CYP2C9*1B promoter polymorphisms, in linkage with CYP2C19*2, affect phenytoin autoinduction of clearance and maintenance dose. 2010

Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.

The commonly prescribed antiepileptic drug phenytoin has a narrow therapeutic range and wide interindividual variability in clearance explained in part by CYP2C9 and CYP2C19 coding variants. After finding a paradoxically low urinary phenytoin metabolite (S)/(R) ratio in subjects receiving phenytoin maintenance therapy with a CYP2C9*1/*1 and CYP2C19*1/*2 genotype, we hypothesized that CYP2C9 regulatory polymorphisms (rPMs), G-3089A and -2663delTG, in linkage disequilibrium with CYP2C19*2 were responsible. These rPMs explained as much as 10% of the variation in phenytoin maintenance dose in epileptic patients, but were not correlated with other patients' warfarin dose requirements or with phenytoin metabolite ratio in human liver microsomes. We hypothesized the rPMs affected CYP2C9 induction by phenytoin, a pregnane X receptor (PXR), and constitutive androstane receptor (CAR) activator. Transfection studies showed that CYP2C9 reporters with wild-type versus variant alleles had similar basal activity but significantly greater phenytoin induction by cotransfected PXR, CAR, and Nrf2 and less Yin Yang 1 transcription factor repression. Phenytoin induction of CYP2C9 was greater in human hepatocytes with the CYP2C9 wild type versus variant haplotype. Therefore, CYP2C9 rPMs affect phenytoin-dependent induction of CYP2C9 and phenytoin metabolism in humans, with an effect size comparable with that for CYP2C9*2 and 2C9*3. These findings may also be relevant to the clinical use of other PXR, CAR, and Nrf2 activators.

UI MeSH Term Description Entries
D008099 Liver A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances. Livers
D008862 Microsomes, Liver Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough. Liver Microsomes,Liver Microsome,Microsome, Liver
D008969 Molecular Sequence Data Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories. Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010672 Phenytoin An anticonvulsant that is used to treat a wide variety of seizures. It is also an anti-arrhythmic and a muscle relaxant. The mechanism of therapeutic action is not clear, although several cellular actions have been described including effects on ion channels, active transport, and general membrane stabilization. The mechanism of its muscle relaxant effect appears to involve a reduction in the sensitivity of muscle spindles to stretch. Phenytoin has been proposed for several other therapeutic uses, but its use has been limited by its many adverse effects and interactions with other drugs. Diphenylhydantoin,Fenitoin,Phenhydan,5,5-Diphenylhydantoin,5,5-diphenylimidazolidine-2,4-dione,Antisacer,Difenin,Dihydan,Dilantin,Epamin,Epanutin,Hydantol,Phenytoin Sodium,Sodium Diphenylhydantoinate,Diphenylhydantoinate, Sodium
D011401 Promoter Regions, Genetic DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes. rRNA Promoter,Early Promoters, Genetic,Late Promoters, Genetic,Middle Promoters, Genetic,Promoter Regions,Promoter, Genetic,Promotor Regions,Promotor, Genetic,Pseudopromoter, Genetic,Early Promoter, Genetic,Genetic Late Promoter,Genetic Middle Promoters,Genetic Promoter,Genetic Promoter Region,Genetic Promoter Regions,Genetic Promoters,Genetic Promotor,Genetic Promotors,Genetic Pseudopromoter,Genetic Pseudopromoters,Late Promoter, Genetic,Middle Promoter, Genetic,Promoter Region,Promoter Region, Genetic,Promoter, Genetic Early,Promoter, rRNA,Promoters, Genetic,Promoters, Genetic Middle,Promoters, rRNA,Promotor Region,Promotors, Genetic,Pseudopromoters, Genetic,Region, Genetic Promoter,Region, Promoter,Region, Promotor,Regions, Genetic Promoter,Regions, Promoter,Regions, Promotor,rRNA Promoters
D004305 Dose-Response Relationship, Drug The relationship between the dose of an administered drug and the response of the organism to the drug. Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D004790 Enzyme Induction An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis. Induction, Enzyme
D004827 Epilepsy A disorder characterized by recurrent episodes of paroxysmal brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge. Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy). (From Adams et al., Principles of Neurology, 6th ed, p313) Aura,Awakening Epilepsy,Seizure Disorder,Epilepsy, Cryptogenic,Auras,Cryptogenic Epilepsies,Cryptogenic Epilepsy,Epilepsies,Epilepsies, Cryptogenic,Epilepsy, Awakening,Seizure Disorders
D005838 Genotype The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS. Genogroup,Genogroups,Genotypes
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man

Related Publications

Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
December 2002, Clinical pharmacology and therapeutics,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
October 2004, Therapeutic drug monitoring,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
October 2004, Zhonghua yi xue za zhi,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
January 2001, The pharmacogenomics journal,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
June 2016, The pharmacogenomics journal,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
November 2005, Pharmacogenetics and genomics,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
July 2021, Pharmacogenomics,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
January 2017, Hippokratia,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
January 2017, Journal of thrombosis and thrombolysis,
Amarjit S Chaudhry, and Thomas J Urban, and Jatinder K Lamba, and Angela K Birnbaum, and Rory P Remmel, and Murali Subramanian, and Stephen Strom, and Joyce H You, and Dalia Kasperaviciute, and Claudia B Catarino, and Rodney A Radtke, and Sanjay M Sisodiya, and David B Goldstein, and Erin G Schuetz
May 2006, The Indian journal of medical research,
Copied contents to your clipboard!