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Fabo T, Khavari P. Functional characterization of human genomic variation linked to polygenic diseases. Trends Genet 2023; 39:462-490. [PMID: 36997428 PMCID: PMC11025698 DOI: 10.1016/j.tig.2023.02.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 03/30/2023]
Abstract
The burden of human disease lies predominantly in polygenic diseases. Since the early 2000s, genome-wide association studies (GWAS) have identified genetic variants and loci associated with complex traits. These have ranged from variants in coding sequences to mutations in regulatory regions, such as promoters and enhancers, as well as mutations affecting mediators of mRNA stability and other downstream regulators, such as 5' and 3'-untranslated regions (UTRs), long noncoding RNA (lncRNA), and miRNA. Recent research advances in genetics have utilized a combination of computational techniques, high-throughput in vitro and in vivo screening modalities, and precise genome editing to impute the function of diverse classes of genetic variants identified through GWAS. In this review, we highlight the vastness of genomic variants associated with polygenic disease risk and address recent advances in how genetic tools can be used to functionally characterize them.
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Affiliation(s)
- Tania Fabo
- Program in Epithelial Biology, Stanford University, Stanford, CA, USA; Stanford Cancer Institute, Stanford University, Stanford, CA, USA; Graduate Program in Genetics, Stanford University, Stanford, CA, USA; Stanford University School of Medicine, Stanford University, Stanford, CA, USA
| | - Paul Khavari
- Program in Epithelial Biology, Stanford University, Stanford, CA, USA; Stanford Cancer Institute, Stanford University, Stanford, CA, USA; Graduate Program in Genetics, Stanford University, Stanford, CA, USA; Stanford University School of Medicine, Stanford University, Stanford, CA, USA; Veterans Affairs Palo Alto Healthcare System, Palo Alto, CA, USA.
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2
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Chamboko CR, Veldman W, Tata RB, Schoeberl B, Tastan Bishop Ö. Human Cytochrome P450 1, 2, 3 Families as Pharmacogenes with Emphases on Their Antimalarial and Antituberculosis Drugs and Prevalent African Alleles. Int J Mol Sci 2023; 24:ijms24043383. [PMID: 36834793 PMCID: PMC9961538 DOI: 10.3390/ijms24043383] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/30/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
Precision medicine gives individuals tailored medical treatment, with the genotype determining the therapeutic strategy, the appropriate dosage, and the likelihood of benefit or toxicity. Cytochrome P450 (CYP) enzyme families 1, 2, and 3 play a pivotal role in eliminating most drugs. Factors that affect CYP function and expression have a major impact on treatment outcomes. Therefore, polymorphisms of these enzymes result in alleles with diverse enzymatic activity and drug metabolism phenotypes. Africa has the highest CYP genetic diversity and also the highest burden of malaria and tuberculosis, and this review presents current general information on CYP enzymes together with variation data concerning antimalarial and antituberculosis drugs, while focusing on the first three CYP families. Afrocentric alleles such as CYP2A6*17, CYP2A6*23, CYP2A6*25, CYP2A6*28, CYP2B6*6, CYP2B6*18, CYP2C8*2, CYP2C9*5, CYP2C9*8, CYP2C9*9, CYP2C19*9, CYP2C19*13, CYP2C19*15, CYP2D6*2, CYP2D6*17, CYP2D6*29, and CYP3A4*15 are implicated in diverse metabolic phenotypes of different antimalarials such as artesunate, mefloquine, quinine, primaquine, and chloroquine. Moreover, CYP3A4, CYP1A1, CYP2C8, CYP2C18, CYP2C19, CYP2J2, and CYP1B1 are implicated in the metabolism of some second-line antituberculosis drugs such as bedaquiline and linezolid. Drug-drug interactions, induction/inhibition, and enzyme polymorphisms that influence the metabolism of antituberculosis, antimalarial, and other drugs, are explored. Moreover, a mapping of Afrocentric missense mutations to CYP structures and a documentation of their known effects provided structural insights, as understanding the mechanism of action of these enzymes and how the different alleles influence enzyme function is invaluable to the advancement of precision medicine.
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Affiliation(s)
- Chiratidzo R Chamboko
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
| | - Wayde Veldman
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
| | - Rolland Bantar Tata
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
| | - Birgit Schoeberl
- Translational Medicine, Novartis Institutes for BioMedical Research, 220 Massachusetts Ave, Cambridge, MA 02139, USA
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
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Silva-Alarcon S, Valencia C, Newball L, Saldarriaga W, Castillo A. Molecular Variants in Genes related to the Response to Ocular Hypotensive Drugs in an Afro-Colombian Population. Open Ophthalmol J 2022. [DOI: 10.2174/18743641-v16-e2205250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aims:
This study aimed to conduct an exploratory analysis of the pharmacogenomic variants involved in ocular hypotensive drugs to understand the individual differential response in an Afro-descendant population.
Background:
Glaucoma is the leading cause of irreversible blindness worldwide. The pharmacologic treatment available consists of lowering intraocular pressure by administering topical drugs. In Asian and Caucasian people, pharmacogenomic variants associated with the efficacy of these treatments have been identified. However, in Afro-descendant populations, there is a profound gap in this knowledge.
Objective:
This study identified the pharmacogenomic variants related to ocular hypotensive efficacy treatment in Afro-descendant individuals from the Archipelago of San Andres and Providence, Colombia.
Methods:
An analysis of whole-exome sequencings (WES), functional annotation, and clinical significance was performed for pharmacogenomic variants reported in PharmGKB databases; in turn, an in silico available prediction analysis was carried out for the novel variants.
Results:
We identified six out of 18 non-synonymous variants with a clinical annotation in PharmGKB. Five were classified as level three evidence for the hypotensive drugs; rs1801252 and rs1801253 in the ADRB1 gene and rs1042714 in the ADRB2 gene. These pharmacogenomic variants have been involved in a lack of efficacy of topical beta-blockers and higher systolic and diastolic pressure under treatment with ophthalmic timolol drug. The rs1045642 in the ABCB1 gene was associated with greater efficacy of treatments with latanoprost drug. Also, we found the haplotypes *17 for CYP2D6 and *10 for CYP2C19; both related to reducing the enzyme activity to timolol drug metabolization. In addition, we observed 50 novel potentially actionable variants; 36 synonymous, two insertion variants that caused frameshift mutations, and 12 non-synonymous, where five were predicted to be pathogenic based on several pathogenicity predictions.
Conclusion:
Our results suggested that the pharmacogenomic variants were found to decrease the ocular hypotensive efficacy treatment in a Colombian Afro-descendant population and revealed a significant proportion of novel variants with a potential to influence drug response.
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Hu M, Li Y, You F, Bai J, Fan X, Zhao S, Sun Y, Wang B, Hu J, Li Y. Comparison and identification of metabolic profiling of bicyclol in rats, dogs and humans in vitro and in vivo. Eur J Pharm Sci 2020; 154:105518. [PMID: 32818657 DOI: 10.1016/j.ejps.2020.105518] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/07/2020] [Accepted: 08/17/2020] [Indexed: 01/31/2023]
Abstract
Bicyclol, a novel hepatoprotective agent, has been widely used to treat chronic viral hepatitis and drug-induced liver injury (DILI). However, its metabolic characteristics remains to be explored, especially in humans. The current study aimed to identify major metabolites and specific metabolizing enzymes involved in bicyclol metabolism in vitro and in vivo using high performance liquid chromatography coupled with Q-Exactive orbitrap mass spectrometry (HPLC-Q-Exactive Orbitrap/MS). After incubation with liver microsomes and oral administration to rats, dogs and humans, a total of nine metabolites of bicyclol were identified including M1 (methyl ester hydrolysate product), M2-M3 (demethylated bicyclol), M4-M5 (demethoxy or dehydroxymethyl bicyclol), M6 (glucuronidated bicyclol) and M7-M9 (glucuronide conjugates of metabolites). Among these metabolites, M2 and M3 were the major phase I metabolites mainly mediated by CYP2C19 and CYP3A4, while M6 was the dominant phase II metabolite primarily catalyzed by UGT2B4. In this study, species-related metabolic difference among rats, dogs and humans were observed. In humans and dogs, M6 (glucuronidated bicyclol) was the most abundant circulating metabolite (higher than the parent drug) in the blood after oral administration, while the parent drug was the highest in rats. M4 and M5 were rats-specific metabolites whereas M1 and M9 were absent in dogs in vivo. The metabolism of bicyclol was demonstrated as demethylation and glucuronidation mediated by multiple drug metabolizing enzymes in different species. Our findings systematically elucidated the metabolic sites and routes of bicyclol in human for the first time, which may be helpful for rational combined application in clinic and further study of metabolites-related efficacy or toxicity.
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Affiliation(s)
- Minwan Hu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Yang Li
- Beijing Union Pharmaceutical Facroty, Beijing, 102600, China
| | - Feng You
- Beijing Union Pharmaceutical Facroty, Beijing, 102600, China
| | - Jie Bai
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Xiaoqing Fan
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Shengyu Zhao
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Yanhong Sun
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Baolian Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China.
| | - Jinping Hu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China.
| | - Yan Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
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Morales-Rosado JA, Goel K, Zhang L, Åkerblom A, Baheti S, Black JL, Eriksson N, Wallentin L, James S, Storey RF, Goodman SG, Jenkins GD, Eckloff BW, Bielinski SJ, Sicotte H, Johnson S, Roger VL, Wang L, Weinshilboum R, Klee EW, Rihal CS, Pereira NL. Next-Generation Sequencing of CYP2C19 in Stent Thrombosis: Implications for Clopidogrel Pharmacogenomics. Cardiovasc Drugs Ther 2020; 35:549-559. [PMID: 32623598 DOI: 10.1007/s10557-020-06988-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE Describe CYP2C19 sequencing results in the largest series of clopidogrel-treated cases with stent thrombosis (ST), the closest clinical phenotype to clopidogrel resistance. Evaluate the impact of CYP2C19 genetic variation detected by next-generation sequencing (NGS) with comprehensive annotation and functional studies. METHODS Seventy ST cases on clopidogrel identified from the PLATO trial (n = 58) and Mayo Clinic biorepository (n = 12) were matched 1:1 with controls for age, race, sex, diabetes mellitus, presentation, and stent type. NGS was performed to cover the entire CYP2C19 gene. Assessment of exonic variants involved measuring in vitro protein expression levels. Intronic variants were evaluated for potential splicing motif variations. RESULTS Poor metabolizers (n = 4) and rare CYP2C19*8, CYP2C19*15, and CYP2C19*11 alleles were identified only in ST cases. CYP2C19*17 heterozygote carriers were observed more frequently in cases (n = 29) than controls (n = 18). Functional studies of CYP2C19 exonic variants (n = 11) revealed 3 cases and only 1 control carrying a deleterious variant as determined by in vitro protein expression studies. Greater intronic variation unique to ST cases (n = 169) compared with controls (n = 84) was observed with predictions revealing 13 allele candidates that may lead to a potential disruption of splicing and a loss-of-function effect of CYP2C19 in ST cases. CONCLUSION NGS detected CYP2C19 poor metabolizers and paradoxically greater number of so-called rapid metabolizers in ST cases. Rare deleterious exonic variation occurs in 4%, and potentially disruptive intronic alleles occur in 16% of ST cases. Additional studies are required to evaluate the role of these variants in platelet aggregation and clopidogrel metabolism.
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Affiliation(s)
- Joel A Morales-Rosado
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA.,Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Kashish Goel
- Vanderbilt University School of Medicine, Nashville, TN, 37215, USA
| | - Lingxin Zhang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
| | - Axel Åkerblom
- Department of Medical Sciences, Cardiology and Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden
| | - Saurabh Baheti
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - John L Black
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Niclas Eriksson
- Department of Medical Sciences, Cardiology and Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden
| | - Lars Wallentin
- Department of Medical Sciences, Cardiology and Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden
| | - Stefan James
- Department of Medical Sciences, Cardiology and Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden
| | - Robert F Storey
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Shaun G Goodman
- St. Michael's Hospital, University of Toronto, Toronto, Canada.,Canadian VIGOUR Centre, University of Alberta , Edmonton, Canada
| | - Gregory D Jenkins
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | | | - Suzette J Bielinski
- Division of Epidemiology, Mayo Clinic, Department of Health Sciences Research, Rochester, MN, USA
| | - Hugues Sicotte
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - Stephen Johnson
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - Veronique L Roger
- Department of Cardiovascular Medicine, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA
| | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
| | - Richard Weinshilboum
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
| | - Eric W Klee
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA.,Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Charanjit S Rihal
- Department of Cardiovascular Medicine, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA
| | - Naveen L Pereira
- Department of Cardiovascular Medicine, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA.
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D'Arcy MS. A review of the chemopreventative and chemotherapeutic properties of the phytochemicals berberine, resveratrol and curcumin, and their influence on cell death via the pathways of apoptosis and autophagy. Cell Biol Int 2020; 44:1781-1791. [PMID: 32449796 DOI: 10.1002/cbin.11402] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 05/15/2020] [Accepted: 05/23/2020] [Indexed: 12/22/2022]
Abstract
Phytochemicals are a diverse group of compounds found in a variety of fruits, vegetables and herbs, and have been reported to possess a number of health benefits. Marketed as supplements by health food retailers, this group of naturally occurring compounds have been investigated for a number of years to determine if they possess any chemopreventative and/or chemotherapeutic benefits. In this comprehensive review, the phytochemicals resveratrol, berberine and curcumin will be discussed, with particular focus being given to their proposed anticancer applications. The purpose of this review is to help clarify whether there is any truth in the claims that are regularly made regarding the efficacy of these compounds. To this end, a number of significant studies that involved the use of these phytochemicals will be identified, discussed and evaluated, to determine if they show promise in the ongoing fight to reduce the incidence rates and severity of various cancers. Specifically, it is the aim of this review to present and discuss key studies performed over the last two decades using these compounds and to evaluate, compare and contrast their effectiveness as chemopreventatives and chemotherapeutics. This should provide the reader with an overarching picture of how these structurally similar phytochemicals might be used in both clinical and nonclinical settings, as a part of the ongoing effort by clinicians, to help to slow down the increasing rate of cancers observed over the last few decades.
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Affiliation(s)
- Mark Sean D'Arcy
- Biology Division, Hertfordshire International College, College Lane Campus, Hatfield, UK
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7
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Dong AN, Ahemad N, Pan Y, Palanisamy UD, Yiap BC, Ong CE. The Molecular and Enzyme Kinetic Basis for Altered Activity of Three Cytochrome P450 2C19 Variants Found in the Chinese Population. Curr Mol Pharmacol 2019; 13:233-244. [PMID: 31713493 DOI: 10.2174/1874467212666191111110429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 10/27/2019] [Accepted: 10/29/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND There is a large inter-individual variation in cytochrome P450 2C19 (CYP2C19) activity. The variability can be caused by the genetic polymorphism of CYP2C19 gene. This study aimed to investigate the molecular and kinetics basis for activity changes in three alleles including CYP2C19*23, CYP2C19*24 and CYP2C19*25found in the Chinese population. METHODS The three variants expressed by bacteria were investigated using substrate (omeprazole and 3- cyano-7-ethoxycoumarin[CEC]) and inhibitor (ketoconazole, fluoxetine, sertraline and loratadine) probes in enzyme assays along with molecular docking. RESULTS All alleles exhibited very low enzyme activity and affinity towards omeprazole and CEC (6.1% or less in intrinsic clearance). The inhibition studies with the four inhibitors, however, suggested that mutations in different variants have a tendency to cause enhanced binding (reduced IC50 values). The enhanced binding could partially be explained by the lower polar solvent accessible surface area of the inhibitors relative to the substrates. Molecular docking indicated that G91R, R335Q and F448L, the unique mutations in the alleles, have caused slight alteration in the substrate access channel morphology and a more compact active site cavity hence affecting ligand access and binding. It is likely that these structural alterations in CYP2C19 proteins have caused ligand-specific alteration in catalytic and inhibitory specificities as observed in the in vitro assays. CONCLUSION This study indicates that CYP2C19 variant selectivity for ligands was not solely governed by mutation-induced modifications in the active site architecture, but the intrinsic properties of the probe compounds also played a vital role.
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Affiliation(s)
- Amelia Nathania Dong
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Nafees Ahemad
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Yan Pan
- Department of Biomedical Science, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
| | - Uma Devi Palanisamy
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Beow Chin Yiap
- School of Pharmacy, International Medical University, 126, Jalan Jalil Perkasa 19, Bukit Jalil, 57000 Kuala Lumpur, Malaysia
| | - Chin Eng Ong
- School of Pharmacy, International Medical University, 126, Jalan Jalil Perkasa 19, Bukit Jalil, 57000 Kuala Lumpur, Malaysia
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Pharmacogenomic Impact of CYP2C19 Variation on Clopidogrel Therapy in Precision Cardiovascular Medicine. J Pers Med 2018; 8:jpm8010008. [PMID: 29385765 PMCID: PMC5872082 DOI: 10.3390/jpm8010008] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/20/2018] [Accepted: 01/22/2018] [Indexed: 12/21/2022] Open
Abstract
Variability in response to antiplatelet therapy can be explained in part by pharmacogenomics, particularly of the CYP450 enzyme encoded by CYP2C19. Loss-of-function and gain-of-function variants help explain these interindividual differences. Individuals may carry multiple variants, with linkage disequilibrium noted among some alleles. In the current pharmacogenomics era, genomic variation in CYP2C19 has led to the definition of pharmacokinetic phenotypes for response to antiplatelet therapy, in particular, clopidogrel. Individuals may be classified as poor, intermediate, extensive, or ultrarapid metabolizers, based on whether they carry wild type or polymorphic CYP2C19 alleles. Variant alleles differentially impact platelet reactivity, concentration of plasma clopidogrel metabolites, and clinical outcomes. Interestingly, response to clopidogrel appears to be modulated by additional factors, such as sociodemographic characteristics, risk factors for ischemic heart disease, and drug-drug interactions. Furthermore, systems medicine studies suggest that a broader approach may be required to adequately assess, predict, preempt, and manage variation in antiplatelet response. Transcriptomics, epigenomics, exposomics, miRNAomics, proteomics, metabolomics, microbiomics, and mathematical, computational, and molecular modeling should be integrated with pharmacogenomics for enhanced prediction and individualized care. In this review of pharmacogenomic variation of CYP450, a systems medicine approach is described for tailoring antiplatelet therapy in clinical practice of precision cardiovascular medicine.
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Dehbozorgi M, Kamalidehghan B, Hosseini I, Dehghanfard Z, Sangtarash MH, Firoozi M, Ahmadipour F, Meng GY, Houshmand M. Prevalence of the CYP2C19*2 (681 G>A), *3 (636 G>A) and *17 (‑806 C>T) alleles among an Iranian population of different ethnicities. Mol Med Rep 2018; 17:4195-4202. [PMID: 29328413 PMCID: PMC5802190 DOI: 10.3892/mmr.2018.8377] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 06/29/2017] [Indexed: 11/30/2022] Open
Abstract
Polymorphisms in the cytochrome P (CYP) 450 family may cause adverse drug responses in individuals. Cytochrome P450 2C19 (CYP2C19) is a member of the CYP family, where the presence of the 681 G>A, 636 G>A and 806 C>T polymorphisms result in the CYP2C19*2, CYP2C19*3 and CYP2C19*17 alleles, respectively. In the current study, the frequency of the CYP2C19*2, CYP2C19*3 and CYP2C19*17 alleles in an Iranian population cohort of different ethnicities were examined and then compared with previously published frequencies within other populations. Allelic and genotypic frequencies of the CYP2C19 alleles (*2, *3 and *17) were detected using polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis, PCR-single-strand conformation polymorphism analysis and DNA sequencing from blood samples of 1,229 unrelated healthy individuals from different ethnicities within the Iranian population. The CYP2C19 allele frequencies among the Iranian population were 21.4, 1.7, and 27.1% for the CYP2C19*2, CYP2C19*3 and CYP2C19*17 alleles, respectively. The frequency of the homozygous A/A variant of the CYP2C19*2 allele was significantly high and low in the Lur (P<0.001) and Caspian (P<0.001) ethnicities, respectively. However, the frequency of the homozygous A/A variant of the CYP2C19*3 allele was not detected in the Iranian cohort in the current study. The frequency of the heterozygous G/A variant of the CYP2C19*3 allele had the significantly highest and lowest frequency in the Fars (P<0.001) and Lur (P<0.001) groups, respectively. The allele frequency of the homozygous T/T variant of the CYP2C19*17 allele was significantly high in the Caspian (P<0.001) and low in the Kurd (P<0.05) groups. The frequency of the CYP2C19 alleles involved in drug metabolism, may improve the clinical understanding of the ethnic differences in drug responses, resulting in the advancement of the personalized medicine among the different ethnicities within the Iranian population.
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Affiliation(s)
- Mahshid Dehbozorgi
- Department of Biology, University of Sistan and Baluchestan, Zahedan 98155‑987, Iran
| | - Behnam Kamalidehghan
- Medical Genetics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran 198396‑3113, Iran
| | - Iman Hosseini
- Department of Cellular and Molecular Biology, Nourdanesh Institute of Higher Education, Isfahan 8351711111, Iran
| | - Zahra Dehghanfard
- Department of Cellular and Molecular Biology, Nourdanesh Institute of Higher Education, Isfahan 8351711111, Iran
| | | | - Maryam Firoozi
- Department of Medical Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran 14965/161, Iran
| | - Fatemeh Ahmadipour
- Pharmacy Department, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Goh Yong Meng
- Department of Preclinical Sciences, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Selangor 43400, Malaysia
| | - Massoud Houshmand
- Department of Medical Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran 14965/161, Iran
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Peterson A, Xia Z, Chen G, Lazarus P. In vitro metabolism of exemestane by hepatic cytochrome P450s: impact of nonsynonymous polymorphisms on formation of the active metabolite 17 β-dihydroexemestane. Pharmacol Res Perspect 2017; 5:e00314. [PMID: 28603633 PMCID: PMC5464343 DOI: 10.1002/prp2.314] [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: 03/21/2017] [Accepted: 03/24/2017] [Indexed: 11/29/2022] Open
Abstract
Exemestane (EXE) is an endocrine therapy commonly used by postmenopausal women with hormone‐responsive breast cancer due to its potency in inhibiting aromatase‐catalyzed estrogen synthesis. Preliminary in vitro studies sought to identify phase I EXE metabolites and hepatic cytochrome P450s (CYP450s) that participate in EXE biotransformation. Phase I metabolites were identified by incubating EXE with HEK293‐overexpressed CYP450s. CYP450s 1A2, 2C8, 2C9, 2C19, 2D6, 3A4, and 3A5 produce 17β‐dihydroexemestane (17β‐DHE), an active major metabolite, as well as two inactive metabolites. 17β‐DHE formation in pooled human liver microsomes subjected to isoform‐specific CYP450 inhibition was also monitored using tandem mass spectrometry. 17β‐DHE production in human liver microsomes was unaffected by isoform‐specific inhibition of CYP450s 2A6, 2B6, and 2E1 but decreased 12–39% following inhibition of drug‐metabolizing enzymes from CYP450 subfamilies 1A, 2C, 2D, and 3A. These results suggest that redundancy exists in the EXE metabolic pathway with multiple hepatic CYP450s catalyzing 17β‐DHE formation in vitro. To further expand the knowledge of phase I EXE metabolism, the impact of CYP450 genetic variation on 17β‐DHE formation was assessed via enzyme kinetic parameters. Affinity for EXE substrate and enzyme catalytic velocity were calculated for hepatic wild‐type CYP450s and their common nonsynonymous variants by monitoring the reduction of EXE to 17β‐DHE. Several functional polymorphisms in xenobiotic‐metabolizing CYP450s 1A2, 2C8, 2C9, and 2D6 resulted in deviant enzymatic activity relative to wild‐type enzyme. Thus, it is possible that functional polymorphisms in EXE‐metabolizing CYP450s contribute to inter‐individual variability in patient outcomes by mediating overall exposure to the drug and its active metabolite, 17β‐DHE.
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Affiliation(s)
- Amity Peterson
- Department of Pharmaceutical Sciences Washington State University Spokane Washington
| | - Zuping Xia
- Department of Pharmaceutical Sciences Washington State University Spokane Washington
| | - Gang Chen
- Department of Pharmaceutical Sciences Washington State University Spokane Washington
| | - Philip Lazarus
- Department of Pharmaceutical Sciences Washington State University Spokane Washington
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11
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Pharmacodynamic and cytogenetic evaluation in CYP2C19*2 and CYP2C19*3 allelomorphism in South Indian population with clopidogrel therapy. Int J Cardiol 2017; 229:113-118. [DOI: 10.1016/j.ijcard.2016.11.217] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 11/07/2016] [Indexed: 01/10/2023]
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12
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Ang GY, Yu CY, Subramaniam V, Abdul Khalid MIH, Tuan Abdu Aziz TA, Johari James R, Ahmad A, Abdul Rahman T, Mohd Nor F, Ismail AI, Md. Isa K, Salleh H, Teh LK, Salleh MZ. Detection of CYP2C19 Genetic Variants in Malaysian Orang Asli from Massively Parallel Sequencing Data. PLoS One 2016; 11:e0164169. [PMID: 27798644 PMCID: PMC5087908 DOI: 10.1371/journal.pone.0164169] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 09/21/2016] [Indexed: 12/11/2022] Open
Abstract
The human cytochrome P450 (CYP) is a superfamily of enzymes that have been a focus in research for decades due to their prominent role in drug metabolism. CYP2C is one of the major subfamilies which metabolize more than 10% of all clinically used drugs. In the context of CYP2C19, several key genetic variations that alter the enzyme’s activity have been identified and catalogued in the CYP allele nomenclature database. In this study, we investigated the presence of well-established variants as well as novel polymorphisms in the CYP2C19 gene of 62 Orang Asli from the Peninsular Malaysia. A total of 449 genetic variants were detected including 70 novel polymorphisms; 417 SNPs were located in introns, 23 in upstream, 7 in exons, and 2 in downstream regions. Five alleles and seven genotypes were inferred based on the polymorphisms that were found. Null alleles that were observed include CYP2C19*3 (6.5%), *2 (5.7%) and *35 (2.4%) whereas allele with increased function *17 was detected at a frequency of 4.8%. The normal metabolizer genotype was the most predominant (66.1%), followed by intermediate metabolizer (19.4%), rapid metabolizer (9.7%) and poor metabolizer (4.8%) genotypes. Findings from this study provide further insights into the CYP2C19 genetic profile of the Orang Asli as previously unreported variant alleles were detected through the use of massively parallel sequencing technology platform. The systematic and comprehensive analysis of CYP2C19 will allow uncharacterized variants that are present in the Orang Asli to be included in the genotyping panel in the future.
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Affiliation(s)
- Geik Yong Ang
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
| | - Choo Yee Yu
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
| | - Vinothini Subramaniam
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
| | - Mohd Ikhmal Hanif Abdul Khalid
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
| | - Tuan Azlin Tuan Abdu Aziz
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
| | - Richard Johari James
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
- Faculty of Pharmacy, Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
| | - Aminuddin Ahmad
- Faculty of Medicine, Universiti Teknologi MARA Selangor (UiTM), Sungai Buloh, Selangor, Malaysia
| | - Thuhairah Abdul Rahman
- Faculty of Medicine, Universiti Teknologi MARA Selangor (UiTM), Sungai Buloh, Selangor, Malaysia
| | - Fadzilah Mohd Nor
- Faculty of Medicine, Universiti Teknologi MARA Selangor (UiTM), Sungai Buloh, Selangor, Malaysia
| | - Adzrool Idzwan Ismail
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
- College of Arts and Sciences, Universiti Utara Malaysia (UUM), Sintok, Kedah, Malaysia
| | - Kamarudzaman Md. Isa
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
- Faculty of Communication and Media, University Selangor, Shah Alam, Selangor, Malaysia
| | - Hood Salleh
- Institut Alam Sekitar dan Pembangunan (LESTARI), Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia
| | - Lay Kek Teh
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
- Faculty of Pharmacy, Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
- * E-mail: (MZS); (LKT)
| | - Mohd Zaki Salleh
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
- Faculty of Pharmacy, Universiti Teknologi MARA Selangor (UiTM), Puncak Alam, Selangor, Malaysia
- * E-mail: (MZS); (LKT)
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13
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Isvoran A, Louet M, Vladoiu DL, Craciun D, Loriot MA, Villoutreix BO, Miteva MA. Pharmacogenomics of the cytochrome P450 2C family: impacts of amino acid variations on drug metabolism. Drug Discov Today 2016; 22:366-376. [PMID: 27693711 DOI: 10.1016/j.drudis.2016.09.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 07/22/2016] [Accepted: 09/20/2016] [Indexed: 12/18/2022]
Abstract
Pharmacogenomics investigates DNA and RNA variations in the human genome related to drug responses. Cytochrome P450 (CYP) is a supergene family of drug-metabolizing enzymes responsible for the metabolism of approximately 90% of human drugs. Among the major CYP isoforms, the CYP2C subfamily is of clinical significance because it metabolizes approximately 20% of clinically administrated drugs and represents several variant alleles leading to adverse drug reactions or altering drug efficacy. Here, we review recent progress on understanding the interindividual variability of the CYP2C members and the functional and clinical impact on drug metabolism. We summarize current advances in the molecular modeling of CYP2C polymorphisms and discuss the structural bases and molecular mechanisms of amino acid variants of CYP2C members that affect drug metabolism.
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Affiliation(s)
- Adriana Isvoran
- Department of Biology and Chemistry, West University of Timisoara, 16 Pestalozzi, Timisoara 300115, Romania; Advanced Environmental Research Laboratories, West University of Timisoara, 4 Oituz, Timisoara 300086, Romania
| | - Maxime Louet
- Université Paris Diderot, Sorbonne Paris Cité, Inserm UMR-S 973, Molécules Thérapeutiques In silico, 39 rue Helene Brion, 75013 Paris, France; INSERM, U973, Paris, France
| | - Diana Larisa Vladoiu
- Department of Biology and Chemistry, West University of Timisoara, 16 Pestalozzi, Timisoara 300115, Romania; Advanced Environmental Research Laboratories, West University of Timisoara, 4 Oituz, Timisoara 300086, Romania
| | - Dana Craciun
- Teacher Training Department, West University of Timisoara, Blvd. V. Parvan, Timisoara 300223, Romania
| | - Marie-Anne Loriot
- INSERM UMR_S1147, Centre Universitaire des Saints-Pères, 45 rue des saints-Pères, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Assistance Publique - Hôpitaux de Paris (AP-HP), Hôpital Européen Georges Pompidou, Service de Biochimie, 20 rue Leblanc, 75015 Paris, France
| | - Bruno O Villoutreix
- Université Paris Diderot, Sorbonne Paris Cité, Inserm UMR-S 973, Molécules Thérapeutiques In silico, 39 rue Helene Brion, 75013 Paris, France; INSERM, U973, Paris, France
| | - Maria A Miteva
- Université Paris Diderot, Sorbonne Paris Cité, Inserm UMR-S 973, Molécules Thérapeutiques In silico, 39 rue Helene Brion, 75013 Paris, France; INSERM, U973, Paris, France.
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14
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Hoh BL, Gong Y, McDonough CW, Waters MF, Royster AJ, Sheehan TO, Burkley B, Langaee TY, Mocco J, Zuckerman SL, Mummareddy N, Stephens ML, Ingram C, Shaffer CM, Denny JC, Brilliant MH, Kitchner TE, Linneman JG, Roden DM, Johnson JA. CYP2C19 and CES1 polymorphisms and efficacy of clopidogrel and aspirin dual antiplatelet therapy in patients with symptomatic intracranial atherosclerotic disease. J Neurosurg 2015; 124:1746-51. [PMID: 26587656 DOI: 10.3171/2015.6.jns15795] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Symptomatic intracranial atherosclerotic disease (ICAD) has a high risk of recurrent stroke. Genetic polymorphisms in CYP2C19 and CES1 are associated with adverse outcomes in cardiovascular patients, but have not been studied in ICAD. The authors studied CYP2C19 and CES1 single-nucleotide polymorphisms (SNPs) in symptomatic ICAD patients. METHODS Genotype testing for CYP2C19*2, (*)3, (*)8, (*)17 and CES1 G143E was performed on 188 adult symptomatic ICAD patients from 3 medical centers who were medically managed with clopidogrel and aspirin. Testing was performed prospectively at 1 center, and retrospectively from a DNA sample biorepository at 2 centers. Multiple logistic regression and Cox regression analysis were performed to assess the association of these SNPs with the primary endpoint, which was a composite of transient ischemic attack (TIA), stroke, myocardial infarction, or death within 12 months. RESULTS The primary endpoint occurred in 14.9% of the 188 cases. In multiple logistic regression analysis, the presence of the CYP2C19 loss of function (LOF) alleles *2, *3, and *8 in the medically managed patients was associated with lower odds of primary endpoint compared with wild-type homozygotes (odds ratio [OR] 0.13, 95% CI 0.03-0.62, p = 0.0101). Cox regression analysis demonstrated the CYP2C19 LOF carriers had a lower risk for the primary endpoint, with hazard ratio (HR) of 0.27 (95% CI 0.08-0.95), p = 0.041. A sensitivity analysis of a secondary composite endpoint of TIA, stroke, or death demonstrated a significant trend in multiple logistic regression analysis of CYP2C19 variants, with lower odds of secondary endpoint in patients carrying at least 1 LOF allele (*2, *3, *8) than in wild-type homozygotes (OR 0.27, 95% CI 0.06-1.16, p = 0.078). Cox regression analysis demonstrated that the carriers of CYP2C19 LOF alleles had a lower risk forthe secondary composite endpoint (HR 0.22, 95% CI 0.05-1.04, p = 0.056). CONCLUSIONS This is the first study examining genetic variants and their effects in symptomatic ICAD. Variant alleles of CYP2C19 (*2, *3, *8) were associated with lower odds of the primary and secondary composite endpoints. However, the direction of the association was opposite of what is expected based on this SNP. This may reflect an incomplete understanding of this genetic variation and its effect in symptomatic ICAD and warrants further investigations.
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Affiliation(s)
| | - Yan Gong
- Department of Pharmacotherapy and Translational Research and Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida; and
| | - Caitrin W McDonough
- Department of Pharmacotherapy and Translational Research and Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida; and
| | | | | | | | - Ben Burkley
- Department of Pharmacotherapy and Translational Research and Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida; and
| | - Taimour Y Langaee
- Department of Pharmacotherapy and Translational Research and Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida; and
| | - J Mocco
- Departments of 4 Neurosurgery
| | | | | | | | | | | | | | | | | | - James G Linneman
- Biomedical Informatics Research Center, Marshfield Clinic Research Foundation, Marshfield, Wisconsin
| | - Dan M Roden
- Medicine, and.,Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, and
| | - Julie A Johnson
- Division of Cardiovascular Medicine, College of Medicine, and.,Department of Pharmacotherapy and Translational Research and Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida; and
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15
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Jin T, Zhang M, Yang H, Geng T, Zhang N, Feng T, Ma Y, Yuan D, Kang L. Genetic polymorphisms of the drug-metabolizing enzymeCYP2C19in the Uyghur population in northwest China. Xenobiotica 2015; 46:634-640. [DOI: 10.3109/00498254.2015.1102986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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16
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Interindividual variability of CYP2C19-catalyzed drug metabolism due to differences in gene diplotypes and cytochrome P450 oxidoreductase content. THE PHARMACOGENOMICS JOURNAL 2015; 16:375-87. [PMID: 26323597 PMCID: PMC4775436 DOI: 10.1038/tpj.2015.58] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 05/19/2015] [Accepted: 06/23/2015] [Indexed: 02/01/2023]
Abstract
Large interindividual variability has been observed in the metabolism of CYP2C19 substrates in vivo. The study aimed to evaluate sources of this variability in CYP2C19 activity, focusing on CYP2C19 diplotypes and the cytochrome P450 oxidoreductase (POR). CYP2C19 gene analysis was carried out on 347 human liver samples. CYP2C19 activity assayed using human liver microsomes confirmed a significant a priori predicted rank order for (S)-mephenytoin hydroxylase activity of CYP2C19*17/*17 > *1B/*17 > *1B/*1B > *2A/*17 > *1B/*2A > *2A/*2A diplotypes. In a multivariate analysis, the CYP2C19*2A allele and POR protein content were associated with CYP2C19 activity. Further analysis indicated a strong effect of the CYP2C19*2A, but not the *17, allele on both metabolic steps in the conversion of clopidogrel to its active metabolite. The present study demonstrates that interindividual variability in CYP2C19 activity is due to differences in both CYP2C19 protein content associated with gene diplotypes and the POR concentration.
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17
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Dodgen TM, Drögemöller BI, Wright GEB, Warnich L, Steffens FE, Cromarty AD, Alessandrini M, Pepper MS. Evaluation of predictive CYP2C19 genotyping assays relative to measured phenotype in a South African cohort. Pharmacogenomics 2015; 16:1343-54. [PMID: 26244421 DOI: 10.2217/pgs.15.80] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
AIM To align predicted and measured CYP2C19 phenotype in a South African cohort. MATERIALS & METHODS Genotyping of CYP2C19*2, *3, *9, *15, *17, *27 and *28 was performed using PCR-RFLP, and an activity score (AS) system was used to predict phenotype. True phenotype was measured using plasma concentrations of omeprazole and its metabolite 5'-hydroxyomperazole. RESULTS Partial genotype-phenotype discrepancies were reported, and an adapted AS system was developed, which showed a marked improvement in phenotype prediction. Results highlight the need for a more comprehensive CYP2C19 genotyping approach to improve prediction of omeprazole metabolism. CONCLUSION Evidence for the utility of a CYP2C19 AS system is provided, for which the accuracy can be further improved by means of comprehensive genotyping and substrate-specific modification.
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Affiliation(s)
- Tyren M Dodgen
- Department of Pharmacology, University of Pretoria, Pretoria, South Africa.,Department of Immunology, Faculty of Health Sciences, University of Pretoria, PO Box 2034, Pretoria 0001, South Africa.,Institute for Cellular & Molecular Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Britt I Drögemöller
- Department of Genetics, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Galen E B Wright
- Department of Genetics, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Louise Warnich
- Department of Genetics, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Francois E Steffens
- Department of Statistics, Faculty of Natural & Agricultural Sciences, University of Pretoria, Pretoria, South Africa
| | - A Duncan Cromarty
- Department of Pharmacology, University of Pretoria, Pretoria, South Africa
| | - Marco Alessandrini
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, PO Box 2034, Pretoria 0001, South Africa.,Institute for Cellular & Molecular Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Michael S Pepper
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, PO Box 2034, Pretoria 0001, South Africa.,Institute for Cellular & Molecular Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.,Department of Genetic Medicine & Development, Faculty of Medicine, University of Geneva, Switzerland
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18
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Skierka JM, Black JL. Analysis of compound heterozygous CYP2C19 genotypes to determine cis and trans configurations. Pharmacogenomics 2015; 15:1197-205. [PMID: 25141895 DOI: 10.2217/pgs.14.72] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Through allele specific PCR we studied 220 CYP2C19 compound heterozygous samples, of unknown ethnicity, to determine the haplotype for each of the variations within a sample. MATERIALS & METHODS The genotypes assessed were: 180 *2 and *17 samples (100% in trans); 20 *2 and *11 samples (100% in cis); ten *4 and *17 samples (50% of the samples were *1/*4B and 50% *4A/*17); six *2, *11 and *17 samples (100% showed *2 and *11 in cis, and *17 in trans); two *2, *4 and *17 samples (100% *4B with *2 in trans); one sample with *17 and *34 (these were in trans); and one sample that contained *2, *17, c.463G>T (p.E155X; *17 and c.463G>T were in cis, with *2 in trans). RESULTS & CONCLUSION In our study, we observed a different frequency for the *4B allele (when a sample contains both *4 and *17); and identified *17 occurring in cis with a novel nonsense allele. Accurately assessing a patient's genotype, including assignment of a haplotype, can be important when making a phenotype prediction.
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Affiliation(s)
- Jennifer M Skierka
- Personalized Genomics Laboratory, Department of Laboratory Medicine & Pathology, Mayo Clinic & Mayo Medical School, 200 First St SW, Rochester, MN 55905, USA
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19
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Chua EW, Miller AL, Kennedy MA. Choice of PCR microtube can impact on the success of long-range PCRs. Anal Biochem 2015; 477:115-7. [DOI: 10.1016/j.ab.2015.02.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 02/19/2015] [Accepted: 02/19/2015] [Indexed: 10/23/2022]
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20
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Therapeutic drug monitoring for triazoles: A needs assessment review and recommendations from a Canadian perspective. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2015; 25:327-43. [PMID: 25587296 PMCID: PMC4277162 DOI: 10.1155/2014/340586] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Invasive fungal infections cause significant morbidity and mortality in patients with concomitant underlying immunosuppressive diseases. The recent addition of new triazoles to the antifungal armamentarium has allowed for extended-spectrum activity and flexibility of administration. Over the years, clinical use has raised concerns about the degree of drug exposure following standard approved drug dosing, questioning the need for therapeutic drug monitoring (TDM). Accordingly, the present guidelines focus on TDM of triazole antifungal agents. A review of the rationale for triazole TDM, the targeted patient populations and available laboratory methods, as well as practical recommendations based on current evidence from an extended literature review are provided in the present document.
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Abstract
Cytochrome 450 (CYP450) designates a group of enzymes abundant in smooth endoplasmic reticulum of hepatocytes and epithelial cells of small intestines. The main function of CYP450 is oxidative catalysis of various endogenous and exogenous substances. CYP450 are implicated in phase I metabolism of 80% of drugs currently in use, including anticancer drugs. They are also involved in synthesis of various hormones and influence hormone-related cancers. CYP450 genes are highly polymorphic and their variants play an important role in cancer risk and treatment. Association studies and meta-analyses have been performed to decipher the role of CYP450 polymorphisms in cancer susceptibility. Cancer treatment involves multimodal therapies and evaluation of CYP450 polymorphisms is necessary for pharmacogenetic assessment of anticancer therapy outcomes. In addition, CYP450 inhibitors are being evaluated for improved pharmacokinetics and oral formulation of several anticancer drugs.
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Kumar Y, Kung S, Shinozaki G. CYP2C19 variation, not citalopram dose nor serum level, is associated with QTc prolongation. J Psychopharmacol 2014; 28:1143-8. [PMID: 25122046 DOI: 10.1177/0269881114543720] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recently, a FDA Safety Communication warned of a dose-dependent risk for QTc prolongation with citalopram, which is metabolized by CYP2C19 of the cytochrome P450 system. We investigate associations between citalopram and escitalopram dose, serum concentration, CYP2C19 phenotype, and QTc. We undertook a retrospective chart review of citalopram or escitalopram patients with the inclusion criteria of consistent medication dose, CYP2C19 phenotype (extensive metabolizers [EM], intermediate metabolizers [IM], poor metabolizers [PM]), and QTc interval on ECG. We further identified 42 citalopram users with citalopram serum concentration measurements and ECG. Regression and one-way ANOVA were used to examine the relationship between citalopram dose, citalopram serum concentration, CYP2C19 phenotype, and QTc interval. Of 75 citalopram patients, the EM group had significantly shorter QTc intervals than a combined IM+PM group (427.1±23.6 ms vs. 440.1±26.6 ms, one-tailed t-test, p=0.029). In the 80 escitalopram cohort, there was no significant difference in QTc between phenotype groups. There was no statistical correlation between citalopram (p=0.62) or escitalopram (p=0.30) dose and QTc. QTc was not associated with citalopram serum level (p=0.45). In contrast to the FDA warning, this study found no association between citalopram/escitalopram dose and QTc. However, PM of the drug tended to have longer QTc intervals. Our findings suggest cytochrome P450 genotyping in select patients may be helpful to guide medication optimization while limiting harmful effects.
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Affiliation(s)
| | - Simon Kung
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN, USA
| | - Gen Shinozaki
- Department of Psychiatry, University of Iowa, Iowa City, IA, USA
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23
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The influence of the CYP2C19*10 allele on clopidogrel activation and CYP2C19*2 genotyping. Pharmacogenet Genomics 2014; 24:381-6. [PMID: 24945780 DOI: 10.1097/fpc.0000000000000068] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND/OBJECTIVES The polymorphic hepatic enzyme CYP2C19 catalyzes the metabolism of clinically important drugs such as clopidogrel, proton-pump inhibitors, and others and clinical pharmacogenetic testing for clopidogrel is increasingly common. The CYP2C19*10 single-nucleotide polymorphism (SNP) is located 1 bp upstream the CYP2C19*2 SNP. Despite the low frequency of the CYP2C19*10 allele, its impact on metabolism of CYP2C19 substrates and CYP2C19*2 genotyping makes it an important SNP to consider for pharmacogenetic testing of CYP2C19. However, the effect of the CYP2C19*10 allele on clopidogrel metabolism has not been explored to date. METHODS We measured the enzymatic activity of the CYP2C19.10 protein against clopidogrel. DNA samples from two clinical studies were genotyped for CYP2C19*2 and *10 by pyrosequencing genotyping method. RESULTS The catalytic activity of CYP2C19.10 in the biotransformation of clopidogrel and 2-oxo-clopidogrel was significantly decreased relative to the wild-type CYP2C19.1B. We also reported that the CYP2C19*10 SNP interferes with the CYP2C19*2 TaqMan genotyping assay, resulting in miscalling of CYP2C19*10/*2 as CYP2C19*2/*2. CONCLUSIONS Our data provide evidence that CYP2C19.10 variant partially metabolizes clopidogrel and 2-oxo-clopidogrel, and the presence of CYP2C19*10 allele affects the CY2C19*2 TaqMan genotyping assay and results in misclassification of CYP2C19*10/*2 as CYP2C19*2/*2.
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Finkelman RD, Wang TD, Wang Y, Azumaya CT, Birmingham BK, Wissmar J, Mosqueda-Garcia R. Effect of CYP2C19 polymorphism on the pharmacokinetics of rosuvastatin in healthy Taiwanese subjects. Clin Pharmacol Drug Dev 2014; 4:33-40. [PMID: 27128002 DOI: 10.1002/cpdd.135] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 06/09/2014] [Indexed: 01/08/2023]
Abstract
CYP2C19 contributes to N-desmethyl rosuvastatin formation in "in vitro" models. Approximately 80% of Taiwanese are CYP2C19 extensive metabolizers (EMs, CYP2C19*1/*1, *1/*2, or *1/*3). We studied the potential effect of CYP2C19 genotypes on rosuvastatin pharmacokinetics in healthy Taiwanese subjects following single and multiple daily oral doses of rosuvastatin calcium (20 mg). Geometric mean ratios for poor metabolizers (PMs): EMs for rosuvastatin were 0.974 and 0.872 for area under the curve and maximum plasma concentration on day 1 (1.01 and 0.965 on day 17) and for N-desmethyl rosuvastatin, 1.21 and 1.07 on day 1 (1.14 and 1.09 on day 17), respectively. Changes of lipid profiles from baseline to day 18 for PMs and EMs were -52.4% and -53.3% (low-density lipoprotein cholesterol), and -34.2% and -30.0% (total cholesterol), respectively. Rosuvastatin was generally well-tolerated by both PMs and EMs. These results suggest that CYP2C19 polymorphism does not affect rosuvastatin pharmacokinetics in healthy Taiwanese in a clinically meaningful way.
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Affiliation(s)
| | - Tzung-Dau Wang
- Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, Taipei City, Taiwan
| | - Yi Wang
- Purdue Pharma, Stamford, CT, USA
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25
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Liu X, Hu L, Ge G, Yang B, Ning J, Sun S, Yang L, Pors K, Gu J. Quantitative analysis of cytochrome P450 isoforms in human liver microsomes by the combination of proteomics and chemical probe-based assay. Proteomics 2014; 14:1943-51. [DOI: 10.1002/pmic.201400025] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 05/21/2014] [Accepted: 06/05/2014] [Indexed: 01/31/2023]
Affiliation(s)
- Xidong Liu
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education; Jilin University; Changchun P.R. China
- Research Center for Drug Metabolism, School of Life Sciences; Jilin University; Changchun P.R. China
| | - Lianghai Hu
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education; Jilin University; Changchun P.R. China
- Research Center for Drug Metabolism, School of Life Sciences; Jilin University; Changchun P.R. China
| | - Guangbo Ge
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian P.R. China
| | - Bo Yang
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education; Jilin University; Changchun P.R. China
- Research Center for Drug Metabolism, School of Life Sciences; Jilin University; Changchun P.R. China
| | - Jing Ning
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian P.R. China
| | - Shixin Sun
- Asia Pacific Application Support Center; Applied Biosystems; Shanghai P.R. China
| | - Ling Yang
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian P.R. China
| | - Klaus Pors
- Institute of Cancer Therapeutics; School of Life Sciences; University of Bradford; West Yorkshire UK
| | - Jingkai Gu
- Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education; Jilin University; Changchun P.R. China
- Research Center for Drug Metabolism, School of Life Sciences; Jilin University; Changchun P.R. China
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Jeong HE, Lee SJ, Cha EY, Kim EY, Kim HS, Song YH, Shin JG. Development of a multiplex and cost-effective genotype test toward more personalized medicine for the antiplatelet drug clopidogrel. Int J Mol Sci 2014; 15:7699-710. [PMID: 24857912 PMCID: PMC4057700 DOI: 10.3390/ijms15057699] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 04/20/2014] [Accepted: 04/22/2014] [Indexed: 12/20/2022] Open
Abstract
There has been a wide range of inter-individual variations in platelet responses to clopidogrel. The variations in response to clopidogrel can be driven by genetic polymorphisms involved in the pathway of absorption, distribution, metabolism, excretion, and the target receptor P2Y12. A set of genetic variants known for causing variations in clopidogrel responses was selected, which included CYP2C19*2, *3, *17, CYP2B6*4, *6, *9, CYP3A4*18, CYP3A5*3, MDR1 2677G > T/A, 3435C > T, and P2Y12 H2 (742T > C). The simultaneous detection of these 10 variants was developed by using a multiplex PCR and single-base extension (MSSE) methodology. The newly developed genotyping test was confirmed by direct DNA sequencing in the representative positive control samples and validated in an extended set of 100 healthy Korean subjects. Genotyping results from the developed MSSE exhibited a perfect concordance with the direct DNA sequencing data and all of variants tested in 100 healthy Korean subjects were in agreement with Hardy-Weinberg equilibrium (p > 0.05). The present molecular diagnostic studies provide an accurate, convenient, and fast genotyping method for the detection of multiple variants. This would be helpful for researchers, as well as clinicians, to use genetic information toward more personalized medicine of clopidogrel and other antiplatelet drugs in the future.
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Affiliation(s)
- Hye-Eun Jeong
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, Busan 614-812, Korea.
| | - Su-Jun Lee
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, Busan 614-812, Korea.
| | - Eun-Young Cha
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, Busan 614-812, Korea.
| | - Eun-Young Kim
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, Busan 614-812, Korea.
| | - Ho-Sook Kim
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, Busan 614-812, Korea.
| | - Young Hwan Song
- Department of Microbiology, Pukyoung National University, Busan 608-737, Korea.
| | - Jae-Gook Shin
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, Busan 614-812, Korea.
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Martiny VY, Miteva MA. Advances in molecular modeling of human cytochrome P450 polymorphism. J Mol Biol 2013; 425:3978-92. [PMID: 23856621 DOI: 10.1016/j.jmb.2013.07.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 07/01/2013] [Accepted: 07/02/2013] [Indexed: 01/08/2023]
Abstract
Cytochrome P450 (CYP) is a supergene family of metabolizing enzymes involved in the phase I metabolism of drugs and endogenous compounds. CYP oxidation often leads to inactive drug metabolites or to highly toxic or carcinogenic metabolites involved in adverse drug reactions (ADR). During the last decade, the impact of CYP polymorphism in various drug responses and ADR has been demonstrated. Of the drugs involved in ADR, 56% are metabolized by polymorphic phase I metabolizing enzymes, 86% among them being CYP. Here, we review the major CYP polymorphic forms, their impact for drug response and current advances in molecular modeling of CYP polymorphism. We focus on recent studies exploring CYP polymorphism performed by the use of sequence-based and/or protein-structure-based computational approaches. The importance of understanding the molecular mechanisms related to CYP polymorphism and drug response at the atomic level is outlined.
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Affiliation(s)
- Virginie Y Martiny
- Université Paris Diderot, Sorbonne Paris Cité, Molécules Thérapeutiques In Silico, Inserm UMR-S 973, 35 rue Helene Brion, 75013 Paris, France; Inserm, U973, F-75205 Paris, France
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Sanford JC, Guo Y, Sadee W, Wang D. Regulatory polymorphisms in CYP2C19 affecting hepatic expression. ACTA ACUST UNITED AC 2013; 28:23-30. [PMID: 23412869 DOI: 10.1515/dmdi-2012-0038] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 01/03/2013] [Indexed: 11/15/2022]
Abstract
BACKGROUND Cytochrome P450 2C19 is responsible for the metabolism of many drugs, including the activation of clopidogrel. The allele CYP2C19*17 is associated with ultra-rapid metabolizer phenotypes by increasing gene transcription. This study tests to what extent CYP2C19*17 enhances CYP2C19 expression in human liver and whether additional regulatory variants contribute to variation in CYP2C19 expression. METHODS CYP2C19 mRNA was measured with quantitative real-time PCR (qRT-PCR), enzyme activity as metabolic velocity with S-mephenytoin as the substrate and allelic mRNA expression ratio with SNaPshot in human livers. CYP2C19 transcribed exons and a 4kb promoter region were sequenced using IonTorrent PGM or Sanger sequencing and screened for polymorphisms associated with total hepatic CYP2C19 mRNA, enzyme activity and allelic mRNA ratios. RESULTS Livers heterozygote and homozygous for CYP2C19*17 had mRNA levels 1.8-fold (p=0.028) and 2.9-fold (p=0.006), respectively, above homozygous reference allele livers. CYP2C19*17 heterozygotes were also associated with increased allelic mRNA expression (allelic ratio ~1.8-fold, SD±0.6, p<0.005), whereas CYP2C19 enzyme activity was elevated 2.3-fold, with borderline significance (p=0.06) in CYP2C19*17 carriers. One liver sample of African ancestry displayed a 2-fold allelic expression ratio, and another sample, a ~12-fold increase in metabolic velocity. Neither case was accounted for by *17, which indicates the presence of additional regulatory variants. CONCLUSIONS Our findings confirm *17 as a regulatory polymorphism enhancing hepatic CYP2C19 expression 2-fold with potential to compensate for the loss of function allele CYP2C19*2. Additional regulatory factors may also enhance CYP2C19 expression in African American populations.
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Comparison of High Loading Dose Versus Usual Dose of Rectal Acetaminophen in the Treatment of Febrile Children. ARCHIVES OF PEDIATRIC INFECTIOUS DISEASES 2013. [DOI: 10.5812/pedinfect.10350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Alessandrini M, Asfaha S, Dodgen TM, Warnich L, Pepper MS. Cytochrome P450 pharmacogenetics in African populations. Drug Metab Rev 2013; 45:253-75. [PMID: 23590174 DOI: 10.3109/03602532.2013.783062] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The Cytochrome P450 (CYP450) family of enzymes is involved in the oxidative metabolism of many therapeutic drugs, carcinogens and various endogenous substrates. These enzymes are highly polymorphic at an inter-individual and inter-ethnic level. Polymorphisms or genetic variations account for up to 30% of inter-individual differences seen in a variety of drug responses. The frequencies of the different metabolizer categories (slow, intermediate, extensive and ultra-rapid), the distribution of genetic variants, genotype-phenotype correlations and the clinical importance of the CYP450 enzymes have been extensively documented in Caucasian and Oriental populations. Limited data exists for African populations, despite the fact that this knowledge is critically important for these populations who experience a heavy burden of communicable and non-communicable diseases. In addition, the costs incurred through adverse drug reactions and non-responsiveness to therapy could be reduced through the wide-scale application of pharmacogenetics. This review provides an overview and investigation of CYP450 genotypic and phenotypic reports published from 1980 to present in African populations. Our findings confirm the high degree of variability that is expected when comparing individuals of African origin to other ethnic groups and also highlight the distribution of clinically relevant CYP450 alleles amongst the various African populations. The notable discordance in genotypic and phenotypic data amongst African populations exemplifies the need for in-depth and well-orchestrated molecular and pharmacological investigations of these populations in the future, for which whole genome sequencing and association studies will be critical.
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Affiliation(s)
- Marco Alessandrini
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
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Liu G, Lao R, Xu L, Xu Q, Li L, Zhang M, Song S, Fan C. Single-nucleotide polymorphism genotyping using a novel multiplexed electrochemical biosensor with nonfoulingsurface. Biosens Bioelectron 2013; 42:516-21. [DOI: 10.1016/j.bios.2012.11.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 10/23/2012] [Accepted: 11/06/2012] [Indexed: 10/27/2022]
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Reynald RL, Sansen S, Stout CD, Johnson EF. Structural characterization of human cytochrome P450 2C19: active site differences between P450s 2C8, 2C9, and 2C19. J Biol Chem 2012; 287:44581-91. [PMID: 23118231 DOI: 10.1074/jbc.m112.424895] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
To identify the structural features underlying the distinct substrate and inhibitor profiles of P450 2C19 relative to the closely related human enzymes, P450s 2C8 and 2C9, the atomic structure (Protein Data Bank code 4GQS) of cytochrome P450 2C19 complexed with the inhibitor (2-methyl-1-benzofuran-3-yl)-(4-hydroxy-3,5-dimethylphenyl)methanone (Protein Data Bank chemical component 0XV) was determined to 2.87 Å resolution by x-ray crystallography. The conformation of the peptide backbone of P450 2C19 is most similar to that of P450 2C8, but the substrate-binding cavity of P450 2C8 is much larger than that of P450 2C19 due to differences in the amino acid residues that form the substrate-binding cavities of the two enzymes. In contrast, the substrate-binding cavity of P450 2C19 is much more similar in size to that of the structure of the P450 2C9 flurbiprofen complex than to that of a modified P450 2C9 or that of P450 2C8. The cavities of the P450 2C19 0XV complex and the P450 2C9 flurbiprofen complex differ, however, because the helix B-C loops of the two enzymes are dissimilar. These conformational differences reflect the effects of adjacent structural elements that interact with the B-C loops and that differ between the two enzymes. The availability of a structure for 2C19 will facilitate computational approaches for predictions of substrate and inhibitor binding to this enzyme.
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Affiliation(s)
- R Leila Reynald
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
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33
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Helsby NA, Burns KE. Molecular mechanisms of genetic variation and transcriptional regulation of CYP2C19. Front Genet 2012; 3:206. [PMID: 23087703 PMCID: PMC3467616 DOI: 10.3389/fgene.2012.00206] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 09/24/2012] [Indexed: 12/11/2022] Open
Abstract
Inherited variation in the function of the drug metabolizing enzyme CYP2C19 was first observed 40 years ago. The SNP variants which underpin loss of CYP2C19 function have been elucidated and extensively studied in healthy populations. However, there has been relatively meagre translation of this information into the clinic. The presence of genotype-phenotype discordance in certain patients suggests that changes in the regulation of this gene, as well as loss of function SNPs, could play a role in deficient activity of this enzyme. Knowledge of the molecular mechanisms which control transcription of this gene, reviewed in this article, may aid the challenge of delivering CYP2C19 pharmacogenetics into clinical use.
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Affiliation(s)
- Nuala Ann Helsby
- Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland Auckland, New Zealand
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PharmGKB summary: very important pharmacogene information for cytochrome P450, family 2, subfamily C, polypeptide 19. Pharmacogenet Genomics 2012; 22:159-65. [PMID: 22027650 DOI: 10.1097/fpc.0b013e32834d4962] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Relative Copy Number Variations of CYP2C19 in South Indian Population. Mol Biol Int 2012; 2012:643856. [PMID: 22792463 PMCID: PMC3389726 DOI: 10.1155/2012/643856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 04/28/2012] [Indexed: 01/19/2023] Open
Abstract
CYP2C19 is a polymorphic enzyme involved in the metabolism of clinically important drugs. Genotype-phenotype association studies of CYP2C19 have reported wide ranges in the metabolic ratios of its substrates. These discrepancies could be attributed to the variations in the promoter region and this aspect has been reported recently. The observations in the recent reports on the influence of promoter region variants on the metabolism of CYP2C19 substrates might also have been influenced by the copy number variations of CYP2C19. In this paper, we describe copy number variations of CYP2C19 using real-time polymerase chain reaction by comparative Ct method. No copy number variations were observed in the south Indian population indicating the observed discrepancies in genotype-phenotype association studies might be due to the regulatory region polymorphisms as reported earlier.
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Abstract
The purpose of this review is to discuss the clinical application of pharmacogenomics for select drug therapies (eg, proton pump inhibitors [PPIs], codeine, and carbamazepine) and to highlight limitations and challenges that preclude implementation of pharmacogenomics into clinical practice. Genetic polymorphisms of cytochrome P450 (CYP) enzymes and the presence of the human leukocyte antigen ( HLA) -B*1502 allele influence drug disposition and/or response. A portion of PPI pharmacokinetic and pharmacodynamic variability can be explained by CYP2C19 genotype. However, conflicting evidence exists related to Helicobacter pylori cure rates based on CYP2C19 genotype. For codeine, adverse drug reactions in neonates through breast-feeding from CYP2D6 ultra-rapid metabolizers have been reported. However, there is lack of conclusive evidence regarding the overall influence of CYP2D6 polymorphisms on codeine efficacy and toxicity. Although CYP2C19 and CYP2D6 genotyping tests are available, clinical utility remains low. The presence of the HLA-B*1502 allele is associated with carbamazepine-induced Stevens-Johnson syndrome (SJS) and/or toxic epidermal necrolysis (TEN). Pharmacogenomic testing is required prior to initiating carbamazepine in high-risk patients. Lack of sufficient resources, provider knowledge, and ethical, legal, and social issues are several limitations and challenges to implementing pharmacogenomic testing in clinical practice.
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Affiliation(s)
- Joseph D. Ma
- Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Kelly C. Lee
- Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Grace M. Kuo
- Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
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Ramirez AH, Shi Y, Schildcrout JS, Delaney JT, Xu H, Oetjens MT, Zuvich RL, Basford MA, Bowton E, Jiang M, Speltz P, Zink R, Cowan J, Pulley JM, Ritchie MD, Masys DR, Roden DM, Crawford DC, Denny JC. Predicting warfarin dosage in European-Americans and African-Americans using DNA samples linked to an electronic health record. Pharmacogenomics 2012; 13:407-18. [PMID: 22329724 DOI: 10.2217/pgs.11.164] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
AIM Warfarin pharmacogenomic algorithms reduce dosing error, but perform poorly in non-European-Americans. Electronic health record (EHR) systems linked to biobanks may allow for pharmacogenomic analysis, but they have not yet been used for this purpose. PATIENTS & METHODS We used BioVU, the Vanderbilt EHR-linked DNA repository, to identify European-Americans (n = 1022) and African-Americans (n = 145) on stable warfarin therapy and evaluated the effect of 15 pharmacogenetic variants on stable warfarin dose. RESULTS Associations between variants in VKORC1, CYP2C9 and CYP4F2 with weekly dose were observed in European-Americans as well as additional variants in CYP2C9 and CALU in African-Americans. Compared with traditional 5 mg/day dosing, implementing the US FDA recommendations or the International Warfarin Pharmacogenomics Consortium (IWPC) algorithm reduced error in weekly dose in European-Americans (13.5-12.4 and 9.5 mg/week, respectively) but less so in African-Americans (15.2-15.0 and 13.8 mg/week, respectively). By further incorporating associated variants specific for European-Americans and African-Americans in an expanded algorithm, dose-prediction error reduced to 9.1 mg/week (95% CI: 8.4-9.6) in European-Americans and 12.4 mg/week (95% CI: 10.0-13.2) in African-Americans. The expanded algorithm explained 41 and 53% of dose variation in African-Americans and European-Americans, respectively, compared with 29 and 50%, respectively, for the IWPC algorithm. Implementing these predictions via dispensable pill regimens similarly reduced dosing error. CONCLUSION These results validate EHR-linked DNA biorepositories as real-world resources for pharmacogenomic validation and discovery.
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Affiliation(s)
- Andrea H Ramirez
- Department of Medicine, Vanderbilt University in Nashville, TN 37232, USA
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Ellison CA, Abou El-Ella SS, Tawfik M, Lein PJ, Olson JR. Allele and genotype frequencies of CYP2B6 and CYP2C19 polymorphisms in Egyptian agricultural workers. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2012; 75:232-241. [PMID: 22352331 PMCID: PMC3500531 DOI: 10.1080/15287394.2012.641201] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Genetic variability in cytochrome P-450 (CYP) has the potential to modify pharmacological and toxicological responses to many chemicals. Both CYP2B6 and CYP2C19 are pharmacologically and toxicologically relevant due to their ability to metabolize multiple drugs and environmental contaminants, including the organophosphorus (OP) pesticide chlorpyrifos. The aim of this study was to determine the prevalence of CYP2B6 and CYP2C19 variants in an indigenous Egyptian population (n = 120) that was shown to be occupationally exposed to chlorpyrifos. Further, the genotyping data was compared for Egyptians with previously studied populations to determine between population differences. Allelic frequencies were CYP2B6 1459C > T (3.8%), CYP2B6 785A > G (30.4%), CYP2B6 516G > T (28.8%), CYP2C19 681G > A (3.8%), and CYP2C19 431G > A (0%). The most prevalent CYP2B6 genotype combinations were CYP2B6 *1/*1 (44%), *1/*6 (38%), *6/*6 (8%), and *1/*5 (6%). The frequency of the CYP2C19 genotype combinations were CYP2C19 *1/*1 (93%), *1/*2 (6%), and *2/*2 (1%). The frequency of the CYP2B6 516G > T and CYP2B6 785A > G polymorphisms in this Egyptian cohort is similar to that found North American and European populations but significantly different from that reported for West African populations, while that of CYP2B6 1459C > T is similar to that found in Africans and African Americans. The observed frequency of CYP2C19 681G > A in Egyptians is similar to that of African pygmies but significantly different from other world populations, while CYP2C19 431 G > A was significantly different from that of African pygmies but similar to other world populations.
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Affiliation(s)
- Corie A Ellison
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York 14214, USA.
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Lee IS, Kim D. Polymorphic metabolism by functional alterations of human cytochrome P450 enzymes. Arch Pharm Res 2011; 34:1799-816. [PMID: 22139682 DOI: 10.1007/s12272-011-1103-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 08/24/2011] [Indexed: 10/14/2022]
Abstract
The study of cytochrome P450 pharmacogenomics is of particular interest because of its promise in the development of rational means to optimize drug therapy with respect to patient's genotype to ensure maximum efficacy with minimal adverse effects. Drug metabolizing P450 enzymes are polymorphic and are the main phase I enzymes responsible for the metabolism of clinical drugs. Therefore, polymorphisms in the P450s have the most impact on the fate of clinical drugs in phase I metabolism since almost 80% of drugs in use today are metabolized by these enzymes. Predictive genotyping for P450 enzymes for a more effective therapy will be routine for specific drugs in the future. In this review, we discuss the current knowledge of polymorphic metabolism by functional alterations in nonsynonymous SNPs of P450 1A2, 2A6, 2C8, 2C9, 2C19, 2D6, and 3A4 enzymes.
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Affiliation(s)
- Im-Soon Lee
- Department of Biological Sciences and Center for Biotechnology Research in UBITA, Konkuk University, Seoul 143-701, Korea
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Abstract
The cytochrome P450 (CYP) superfamily is one of the most important groups of enzymes involved in drug metabolism. It is responsible for the metabolism of a large number of drugs. Many CYP isoforms are expressed polymorphically, and catalytic alterations of allelic variant proteins can affect the metabolic activities of many drugs. The CYP2D6, CYP2C9, CYP2C19, and CYP2B6 genes are particularly polymorphic, whereas CYP1A1, CYP1A2, CYP2E1, and CYP3A4 are relatively well conserved without common functional polymorphisms. In vitro studies using cDNA expression systems are useful tools for evaluating functional alterations of the allelic variants of CYP, particularly for low-frequency alleles. Recombinant CYPs have been successfully expressed in bacteria, yeast, baculoviruses, and several mammalian cells. Determination of CYP variant-mediated kinetic parameters (Km and Vmax) in vitro can be useful for predicting drug dosing and clearance in humans. This review focuses on the advantages and disadvantages of the various cDNA-expression systems used to determine the kinetic parameters for CYP allelic variants, the methods for determining the kinetic parameters, and the findings of in vitro studies on highly polymorphic CYPs, including CYP2D6, CYP2C9, CYP2C19, and CYP2B6.
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Affiliation(s)
- Masahiro Hiratsuka
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
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Phan VH, Tan C, Rittau A, Xu H, McLachlan AJ, Clarke SJ. An update on ethnic differences in drug metabolism and toxicity from anti-cancer drugs. Expert Opin Drug Metab Toxicol 2011; 7:1395-410. [PMID: 21950349 DOI: 10.1517/17425255.2011.624513] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION Based on recent emerging evidence of inter-ethnic differences in drug response and toxicity, ethnic diversity in pharmacokinetics, pharmacogenomics and clinical outcomes are being increasingly investigated. Ultimately, this will promote improved understanding of inter-individual differences in the pharmacokinetics and tolerance of cytotoxic drugs. AREAS COVERED This article reviews potential explanations for the observed ethnic differences in treatment outcomes and provides clinical data to support this concept. A literature search was implemented on PubMed and PharmGKB to investigate the areas of ethnic differences in pharmacogenomics, pharmacogenetics and clinical outcomes of cancer therapies. EXPERT OPINION There has been a relative paucity of clinical evidence linking genetic polymorphisms of genes encoding drug-metabolizing enzymes to the pharmacokinetics, pharmacodynamics and tolerance of anti-cancer drugs. Future research should focus on studies using large sample sizes, in the hope that they will provide results of high clinical significance. Due to the potential for ethnic differences to impact on both toxicities and benefits of systemic cancer therapies, the development of new therapeutic agents should include patients from diverse geographical ancestries in each phase of drug development.
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Affiliation(s)
- Viet Hong Phan
- The University of Sydney, Concord Repatriation General Hospital, Sydney Cancer Centre, Concord, NSW, Sydney, Australia
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Wang H, Kim RA, Sun D, Gao Y, Wang H, Zhu J, Chen C. Evaluation of the effects of 18 non-synonymous single-nucleotide polymorphisms of CYP450 2C19 onin vitrodrug inhibition potential by a fluorescence-based high-throughput assay. Xenobiotica 2011; 41:826-35. [DOI: 10.3109/00498254.2011.582893] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Genetically Polymorphic Cytochrome P450s and Transporters and Personalized Antimicrobial Chemotherapy. Mol Microbiol 2011. [DOI: 10.1128/9781555816834.ch52] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Yin T, Miyata T. Pharmacogenomics of clopidogrel: evidence and perspectives. Thromb Res 2011; 128:307-16. [PMID: 21592545 DOI: 10.1016/j.thromres.2011.04.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Revised: 04/13/2011] [Accepted: 04/15/2011] [Indexed: 10/18/2022]
Abstract
Clopidogrel has become the mainstay oral antiplatelet regimen to prevent recurrent ischemic events after acute coronary syndromes or stent placement. However, there is marked interindividual variability in the antiplatelet effects of clopidogrel, and a reduced response to this drug may be a risk factor for ischemic complications. Pharmacogenomic analyses, including candidate-gene and genome-wide association studies, have confirmed that genetic polymorphisms in the hepatic cytochrome P450 (CYP) 2C19 dominantly affect the antiplatelet effects of clopidogrel. CYP2C19 reduced-function alleles have been associated with a significant decrease in clopidogrel responsiveness and a higher risk of adverse cardiac events including stent thrombosis, myocardial infarction, and death in several prospective studies, although these effects were not reproduced in a recent large randomized study that included a randomized control group. The US Food and Drug Administration addressed this issue by adding a boxed warning to the clopidogrel label and suggesting that adjusting the clopidogrel dose or using alternative antiplatelet agents should be potentially implemented for high-risk individuals who are identified based on the CYP2C19 genotype. Although it is promising that CYP2C19 genotyping could be used to guide personalized antiplatelet clopidogrel therapy, currently there is insufficient evidence to recommend routine genetic testing. Prospective randomized clinical trials are necessary to validate this pharmacogenomic approach to clopidogrel therapy. In the most recent trial, paraoxonase-1 (PON1) was identified as a crucial new enzyme for clopidogrel bioactivation, with its common Q192R polymorphism determining the rate of active metabolite and the clinical activity of clopidogrel. Further studies are needed to investigate the comprehensive influence of a number of different polymorphisms of CYP2C19 and PON1 variant alleles or other genetic variants on clopidogrel in various ethnic populations.
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Affiliation(s)
- Tong Yin
- Institute of Geriatric Cardiology, General Hospital of People's Liberation Army, Beijing, China
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Scott SA, Martis S, Peter I, Kasai Y, Kornreich R, Desnick RJ. Identification of CYP2C19*4B: pharmacogenetic implications for drug metabolism including clopidogrel responsiveness. THE PHARMACOGENOMICS JOURNAL 2011; 12:297-305. [PMID: 21358751 DOI: 10.1038/tpj.2011.5] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CYP2C19 is a principal enzyme involved in the bioactivation of the antiplatelet prodrug clopidogrel and common CYP2C19 loss-of-function alleles are associated with adverse cardiovascular events. To assess the impact of the CYP2C19*17 increased activity allele in the Ashkenazi Jewish (AJ) and Sephardi Jewish (SJ) populations and to determine the frequencies of additional variant alleles, 250 AJ and 135 SJ individuals were genotyped for CYP2C19*2-*10, *12-*17, *22 and P-glycoprotein (ABCB1) c.3435C>T. Importantly, CYP2C19*4, a loss-of-function allele, was identified in linkage disequilibrium with *17. This novel haplotype, designated CYP2C19*4B, significantly alters the interpretation of CYP2C19 genotyping when testing *17. Moreover, genotyping CYP2C19*17 changed the frequency of extensive metabolizers from ∼70 to ∼40%, reclassifying ∼30% as ultrarapid metabolizers. Combining CYP2C19 and ABCB1 identified ∼1 in 3 AJ and ∼1 in 2 SJ individuals at increased risk for adverse responses to clopidogrel. These data underscore the importance of including *4B and *17 when clinically genotyping CYP2C19.
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Affiliation(s)
- S A Scott
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine, New York, NY 10029, USA.
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Wang H, An N, Wang H, Gao Y, Liu D, Bian T, Zhu J, Chen C. Evaluation of the effects of 20 nonsynonymous single nucleotide polymorphisms of CYP2C19 on S-mephenytoin 4'-hydroxylation and omeprazole 5'-hydroxylation. Drug Metab Dispos 2011; 39:830-7. [PMID: 21325430 DOI: 10.1124/dmd.110.037549] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
CYP2C19 is a highly polymorphic enzyme that affects the metabolism of a wide range of therapeutic drugs. Almost all the identified alleles of CYP2C19 are derived from nonsynonymous single nucleotide polymorphisms (nsSNPs). The objective of this study was to functionally characterize 20 nsSNPs of CYP2C19, distributed throughout the entire coding region, most of which have not been thoroughly characterized. cDNAs of these variants were constructed and expressed in yeast cells. All variants had similar levels of apoprotein and holoprotein expression, except for CYP2C19.16 and D360N, which had significantly lower holoprotein levels than the wild-type (WT) CYP2C19 enzyme, and CYP2C19.5B, which showed only apoprotein. The activity of the CYP2C19 variants was investigated using two substrates, S-mephenytoin and omeprazole, and six different kinetic parameters were measured. CYP2C19.5B, CYP2C19.6, and CYP2C19.8 were found to be catalytically inactive. The entire dataset of the remaining 17 variants, together with the WT, was analyzed by multivariate analysis. This analysis indicated that CYP2C19.9, CYP2C19.10, CYP2C19.16, CYP2C19.18, CYP2C19.19, A161P, W212C, and D360N were substantially altered in catalytic properties in comparison with the WT, with each of these variants exhibiting either dramatically decreased catalytic activities or higher K(m) values. These results not only generally confirmed the function of previously reported variants but also identified additional reduced-function variants. These findings will greatly extend our understanding of CYP2C19 genetic polymorphisms in humans as well as facilitate the structure-function study of the CYP2C19 protein.
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Affiliation(s)
- Huijuan Wang
- National Engineering Research Center for Miniaturized Detection Systems, School of Life Sciences, Northwest University, Xi'an, China
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Drögemöller BI, Wright GEB, Niehaus DJH, Koen L, Malan S, Da Silva DM, Hillermann-Rebello R, La Grange AM, Venter M, Warnich L. Characterization of the genetic profile of CYP2C19 in two South African populations. Pharmacogenomics 2010; 11:1095-103. [PMID: 20712527 DOI: 10.2217/pgs.10.90] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIMS This study was aimed at elucidating the common sequence variation present in the CYP2C19 gene within the South African Xhosa population and comparing it with the Cape Mixed Ancestry (CMA) population for possible future pharmacogenetic applications. MATERIALS & METHODS Common sequence variation was identified through the resequencing of 15 Xhosa individuals. The detected variants were prioritized for genotyping in an additional 85 Xhosa and 75 CMA individuals, while 5 -upstream variants were analyzed using dual luciferase reporter assays. RESULTS Resequencing of the Xhosa population revealed 30 variants, including the novel CYP2C19*27 and CYP2C19*28 alleles. CYP2C19*27, characterized by -1041G>A, caused a twofold decrease in luciferase activity, while CYP2C19*28 is characterized by the nonsynonymous V374I variant. In addition, the previously characterized variants, CYP2C19*2, CYP2C19*9 and CYP2C19*17, were present in both populations, while CYP2C19*3 was only observed in the CMA population. CONCLUSION Our data demonstrate that both the Xhosa and CMA populations exhibit unique genetic profiles that could influence the outcome of drug therapy in these populations.
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Seripa D, Pilotto A, Panza F, Matera MG, Pilotto A. Pharmacogenetics of cytochrome P450 (CYP) in the elderly. Ageing Res Rev 2010; 9:457-74. [PMID: 20601196 DOI: 10.1016/j.arr.2010.06.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 05/28/2010] [Accepted: 06/01/2010] [Indexed: 12/22/2022]
Abstract
The genetics of cytochrome P450 (CYP) is a very active area of multidisciplinary research, overlapping the interest of medicine, biology and pharmacology, being the CYP enzyme system responsible for the metabolism of more than 80% of the commercially available drugs. Variations in CYP encoding genes are responsible for inter-individual differences in CYP production or function, with severe clinical consequences as therapeutic failures (TFs) and adverse drug reactions (ADRs), being ADRs worldwide primary causes of morbidity and mortality in elderly people. In fact, the prevalence of both TFs and ADRs strongly increased in the presence of multiple pharmacological treatments, a common status in subjects aging 65 years and over. The present article explored some basic concepts of human genetics that have important implications in the genetics of CYP. An attempted to transfer these basic concepts to the genetic data reported by the Home Page of The Human Cytochrome P450 (CYP) Allele Nomenclature Committee was also made, focusing on the current knowledge of CYP genetics. The status of what we know and what we need to know is the base for the clinical applications of pharmacogenetics, in which personalized drug treatments constituted the main aim, in particular in patients attending a geriatric ward.
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Affiliation(s)
- Davide Seripa
- Geriatric Unit & Gerontology-Geriatrics Research Laboratory, Department of Medical Sciences, IRCCS Casa Sollievo della Sofferenza, Viale Cappuccini 1, 71013 San Giovanni Rotondo (FG), Italy.
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Yang JC, Lin CJ. CYP2C19 genotypes in the pharmacokinetics/pharmacodynamics of proton pump inhibitor-based therapy of Helicobacter pylori infection. Expert Opin Drug Metab Toxicol 2010; 6:29-41. [PMID: 19968574 DOI: 10.1517/17425250903386251] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
IMPORTANCE OF THE FIELD Proton pump inhibitors (PPIs) are potent gastric acid inhibitors. Therapies with a PPI and antibiotics are used to cure Helicobacter pylori (H. pylori) infection, which is closely related to many gastrointestinal diseases. Most PPIs are mainly metabolized by cytochrome 2C19 (CYP2C19). The genetic polymorphisms of CYP2C19 may lead to the differences in pharmacokinetics (PK), pharmacodynamics (PD) and clinical efficacy of PPIs. AREAS COVERED IN THIS REVIEW The roles of PPIs on the eradication of H. pylori are summarized. The impact f CYP2C19 polymorphism on the PK and PD of PPIs is addressed and related to the present status of therapy for H. pylori infection. The opinions on the strategy of PPIs-based therapies of H. pylori infection are provided. WHAT THE READER WILL GAIN Update the factors that may influence the PPIs-based therapies of H. pylori infection. TAKE HOME MESSAGE The eradication rates of H. pylori infection are significantly different between patients who are CYP2C19 extensive metabolizers and poor metabolizers, partly because of the differences in the PK and PD of PPIs. Nonetheless, the differences can be improved by adjusting the regimens of PPIs and using antibiotics that have less H. pylori-resistance.
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Affiliation(s)
- Jyh-Chin Yang
- National Taiwan University, Hospital and College of Medicine, Department of Internal Medicine, Taipei, Taiwan
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Janha RE, Sisay-Joof F, Hamid-Adiamoh M, Worwui A, Chapman HL, Opara H, Dunyo S, Milligan P, Rockett K, Winstanley P, Pirmohamed M, Miller AK, Conway DJ, Walton RT. Effects of genetic variation at the CYP2C19/CYP2C9 locus on pharmacokinetics of chlorcycloguanil in adult Gambians. Pharmacogenomics 2009; 10:1423-31. [PMID: 19761366 DOI: 10.2217/pgs.09.72] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIMS Antimalarial biguanides are metabolized by CYP2C19, thus genetic variation at the CYP2C locus might affect pharmacokinetics and so treatment outcome for malaria. MATERIALS & METHODS Polymorphisms in CYP2C19 and CYP2C9 in 43 adult Gambians treated with chlorproguanil/dapsone for uncomplicated malaria were assessed. Chlorcycloguanil pharmacokinetics were measured and associations with CYP2C19 and CYP2C9 alleles and CYP2C19 metabolizer groups investigated. RESULTS All CYP2C19/CYP2C9 alleles obeyed Hardy-Weinberg equilibrium. There were 15 CYP2C19/2C9 haplotypes with a common haplotype frequency of 0.23. Participants with the CYP2C19*17 allele had higher chlorcycloguanil area under the concentration versus curve at 24 h (AUC(0-24)) than those without (geometric means: 317 vs 216 ng.h/ml; ratio of geometric means: 1.46; 95% CI: 1.03 to 2.09; p = 0.0363) and higher C(max) (geometric mean ratio: 1.52; 95% CI: 1.13 to 2.05; p = 0.0071). CONCLUSION CYP2C19*17 determines antimalarial biguanide metabolic profile at the CYP2C19/CYP2C9 locus.
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Affiliation(s)
- Ramatoulie E Janha
- Medical Research Council Laboratories, Fajara, Banjul, The Gambia, West Africa.
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