329683] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 07/27/2012] [Indexed: 10/27/2022] Open
Abstract
An infant with pancytopenia was born to a mother who used the common immunosuppressant azathioprine (AZA). Maternal and neonatal blood levels of 6-thioguanine nucleotides (6TGN; metabolite of AZA) were 1890 and 1480 pmol/8 × 10(8) red blood cells, respectively. Maternal 6TGN levels could be useful in predicting neonatal pancytopenia.
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Affiliation(s)
- Hidehiko Maruyama
- Department of Neonatology, National Hospital Organization, Okayama Medical Center, Okayama, Japan
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Elawi AM, Irshaid YM, Ismail SI, Mustafa KN. Thiopurine S-methytransferase gene polymorphism in rheumatoid arthritis. Arch Med Res 2013; 44:105-9. [PMID: 23398787 DOI: 10.1016/j.arcmed.2013.01.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 01/17/2013] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND AIMS Thiopurine S-methyltransferase (TPMT) is responsible for inactivation of thiopurine drugs which are commonly used in leukemia, organ transplantation and autoimmune diseases. The gene encoding TPMT is polymorphic, and both phenotyping and genotyping studies have shown ethnic variations in gene sequence and enzyme activity worldwide. The aim of this study is to identify the most common genetic polymorphisms of TPMT in healthy Jordanian volunteers and patients with rheumatoid arthritis (RA). METHODS A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used to identify the frequency of TPMT (*2, *3A, *3B, and *3C) polymorphisms in 250 healthy Jordanian volunteers and 110 RA patients. RESULTS Only four healthy subjects (1.6%) and one RA patient (0.9%) with variant alleles were identified in this study. Two healthy subjects had the TPMT*3A allele and the other two had the TPMT*3B allele, whereas the one RA patient had the TPMT*3A allele. No homozygous polymorphisms were detected and all genotypes detected were heterozygous (*1/*3A) (*1/*3B). None of the subjects had TPMT*2 or TPMT*3C variant alleles. CONCLUSIONS Mutant alleles identified in this study have a low frequency. TPMT (*3A and *3B) were the only detected heterozygous alleles. No homozygous variant allele was detected. Further studies are necessary to identify other variant alleles that might uniquely occur in Jordanians.
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Affiliation(s)
- Asma M Elawi
- Department of Pharmacology, Faculty of Medicine, The University of Jordan, Amman, Jordan
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Pharmacogenetic determinants of mercaptopurine disposition in children with acute lymphoblastic leukemia. Eur J Clin Pharmacol 2012; 68:1233-42. [PMID: 22421815 DOI: 10.1007/s00228-012-1251-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Accepted: 02/14/2012] [Indexed: 12/15/2022]
Abstract
BACKGROUND The backbone of drug therapy used in acute lymphoblastic leukemia (ALL) in children includes 6-mercaptopurine (6-MP). Intracellular metabolism of this prodrug is a key component of the therapeutic response. Many metabolizing enzymes are involved in 6-MP disposition and active 6-MP metabolites are represented by 6-thioguanine nucleotides (6-TGN) and methylated metabolites primarily methylated by the thiopurine S-methyltransferase enzyme (TPMT). The genetic polymorphism affecting TPMT activity displays an important inter-subject variability in metabolites pharmacokinetics and influences the balance between 6-MP efficacy and toxicity: patients with high 6-TGN levels are at risk of myelosuppression while patients with high levels of methylated derivates are at hepatotoxic risk. However, the genetic TPMT polymorphism does not explain all 6-MP adverse events and some severe toxicities leading to life-threatening conditions remain unexplained. Additional single nucleotide polymorphisms (SNPs) in genes encoding enzymes involved in 6-MP metabolism and 6-MP transporters may also be responsible for this inter-individual 6-MP response variability. AIM This review presents the pharmacogenetic aspects of 6-MP metabolism in great detail. We have focused on published data on ALL treatment supporting the great potential of 6-MP pharmacogenetics to improve efficacy, tolerance, and event-free survival rates in children with ALL.
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Ciccolini J, Evrard A, M’Batchi L, Pourroy B, Mercier C, Iliadis A, Lacarelle B, Verschuur A, Ouafik L, André N. CDA deficiency as a possible culprit for life-threatening toxicities after cytarabine plus 6-mercaptopurine therapy: pharmacogenetic investigations. Pharmacogenomics 2012; 13:393-7. [DOI: 10.2217/pgs.11.175] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We describe here the case of a 7-year old girl with lymphoma who developed life-threatening toxicities upon cytarabine plus mercaptopurine. Surprisingly, initial investigations on canonical thiopurine methyltransferase genetic polymorphism proved to be negative. We focused next on deregulations affecting the CDA gene implicated in the liver disposition of cytarabine. This patient was homozygous for both the 79A>C and the -31delC polymorphisms on the CDA gene and promoter, two genotypes with reported opposite effects on CDA phenotype. To determine the CDA status of this patient, additional functional testing was performed and eventually demonstrated that this patient was a poor metabolizer. This case demonstrates that besides affecting thiopurine methyltransferase, dysregulations with CDA should be screened to anticipate toxicities with the cytarabine plus mercaptopurine combination.
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Affiliation(s)
- Joseph Ciccolini
- Laboratoire de Pharmacocinétique, La Timone University Hospital of Marseille, UMR 911, Aix-Marseille University, Marseille, France
- Laboratoire de Transfert en Oncologie, Nord University Hospital of Marseille, UMR 911, Aix-Marseille University, Marseille, France
- Pharmacokinetics Laboratory, UMR 911, Aix-Marseille University, Marseille, France
| | - Alexandre Evrard
- Clinical Biochemistry Laboratory, Caremeau University Hospital of Nîmes, France
| | - Lithaty M’Batchi
- Clinical Biochemistry Laboratory, Caremeau University Hospital of Nîmes, France
| | - Bertrand Pourroy
- Pharmacy Departement, La Timone University Hospital of Marseille, France
| | - Cédric Mercier
- Pharmacokinetics Laboratory, UMR 911, Aix-Marseille University, Marseille, France
| | - Athanassios Iliadis
- Pharmacokinetics Laboratory, UMR 911, Aix-Marseille University, Marseille, France
| | - Bruno Lacarelle
- Laboratoire de Pharmacocinétique, La Timone University Hospital of Marseille, UMR 911, Aix-Marseille University, Marseille, France
- Pharmacokinetics Laboratory, UMR 911, Aix-Marseille University, Marseille, France
| | - Arnaud Verschuur
- Hematology & Oncology Pediatric Department, Hôpital-Enfants La Timone, AP-HM, 235 rue St Pierre, 13885 Marseille Cedex 5, France
| | - L’Houcine Ouafik
- Laboratoire de Transfert en Oncologie, Nord University Hospital of Marseille, UMR 911, Aix-Marseille University, Marseille, France
| | - Nicolas André
- Hematology & Oncology Pediatric Department, Hôpital-Enfants La Timone, AP-HM, 235 rue St Pierre, 13885 Marseille Cedex 5, France
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Abstract
Antimetabolites are cytotoxic agents, which have been developed for more than 50 years. Which cancer patient did not receive or will not receive 5-fluorouracil or methotrexate during the evolution his or her disease? Antimetabolites are defined as interfering with the synthesis of the DNA constituents; they are structural analogues, either of purine and pyrimidine bases (or the corresponding nucleosides), or of folate cofactors, which are involved at several steps of purine and pyrimidine biosynthesis. Their first mechanism of action is, therefore, to induce depletion in nucleotides inducing in turn an inhibition of DNA replication. However, some of them are able to get inserted fraudulently into nucleic acids, inducing structural abnormalities leading to cell death by other mechanisms, including DNA breaks. We present in this paper, for the three classes of antimetabolites, both ancient and recent molecules as well as molecules still in clinical trials, without exhaustivity.
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Moini M, Ghaderi F, Sagheb MM, Tavasolli AR, Azarpira N, Darai M, Geramizadeh B. The frequency and distribution of thiopurine S-methyltransferase alleles in south Iranian population. Mol Biol Rep 2011; 39:4581-7. [PMID: 21938428 DOI: 10.1007/s11033-011-1248-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Accepted: 09/14/2011] [Indexed: 01/29/2023]
Abstract
Thiopurine methyltransferase (TPMT) catalyzes the S-methylation of thiopurine drugs such as 6-mercaptopurine, 6-thioguanine, and azathiopurine. Variability in TPMT activity is mainly due to genetic polymorphism. The frequency of the four allelic variants of the TPMT gene, TPMT*2 (G238C), TPMT*3A (G460A and A719G), TPMT*3B (G460A) and TPMT*3C (A719G) were determined in an Iranian population from south of Iran (n = 500), using polymerase chain reaction (PCR)-RFLP and allele-specific PCR-based assays. Four hundred seventy four persons (94.8%) were homozygous for the wild type allele (TPMT*1/*1) and twenty five people were TPMT*1/*3C (5%). One patient was found to be heterozygous in terms TPMT*1 and *2 alleles with genotype of TPMT*1/*2 (0.2%). None of the participants had both defective alleles. The TPMT*3C and *2 were the only variant alleles observed in this population. The total frequency of variant alleles was 2.6% and the wild type allele frequency was 97.4%. The TPMT*3B and *3A alleles were not detected. Distributions of TPMT genotype and allele frequency in Iranian populations are different from the genetic profile found among Caucasian or Asian populations. Our findings also revealed inter-ethnic differences in TPMT frequencies between different parts of Iran. This view may help clinicians to choose an appropriate strategy for thiopurine drugs and reduce adverse drug reactions such as bone marrow suppression.
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Affiliation(s)
- Maryam Moini
- Department of Internal Medicine, Gastroenterology and Hepatology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
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