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Tavares LC, Marcatto LR, Santos PCJL. Genotype-guided warfarin therapy: current status. Pharmacogenomics 2018; 19:667-685. [PMID: 29701078 DOI: 10.2217/pgs-2017-0207] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Warfarin pharmacogenomics has been an extensively studied field in the last decades as it is focused on personalized therapy to overcome the wide interpatient warfarin response variability and decrease the risk of side effects. In this expert review, besides briefly summarizing the current knowledge about warfarin pharmacogenetics, we also present an overview of recent studies that aimed to assess the efficacy, safety and economic issues related to genotype-based dosing algorithms used to guide warfarin therapy, including randomized and controlled clinical trials, meta-analyses and cost-effectiveness studies. To date, the findings still present disparities, mostly because of standard limitations. Thus, further studies should be encouraged to try to demonstrate the benefits of the application of warfarin pharmacogenomic dosing algorithms in clinical practice.
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Affiliation(s)
- Letícia C Tavares
- Laboratory of Genetics & Molecular Cardiology, Heart Institute (InCor), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, SP 05403-900, Brazil
| | - Leiliane R Marcatto
- Laboratory of Genetics & Molecular Cardiology, Heart Institute (InCor), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, SP 05403-900, Brazil
| | - Paulo C J L Santos
- Department of Pharmacology, Universidade Federal de Sao Paulo UNIFESP, SP 04044-020, Brazil
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Brennan FX, Gardner KR, Lombard J, Perlis RH, Fava M, Harris HW, Scott R. A Naturalistic Study of the Effectiveness of Pharmacogenetic Testing to Guide Treatment in Psychiatric Patients With Mood and Anxiety Disorders. Prim Care Companion CNS Disord 2015; 17:14m01717. [PMID: 26445691 PMCID: PMC4560190 DOI: 10.4088/pcc.14m01717] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 12/22/2014] [Indexed: 10/23/2022] Open
Abstract
OBJECTIVE To examine the effectiveness of genetic testing in a real-world setting and to assess its impact on clinician treatment decisions. METHOD This was a naturalistic, unblinded, prospective analysis of psychiatric patients and clinicians who utilized a commercially available genetic test (between April and October of 2013), which incorporates 10 genes related to pharmacokinetics and pharmacodynamics of psychiatric medications. Each patient's genetic results were provided to participating clinicians, who completed a baseline survey including patient medications, history, and severity of illness. Clinicians were prompted to complete surveys within 1 week of receiving the genetic results and again 3 months later. Patients likewise completed assessments of depression, anxiety, medication side effects, and quality of life at baseline, 1 month, and 3 months. RESULTS Data from 685 patients were collected. Approximately 70% and 29% of patients had primary diagnoses of either a mood or anxiety disorder, respectively. Clinician-reported data, as measured by the Clinical Global Impressions-Improvement scale, indicated that 87% of patients showed clinically measurable improvement (rated as very much improved, much improved, or minimally improved), with 62% demonstrating clinically significant improvement. When analysis was restricted to the 69% of individuals with ≥ 2 prior treatment failures, 91% showed clinically measurable improvement. Patients also reported significant decreases in depression (P < .001), anxiety (P < .001), and medication side effects (P < .001) and increases in quality of life (P < .001). CONCLUSIONS These results suggest that a substantial proportion of individuals receiving pharmacogenetic testing showed clinically significant improvements on multiple measures of symptoms, adverse effects, and quality of life over 3 months. In the absence of a treatment-as-usual comparator, the proportion of improvement attributable to the test cannot be estimated. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01507155.
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Affiliation(s)
- Francis X Brennan
- Genomind, Inc, King of Prussia, Pennsylvania (Drs Brennan, Lombard, and Scott and Ms Gardner); Department of Psychiatry, Massachusetts General Hospital, Boston (Drs Perlis and Fava); and North Carolina Elderly Psychiatric Services, Raleigh (Dr Harris)
| | - Kathryn R Gardner
- Genomind, Inc, King of Prussia, Pennsylvania (Drs Brennan, Lombard, and Scott and Ms Gardner); Department of Psychiatry, Massachusetts General Hospital, Boston (Drs Perlis and Fava); and North Carolina Elderly Psychiatric Services, Raleigh (Dr Harris)
| | - Jay Lombard
- Genomind, Inc, King of Prussia, Pennsylvania (Drs Brennan, Lombard, and Scott and Ms Gardner); Department of Psychiatry, Massachusetts General Hospital, Boston (Drs Perlis and Fava); and North Carolina Elderly Psychiatric Services, Raleigh (Dr Harris)
| | - Roy H Perlis
- Genomind, Inc, King of Prussia, Pennsylvania (Drs Brennan, Lombard, and Scott and Ms Gardner); Department of Psychiatry, Massachusetts General Hospital, Boston (Drs Perlis and Fava); and North Carolina Elderly Psychiatric Services, Raleigh (Dr Harris)
| | - Maurizio Fava
- Genomind, Inc, King of Prussia, Pennsylvania (Drs Brennan, Lombard, and Scott and Ms Gardner); Department of Psychiatry, Massachusetts General Hospital, Boston (Drs Perlis and Fava); and North Carolina Elderly Psychiatric Services, Raleigh (Dr Harris)
| | - Herbert W Harris
- Genomind, Inc, King of Prussia, Pennsylvania (Drs Brennan, Lombard, and Scott and Ms Gardner); Department of Psychiatry, Massachusetts General Hospital, Boston (Drs Perlis and Fava); and North Carolina Elderly Psychiatric Services, Raleigh (Dr Harris)
| | - Rachel Scott
- Genomind, Inc, King of Prussia, Pennsylvania (Drs Brennan, Lombard, and Scott and Ms Gardner); Department of Psychiatry, Massachusetts General Hospital, Boston (Drs Perlis and Fava); and North Carolina Elderly Psychiatric Services, Raleigh (Dr Harris)
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Linga VG, Patchva DB, Mallavarapu KM, Tulasi V, Kalpathi KI, Pillai A, Gundeti S, Rajappa SJ, Digumarti R. Thiopurine methyltransferase polymorphisms in children with acute lymphoblastic leukemia. Indian J Med Paediatr Oncol 2014; 35:276-80. [PMID: 25538405 PMCID: PMC4264274 DOI: 10.4103/0971-5851.144989] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Introduction: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. 6-mercaptopurine (6-MP) and methotrexate are backbone drugs for maintenance phase of treatment. Purine Analogs 6-MP/6-thioguanine/azathiopurine are metabolized to its inactive form by the enzyme thiopurine methyltransferase (TPMT). Ninety percent of the population harbor wild type on both alleles (TPMT wild/wild), 10% are heterozygous, that is, one allele is mutant (TPMT wild/mutant) and 0.3% are homozygous, that is, both allele are mutant (TPMT mutant/mutant). In heterozygous and homozygous variant, activity of enzyme is low, leading to a higher incidence of toxicity (myelosuppression). Aim: The primary objective was to access the polymorphism of the enzyme, TPMT, in Children with ALL. Secondary objective was to correlate TPMT genotype with 6-MP toxicities. Materials and Methods: Seventy-two children with newly diagnosed ALL during first maintenance phase were serially enrolled after obtaining consent. Five ml of peripheral blood was drawn and DNA extracted. TPMT 2 polymorphisms were performed using Allele specific polymerase chain reaction (PCR) and TPMT 3B and 3C are performed by PCR-restriction fragment length polymorphism. Results: Sixty-nine children of 72 (95.8%) were wild for TPMT polymorphism and 3 (4.2%) were heterozygous for TPMT. Among the heterozygous variant one each (33.3%) were heterozygous for 2A, 3A, 3C. Febrile neutropenia was the most common toxicity in both wild and heterozygous group. Conclusion: The frequency of TPMT polymorphisms in children with ALL is 4.2%. Heterozygous variant is this study are one each (33%) of 2A, 3A, 3C.
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Affiliation(s)
- Vijay Gandhi Linga
- Department of Medical Oncology, Nizams Institute of Medical Science, Hyderabad, Telangana, India
| | - Dorra Babu Patchva
- Department of Pharmacology, Apollo Institute of Medical Science and Reasearch, Hyderabad, Telangana, India
| | | | - Venkata Tulasi
- Department of Medical Oncology, Basavatarakam Indo American Cancer Institute and Research, Hyderabad, Telangana, India
| | | | - Ashok Pillai
- Department of Medical Oncology, Nizams Institute of Medical Science, Hyderabad, Telangana, India
| | - Sadashivudu Gundeti
- Department of Medical Oncology, Nizams Institute of Medical Science, Hyderabad, Telangana, India
| | - Senthil J Rajappa
- Department of Medical Oncology, Basavatarakam Indo American Cancer Institute and Research, Hyderabad, Telangana, India
| | - Raghunadharao Digumarti
- Director and Head, Department of Medical Oncology, Tata Memorial Hospital, Aganampudi, Vishakapatnam, Andra Pradesh, India
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The potential utility of pharmacogenetic testing in psychiatry. PSYCHIATRY JOURNAL 2014; 2014:730956. [PMID: 25587529 PMCID: PMC4281386 DOI: 10.1155/2014/730956] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 11/23/2014] [Indexed: 12/14/2022]
Abstract
Over the last decade, pharmacogenetics has become increasingly significant to clinical practice. Psychiatric patients, in particular, may benefit from pharmacogenetic testing as many of the psychotropic medications prescribed in practice lead to varied response rates and a wide range of side effects. The use of pharmacogenetic testing can help tailor psychotropic treatment and inform personalized treatment plans with the highest likelihood of success. Recently, many studies have been published demonstrating improved patient outcomes and decreased healthcare costs for psychiatric patients who utilize genetic testing. This review will describe evidence supporting the clinical utility of genetic testing in psychiatry, present several case studies to demonstrate use in everyday practice, and explore current patient and clinician opinions of genetic testing.
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Constable S, Johnson MR, Pirmohamed M. Pharmacogenetics in clinical practice: considerations for testing. Expert Rev Mol Diagn 2014; 6:193-205. [PMID: 16512779 DOI: 10.1586/14737159.6.2.193] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Pharmacogenetics is a rapidly evolving field that will undoubtedly lead to the development of pharmacogenetic tests. Such tests will need to be assimilated into healthcare systems, but represent a further call on scarce healthcare resources. Therefore, in order for a pharmacogenetic test to fulfill its potential beyond the laboratory and into the clinical environment, it must prove itself on a wide range of multifaceted criteria. The test must have proven and reproducible analytical and clinical validity, and stand up to critical appraisal of clinical utility and cost-effectiveness. Pharmacogenetic testing can be considered to be a form of screening, and the experience that has been gained to date in evaluating other forms of screening tests may prove beneficial in evaluating pharmacogenetic technology. It is essential that the goals of pharmacogenetic testing are defined as early as possible to ensure that appropriate studies can be designed to provide the evidence base, and thereby enable appropriate evaluation of the technology by clinicians and healthcare administrators for incorporation into clinical practice. This review focuses on issues that will need to be considered in the scientific assessment of pharmacogenetic testing.
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Affiliation(s)
- Simon Constable
- Department of Pharmacology & Therapeutics, Ashton Street Medical School, University of Liverpool, Ashton Street, Liverpool, L69 3GE, UK.
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Bartlett G, Antoun J, Zgheib NK. Theranostics in primary care: pharmacogenomics tests and beyond. Expert Rev Mol Diagn 2013; 12:841-55. [PMID: 23249202 DOI: 10.1586/erm.12.115] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Theranostics represents a broadening in the scope of personalized medicine to include companion diagnostics for health interventions ranging from drugs to vaccines, as well as individual susceptibility to disease. Surprisingly, in the course of this broadening of personalized medicine discourse, relatively little attention has been paid to primary care (as compared with tertiary healthcare settings) despite its vast patient population and being a crucial entry point to health services. Recent advances in pharmacogenomics (PGx), a classical theranostics application whereby genotyping and/or gene expression-based tests are used for targeted or optimal therapy, revealed new opportunities to characterize more precisely human genomic variation and the ways in which it contributes to person-to-person and population variations in drug response. In the immediate foreseeable future, the primary-care physicians are expected to play an ever increasing crucial role in PGx-based prescribing in order to reduce the rates of adverse drug events and improve drug efficacy, yet PGx testing in primary care remains limited. In this article, the authors review the advances in PGx applications, the barriers for their adoption in the clinic from a primary care point of view and the efforts that are being undertaken to move PGx forward in this hitherto neglected application context of theranostic medicine. Finally, the authors propose several salient recommendations, including a 5-year forecast, to accelerate the current convergence between PGx and primary care.
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Affiliation(s)
- Gillian Bartlett
- Department of Family Medicine, Faculty of Medicine, McGill University, Montreal, QC, Canada
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Dogan M, Karabulut HG, Tukun A, Demirkazik A, Utkan G, Yalcin B, Dincol D, Akbulut H, Icli F. Relationship between antimetabolite toxicity and pharmacogenetics in Turkish cancer patients. Asian Pac J Cancer Prev 2013; 13:1553-6. [PMID: 22799365 DOI: 10.7314/apjcp.2012.13.4.1553] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION Antimetabolites may cause severe toxicity and even toxic death in cancer patients. Our aim was to evaluate the relationship between antimetabolite toxicity and pharmacogenetics in patients with severe clinical toxicity or alanine transaminase (ALT) elevation after fluorouracil (5FU), capecitabine or methotrexate administration. PATIENTS AND METHODS Cancer patients with severe antimetabolite toxicity were evaluated for methylenetetrahydrofolate reductase (MTHFR) gene C667T, thymidilate synthase (TS) gene 5' UTR variable number of tandem repeats (VNTR), dihydroprymidine dehydrogenase (DPYD) gene IVS14+1G/A, Xeroderma pigmentosum (XPD) gene Lys751Gln and X-ray repair cross-complementing group 1 (XRCC1) gene Arg399Gln polymorphisms. RESULTS Eighteen patients were enrolled, with a male/female ratio of 0.8. They had osteosarcoma in methotrexate group (n=7), gastrointestinal malignancies in 5FU group (n=9) and breast cancer in the capecitabine group (n=2). Mucositis and dermatitis occurred in all groups, together with ALT elevation in the methotrexate group and 2 toxic deaths were encountered. DPYD, TS, MTHFR, XPD and XRCC1 gene polymorphism rare allele frequencies were observed to be higher than in the general population. CONCLUSION Pharmacogenetics might contribute to tailored therapy.
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Affiliation(s)
- Mutlu Dogan
- Dept of Medical Oncology, School of Medicine, Ankara University, Ankara, Turkey.
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Concordance of DMET plus genotyping results with those of orthogonal genotyping methods. Clin Pharmacol Ther 2012; 92:360-5. [PMID: 22871999 DOI: 10.1038/clpt.2012.95] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
There are several hurdles to the clinical implementation of pharmacogenetics. One approach is to employ pre-prescription genotyping, involving interrogation of multiple pharmacogenetic variants using a high-throughput platform. We compared the performance of the Drug Metabolizing Enzymes and Transporters (DMET) Plus array (1,931 variants in 225 genes) with that of orthogonal genotyping methods in 220 pediatric patients. A total of 1,692 variants had call rates >98% and were in Hardy-Weinberg equilibrium. Of these, 259 were genotyped by at least one independent method, and a total of 19,942 single-nucleotide polymorphism (SNP)-patient sample pairs were evaluated. The concordance rate was 99.9%, with only 28 genotype discordances observed. For the genes deemed most likely to be clinically relevant (TPMT, CYP2D6, CYP2C19, CYP2C9, VKORC1, DPYD, UGT1A1, and SLCO1B1), a total of 3,799 SNP-patient sample pairs were evaluable and had a concordance rate of 99.96%. We conclude that the DMET Plus array performs well with primary patient samples, with the results in good concordance with those of several lower-throughput genotyping methods.
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Wan Rosalina WR, Teh LK, Mohamad N, Nasir A, Yusoff R, Baba AA, Salleh MZ. Polymorphism of ITPA 94C>A and risk of adverse effects among patients with acute lymphoblastic leukaemia treated with 6-mercaptopurine. J Clin Pharm Ther 2012; 37:237-41. [PMID: 21545474 DOI: 10.1111/j.1365-2710.2011.01272.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
WHAT IS KNOWN AND OBJECTIVE Genetic polymorphisms of thiopurine S-methyltransferase (TPMT) and inosine triphosphate pyrophosphohydrolase (ITPA 94C>A) contribute to variable responses, including fatal adverse effects, among subjects treated with 6-mercaptopurine (6-MP). Our objectives were to investigate the distribution of specific TPMT and ITPA genotypes in healthy subjects and patients with acute lymphoblastic leukaemia (ALL) from the three main ethnic groups (Malays, Chinese and Indians) in Malaysia and the association of the polymorphisms with adverse effects of 6-MP. METHODS Patients with ALL and healthy controls were recruited and genotyped for genetic variants of TPMT and ITPA 94C>A. The relationship between genotypes and clinical outcomes was investigated. RESULTS AND DISCUSSION Acute lymphoblastic leukaemia patients with allele ITPA 94A were more likely to develop fever and liver toxicity with 6-MP. The prevalence of TPMT variants was low and this makes it unlikely that testing for them would be useful in our populations. Only patients heterozygous for TPMT*3C were detected. WHAT IS NEW AND CONCLUSION Our results suggest that ITPA 94C>A testing, but not TPMT testing, may help in minimizing the adverse effects of 6-MP in Malaysian patients. However, whether this is true in clinical practice requires a larger study and formal randomized controlled evaluation.
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Affiliation(s)
- W R Wan Rosalina
- Pharmacogenomics Center (PROMISE), Faculty of Pharmacy, Universiti Teknologi MARA, Selangor, Malaysia
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Crews KR, Cross SJ, McCormick JN, Baker DK, Molinelli AR, Mullins R, Relling MV, Hoffman JM. Development and implementation of a pharmacist-managed clinical pharmacogenetics service. Am J Health Syst Pharm 2011; 68:143-50. [PMID: 21200062 DOI: 10.2146/ajhp100113] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
PURPOSE The development and implementation of a pharmacist-managed clinical pharmacogenetics service are described. SUMMARY A pharmacist-managed clinical pharmacogenetics service was designed and implemented at an academic specialty hospital to provide clinical pharmacogenetic testing for gene products important to the pharmacodynamics of medications used in the hospital's patients. A series of accredited educational seminars were conducted for our pharmacists to establish competencies in providing pharmacogenetic consults for the genes to be tested by the clinical pharmacogenetics service. The service was modeled after and integrated with an already-established clinical pharmacokinetics service. A steering committee was formed to evaluate the use of available tests, new evidence for implementation of additional tests, and other service quality metrics. All clinical pharmacogenetic test results are first reported to one of the pharmacists, who reviews the result and provides a written consultation. The consultation includes an interpretation of the result and recommendations for any indicated changes to therapy. In 2009, 136 clinical pharmacogenetic tests were performed. The service has been met with positive clinician feedback. The successful implementation of this service highlights the leadership role that pharmacists can take in moving pharmacogenetics from research to patient care. CONCLUSION The development of and experience with a pharmacist-managed clinical pharmacogenetics service are described. The program's success has depended on collaboration between the clinical laboratory and pharmacists, and pharmacists' pharmacogenetic recommendations have been well accepted by prescribers.
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Affiliation(s)
- Kristine R Crews
- Pharmaceutical Department, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
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12
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Need AC, Goldstein DB. Whole genome association studies in complex diseases: where do we stand? DIALOGUES IN CLINICAL NEUROSCIENCE 2010. [PMID: 20373665 PMCID: PMC3181943 DOI: 10.31887/dcns.2010.12.1/aneed] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Hundreds of genome-wide association studies have been performed in recent years in order to try to identify common variants that associate with complex disease. These have met with varying success. Some of the strongest effects of common variants have been found in lateonset diseases and in drug response. The major histocompatibility complex has also shown very strong association with a variety of disorders. Although there have been some notable success stories in neuropsychiatric genetics, on the whole, common variation has explained little of the high heritability of these traits. In contrast, early studies of rare copy number variants have led rapidly to a number of genes and loci that strongly associate with neuropsychiatric disorders. It is likely that the use of whole-genome sequencing to extend the study of rare variation in neuropsychiatry will greatly advance our understanding of neuropsychiatric genetics.
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Affiliation(s)
- Anna C Need
- Institute for Genome Sciences and Policy, Center for Human Genome Variation, Duke University, Durham, North Carolina 27708, USA
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Man M, Farmen M, Dumaual C, Teng CH, Moser B, Irie S, Noh GJ, Njau R, Close S, Wise S, Hockett R. Genetic variation in metabolizing enzyme and transporter genes: comprehensive assessment in 3 major East Asian subpopulations with comparison to Caucasians and Africans. J Clin Pharmacol 2010; 50:929-40. [PMID: 20173083 DOI: 10.1177/0091270009355161] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The advent of high-throughput technologies has proven valuable in the assessment of genetic differences and their effects on drug activation, metabolism, disposition, and transport. However, most studies to date have focused on a small number of genes or few alleles, some of which are rare and therefore observed infrequently or lacked rigorous ethnic characterization, thus reducing the ability to extrapolate within and among populations. In this study, the authors comprehensively assessed the allele frequencies of 165 variants comprising 27 drug-metabolizing enzyme and transporter (DMET) genes from 2188 participants across 3 major ethnic populations: Caucasians, Africans, and East Asians. This sample size was sufficiently large to demonstrate genetic differences among these major ethnic groups while concomitantly confirming similarities among East Asian subpopulations (Korean, Han Chinese, and Japanese). A comprehensive presentation of allele and genotype frequencies is included in the online supplement, and 3 of the most widely studied cytochrome P450 (CYP) genes, CYP2D6, CYP2C19, and CYP2C9; 2 non-CYP enzymes, NAT1 and TMPT; and 2 transporter genes, SLCO1B1 and SLCO2B1, are presented herein according to ethnic classification.
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Affiliation(s)
- Michael Man
- Discovery and Development Statistics, Eli Lilly and Company, Lilly Corporate Center DC 2026, Indianapolis, IN 46285, USA.
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Kim YI. Role of the MTHFR polymorphisms in cancer risk modification and treatment. Future Oncol 2009; 5:523-42. [PMID: 19450180 DOI: 10.2217/fon.09.26] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The role of folate, a water-soluble B vitamin, and single nucleotide polymorphisms (SNPs) in the folate metabolic pathway in human health and disease has been rapidly expanding. Recently, functionally significant SNPs in 5,10-methylenetetrahydrofolate reductase (MTHFR), a critical enzyme for intracellular folate homeostasis and metabolism, have been identified and characterized. The MTHFR SNPs are ideal candidates for investigating the role of SNPs in cancer risk modification and treatment because of their well-defined and highly relevant biochemical effects on intracellular folate composition and one-carbon transfer reactions. Indeed, a large body of molecular epidemiologic evidence suggests that the MTHFR 677 variant T allele is associated with cancer risk in a site-specific manner. Furthermore, biologically plausible mechanisms based on the functional consequences of changes in intracellular folate cofactors resulting from the MTHFR 677T variant exist to readily explain cancer risk modification associated with this variant. In addition, a growing body of in vitro and clinical evidence suggests that the MTHFR SNPs may be an important pharmacogenetic determinant of response to and toxicity of 5-fluorouracil (5FU) and methotrexate (MTX)-based cancer and anti-inflammatory chemotherapy. Furthermore, studies suggest that MTHFR inhibition may be a potential target for increasing chemosensitvity of cancer cells to 5FU-based chemotherapy. Because the MTHFR SNPs are prevalent and MTX and 5FU are widely used for the treatment of common cancers and inflammatory conditions, the pharmacogenetic role of the MTHFR SNPs has significant clinical implications. MTHFR SNPs may play an important role in providing rational, effective and safe tailored treatment to patients with cancer and inflammatory disorders requiring 5FU and MTX-based therapy. As such, largescale human studies and in vitro mechanistic studies are warranted to clarify the pharmacogenetic role of the MTHFR SNPs.
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Affiliation(s)
- Young-In Kim
- Department of Medicine, Room 7258, Medical Sciences Building, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
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Abstract
DrugBank is a freely available web-enabled database that combines detailed drug data with comprehensive drug-target and drug-action information. It was specifically designed to facilitate in silico drug-target discovery, drug design, drug-metabolism prediction, drug-interaction prediction, and general pharmaceutical education. One of the most unique and useful components of the DrugBank database is the information it contains on drug metabolism, drug-metabolizing enzymes and drug-target polymorphisms. As pharmacogenomics is fundamentally concerned with the role of genes and genetic variation of how an individual responds to a drug, DrugBank is able to offer a convenient venue to explore pharmacogenomic questions in silico. This paper provides a brief overview on DrugBank and how it can facilitate pharmacogenomic research.
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Affiliation(s)
- David S Wishart
- Departments of Computing Science & Biological Sciences, University of Alberta, Edmonton ABT6G2E8, Canada.
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Shai RM, Reichardt JKV, Chen TC. Pharmacogenomics of brain cancer and personalized medicine in malignant gliomas. Future Oncol 2008; 4:525-34. [PMID: 18684063 DOI: 10.2217/14796694.4.4.525] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The pharmacogenetics of cancer treatment has been aimed at identifying genetic components of interindividual variability in patients' response to cancer chemotherapy and toxicity. This, in turn, will establish an individually based treatment, and also elucidate the molecular basis of the treatment regimen for further improvements. Brain cancer is an instructive example for the potential contributions of pharmacogenomics to improved treatment in the 21st century. Patients with oligodendrogliomas have benefited from phamacogenomics, as there is a clear relationship between response to chemotherapy and chromosomal profile. Drug efficacy, safety and response could be improved by using pharmacogenomics to identify genetic markers that differentiate responder from nonresponder patient groups, as well as identifying patients likely to develop adverse drug reactions. This review will focus on how pharmacogenomics by microarray studies may lead to much more accurate tumor classification, drug and biomarker discovery, and drug efficacy testing. We will discuss relevant scientific advances in pharmacogenetics for more personalized chemotherapy.
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Affiliation(s)
- Ruty Mehrian Shai
- USC Keck School of Medicine, Department of Biochemistry and Molecular Biology, Institute for Genetic Medicine, Los Angeles, CA 90089, USA.
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Deeken JF, Slack R, Marshall JL. Irinotecan and uridine diphosphate glucuronosyltransferase 1A1 pharmacogenetics. Cancer 2008; 113:1502-10. [DOI: 10.1002/cncr.23777] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Dai Z, Papp AC, Wang D, Hampel H, Sadee W. Genotyping panel for assessing response to cancer chemotherapy. BMC Med Genomics 2008; 1:24. [PMID: 18547414 PMCID: PMC2442111 DOI: 10.1186/1755-8794-1-24] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Accepted: 06/11/2008] [Indexed: 01/02/2023] Open
Abstract
Background Variants in numerous genes are thought to affect the success or failure of cancer chemotherapy. Interindividual variability can result from genes involved in drug metabolism and transport, drug targets (receptors, enzymes, etc), and proteins relevant to cell survival (e.g., cell cycle, DNA repair, and apoptosis). The purpose of the current study is to establish a flexible, cost-effective, high-throughput genotyping platform for candidate genes involved in chemoresistance and -sensitivity, and treatment outcomes. Methods We have adopted SNPlex for genotyping 432 single nucleotide polymorphisms (SNPs) in 160 candidate genes implicated in response to anticancer chemotherapy. Results The genotyping panels were applied to 39 patients with chronic lymphocytic leukemia undergoing flavopiridol chemotherapy, and 90 patients with colorectal cancer. 408 SNPs (94%) produced successful genotyping results. Additional genotyping methods were established for polymorphisms undetectable by SNPlex, including multiplexed SNaPshot for CYP2D6 SNPs, and PCR amplification with fluorescently labeled primers for the UGT1A1 promoter (TA)nTAA repeat polymorphism. Conclusion This genotyping panel is useful for supporting clinical anticancer drug trials to identify polymorphisms that contribute to interindividual variability in drug response. Availability of population genetic data across multiple studies has the potential to yield genetic biomarkers for optimizing anticancer therapy.
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Affiliation(s)
- Zunyan Dai
- Program in Pharmacogenomics, Department of Pharmacology, Comprehensive Cancer Center, College of Medicine and Public Health, The Ohio State University, 5072 Graves Hall, 333 West 10th Avenue, Columbus, OH 43210-1239, USA.
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Jarjanazi H, Kiefer J, Savas S, Briollais L, Tuzmen S, Pabalan N, Ibrahim-Zada I, Mousses S, Ozcelik H. Discovery of genetic profiles impacting response to chemotherapy: application to gemcitabine. Hum Mutat 2008; 29:461-7. [DOI: 10.1002/humu.20732] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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21
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Are Thymidylate synthase and Methylene tetrahydrofolate reductase genes linked with methotrexate response (efficacy, toxicity) in Indian (Asian) rheumatoid arthritis patients? Clin Rheumatol 2008; 27:787-9. [DOI: 10.1007/s10067-008-0852-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Accepted: 01/16/2008] [Indexed: 10/22/2022]
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22
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Beeton-Kempen N, Shoko A, Blackburn J. Personalizing protein-drug interactions. PURE APPL CHEM 2008. [DOI: 10.1351/pac200880081811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The development of new drugs today is a hugely expensive process, with estimated costs of up to $1 billion to take a drug through to market. However, despite this seemingly massive expenditure, statistics show that the great majority of prescription drugs on the market today are only effective for around 40 % of the patients to whom they are administered. Worse still, recently there have been a series of high-profile instances where potentially block-busting FDA-approved drugs have subsequently been withdrawn due to unanticipated side effects that were only revealed when the drug entered use in the general population. A variety of factors are at play in underpinning such statistics, but at the heart of the problem is the fact that, despite the extensive knowledge being generated in the postgenomic era about the genetic differences between individuals, Western medicine still today largely ignores such differences. The hope therefore is that by gaining a greater understanding of the individual nature of disease progression and of drug response, we might move toward a new era of personalized medicine in which the right drug is prescribed at the right dose to treat the precise disease afflicting the specific patient. As a step along this road, this review will discuss new approaches in the pharmacogenomics field to understanding in a quantitative manner the molecular consequence of polymorphic variation and mutation, both on encoded protein function and on protein-drug interactions.
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Affiliation(s)
- Natasha Beeton-Kempen
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, Cape Town, South Africa
| | - Aubrey Shoko
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, Cape Town, South Africa
| | - Jonathan Blackburn
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory 7925, Cape Town, South Africa
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Dumaual C, Miao X, Daly TM, Bruckner C, Njau R, Fu DJ, Close-Kirkwood S, Bauer N, Watanabe N, Hardenbol P, Hockett RD. Comprehensive assessment of metabolic enzyme and transporter genes using the Affymetrix Targeted Genotyping System. Pharmacogenomics 2007; 8:293-305. [PMID: 17324118 DOI: 10.2217/14622416.8.3.293] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The combined effects of multiple polymorphisms in several drug-metabolizing enzyme and transporter genes can contribute to considerable interindividual variation in drug disposition and response. Therefore, it has been of increasing interest to generate scalable, flexible and cost-effective technologies for large-scale genotyping of the drug-metabolizing enzyme and transporter genes. However, the number of drug-metabolizing enzyme and transporter gene variants exceeds the capacity of current technologies to comprehensively assess multiple polymorphisms in a single, multiplexed assay. The Targeted Genotyping System (Affymetrix, CA, USA) provides a solution to this challenge, by combining molecular inversion probe technology with universal microarrays to provide a method that is capable of analyzing thousands of variants in a single reaction, while remaining relatively insensitive to cross-reactivity between reaction components. This review will focus on the Targeted Genotyping System and how this technology was adapted to enable comprehensive analysis of drug-metabolizing enzyme and transporter gene polymorphisms.
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Affiliation(s)
- Carmen Dumaual
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285, USA
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24
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Daly TM, Dumaual CM, Miao X, Farmen MW, Njau RK, Fu DJ, Bauer NL, Close S, Watanabe N, Bruckner C, Hardenbol P, Hockett RD. Multiplex assay for comprehensive genotyping of genes involved in drug metabolism, excretion, and transport. Clin Chem 2007; 53:1222-30. [PMID: 17510302 DOI: 10.1373/clinchem.2007.086348] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Drug metabolism is a multistep process by which the body disposes of xenobiotic agents such as therapeutic drugs. Genetic variation in the enzymes involved in this process can lead to variability in a patient's response to medication. METHODS We used molecular-inversion probe technology to develop a multiplex genotyping assay that can simultaneously test for 1227 genetic variants in 169 genes involved in drug metabolism, excretion, and transport. Within this larger set of variants, we performed analytical validation of a clinically defined core set of 165 variants in 27 genes to assess accuracy, imprecision, and dynamic range. RESULTS In a test set of 91 samples, genotyping accuracy for the core set probes was 99.8% for called genotypes, with a 1.2% no-call (NC) rate. The majority of the core set probes (133 of 165) had < or = 1 genotyping failure in the test set; a subset of 12 probes was responsible for the majority of failures (mainly NC). Genotyping results were reproducible upon repeat testing with overall within- and between-run variation of 1.1% and 1.4%, respectively-again, primarily NCs in a subset of probes. The assay showed stable genotyping results over a 6-fold range of input DNA. CONCLUSIONS This assay generates a comprehensive assessment of a patient's metabolic genotype and is a tool that can provide a more thorough understanding of patient-to-patient variability in pharmacokinetic responses to drugs.
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Affiliation(s)
- Thomas M Daly
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USA
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25
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Eisinger F, Moatti JP. [Diffusion of genetic testing in oncology: what criteria for regulation?]. Med Sci (Paris) 2007; 23:327-32. [PMID: 17349298 DOI: 10.1051/medsci/2007233327] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Does gene testing indicate a switch from an histopathological to a molecular approach of human diseases ? Disease management in oncology is already improved by gene testing, at least for some specific cancers. It is however necessary to distinguish the analysis of genes specific to the tumour which gives clues about the fate of the tumours, from those unique to the patients, which gives clues about the future of the person. For the latter so-called germline mutations, wide scale gene-default screening would put pressure on resource allocation from the health care systems of developed countries. Currently the cost of detecting of 700 genes in the whole French population would exceed the whole health budget of the country for the next 10 years. Even if we can anticipate a dramatic decrease in the unit cost of these genetic tests in the future, their diffusion should not be controlled exclusively by technological and market forces. In this paper, we propose to discuss four main parameters for regulating these genetic tests, using as an archetypal example their application to cancer prevention and treatment: (1) which specific cancer disease is targeted by the test (prevalence, incidence, likelihood of cure with current therapeutics, number of years of life potentially saved...); (2) what are the characteristics of the genes tested and which level of evidence is required about the predictive value of the test; (3) what are the size and characteristics of the population who will be offered the test, and (4) which process and public control are necessary before market approval of the test and reimbursement of related expenditures by health care insurance schemes.
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Affiliation(s)
- François Eisinger
- Institut Paoli-Calmettes, 232, Boulevard Sainte-Marguerite, 13009 Marseille, France.
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Abstract
Pharmacoeconomics and pharmacogenetics are two fields converging together as it is increasingly recognized that genetic markers predicting efficacy and toxicity to drugs can cost-effectively improve patient care. While pharmacogenetics aims at identifying genetic markers underlying the response to drugs, pharmacoeconomics aims at delivering healthcare cost-effectively. Several studies have investigated the potential cost-effectiveness of pharmacogenetic-based approaches. Recent evidences include screening for thiopurine methyltransferase gene polymorphisms to prevent azathioprine-induced myelosuppression, or screening for human leukocyte antigen (HLA)B5701 to prevent hypersensitivity reactions to abacavir therapy. Furthermore, examples suggesting a cost-effectiveness of markers predicting drug efficacy include screening the angiotensin-converting enzyme gene polymorphisms for statins therapy, the alpha-adducin gene variant for diuretic therapy and the assessment of human epidermal growth factor receptor (HER2) expression for trastuzumab therapy. However, thus far, all these pharmacoeconomic analyses are exploratory and validations in prospective randomized clinical trials are warranted.
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Affiliation(s)
- Thierry Dervieux
- Proprius Pharmaceuticals, 12264 El Camino Real, Suite 300, San Diego, CA 92130-3062, USA.
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Imyanitov EN, Moiseyenko VM. Molecular-based choice of cancer therapy: realities and expectations. Clin Chim Acta 2007; 379:1-13. [PMID: 17306783 DOI: 10.1016/j.cca.2007.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 01/03/2007] [Accepted: 01/06/2007] [Indexed: 01/29/2023]
Abstract
Current choice of cancer therapy is usually empirical and relies mainly on the statistical prediction of the treatment success. Molecular research provides some opportunities to personalize antitumor treatment. For example, life-threatening toxic reactions can be avoided by the identification of subjects, who carry susceptible genotypes of drug-metabolizing genes (e.g. TPMT, UGT1A1, MTHFR, DPYD). Tumor sensitivity can be predicted by molecular portraying of targets and other molecules associated with drug response. Tailoring of antiestrogen and trastuzumab therapy based on hormone and HER2 receptor status has already become a classical example of customized medicine. Other predictive markers have been identified both for cytotoxic and for targeted therapies, and include, for example, expression of TS, TP, DPD, OPRT, ERCC1, MGMT, TOP2A, class III beta-tubulin molecules as well as genomic alterations of EGFR, KIT, ABL oncogenes.
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Affiliation(s)
- Evgeny N Imyanitov
- Laboratory of Molecular Oncology, N.N. Petrov Institute of Oncology, St.-Petersburg, Russia.
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Dervieux T, Greenstein N, Kremer J. Pharmacogenomic and metabolic biomarkers in the folate pathway and their association with methotrexate effects during dosage escalation in rheumatoid arthritis. ACTA ACUST UNITED AC 2006; 54:3095-103. [PMID: 17009228 DOI: 10.1002/art.22129] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To evaluate the contribution of metabolites (methotrexate [MTX] and folate polyglutamate [PG] levels) and pharmacogenetic biomarkers in the folate pathway to the effects of MTX in patients with rheumatoid arthritis not previously treated with this antifolate. METHODS Forty-eight MTX-naive adult patients were enrolled in a prospective longitudinal study. MTX therapy was initiated at 7.5 mg/week and was increased every 4-6 weeks until a therapeutic response was achieved. Response was assessed using the Disease Activity Score in 28 joints (DAS28). Red blood cell (RBC) MTX and folate PG levels were measured with 9 common polymorphisms in the folate pathway. Statistical analyses consisted of generalized linear models and multivariate regressions. RESULTS After 6 months of therapy, the median weekly MTX dosage was 17.5 mg and the median decrease in the DAS28 was 2.0. There was a large interpatient variability in RBC MTXPG levels (median 35 nmoles/liter [interquartile range 28-51] at month 6). Patients with a lesser decrease in the DAS28 (fewer improvements) had lower RBC MTXPG levels (P < 0.05) despite the higher MTX dose administered (P < 0.05). RBC folate PG levels decreased significantly during treatment, and a lesser decrease in RBC folate PGs was associated with a lesser decrease in the DAS28 (P < 0.05). Primary side effects were gastrointestinal and neurologic in nature. Risk genotypes associated with toxicity were in gamma-glutamyl hydrolase (-401CC), 5-aminoimidazole-4-carboxamide ribonucleotide transformylase (347GG), methylenetetrahydrofolate reductase (1298AC/CC), methionine synthase (2756AA), and methionine synthase reductase (66GG). CONCLUSION RBC MTXPG levels are a useful means by which to monitor therapy. The genetic associations presented generate hypotheses, and confirmation in independent cohorts is warranted.
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Nagai H, Teramachi H, Tuchiya T. Recent advances in the development of anti-allergic drugs. Allergol Int 2006; 55:35-42. [PMID: 17075284 DOI: 10.2332/allergolint.55.35] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2005] [Indexed: 01/25/2023] Open
Abstract
Research over the past decade has provided information concerning the onset and treatment of allergic diseases, including bronchial asthma, allergic rhinitis and atopic dermatitis. Recent studies also indicated that allergic inflammation is the basic pathophysiology of allergic diseases and is closely associated with their progression and exacerbation. Our understanding of the mechanism of allergic inflammation with regard to therapeutic agents has improved as a result of immunological and molecular biological studies. While much effort has been paid to developing a new anti-allergic drug, allergic disease has yet to be completely conquered. More extensive research will allow the development of new therapeutics to combat allergic diseases. This article provides an overview of recent advances in the development of anti-allergic drugs.
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Affiliation(s)
- Hiroichi Nagai
- Department of Clinical Pharmacology, Gifu Pharmaceutical University, Gifu, Japan.
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Abstract
Few genetic markers are used routinely to predict clinical effectiveness and toxic effects despite the fact that physicians and their patients are consistently confronted with this balance. Because one of the goals of pharmacogenomics is to identify individuals and target populations that might have adverse outcomes, pharmaceutical companies have been reluctant to use a strategy that might identify patients who are not eligible for a particular treatment. This view is changing because drug-discovery programmes and treatments that target specific pathways, are showing improvements in surrogate and survival endpoints. HIV and cancer are now regarded as chronic diseases, which commonly need life-long systemic treatment from the time of diagnosis. HIV and cancer medicine have used pharmacogenomics to some extent in clinical care. Common and classic features of pharmacogenomics that are related to both antiretroviral treatment and to cytotoxic treatment are discussed in this review, providing a framework for individual treatment of these diseases.
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Affiliation(s)
- Justin Stebbing
- Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, UK
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Mathijssen RHJ, van Schaik RHN. Genotyping and phenotyping cytochrome P450: Perspectives for cancer treatment. Eur J Cancer 2006; 42:141-8. [PMID: 16325399 DOI: 10.1016/j.ejca.2005.08.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2005] [Accepted: 08/02/2005] [Indexed: 10/25/2022]
Abstract
As most anticancer agents display a narrow therapeutic window, patients may be susceptible to (extreme) toxicities or a lowered therapeutic outcome if not dosed adequately. Therefore, it is important to study factors which affect the pharmacokinetics and pharmacodynamics of these drugs. Among these, the contribution of genetic variation in drug metabolizing enzymes on the metabolism of anticancer agents has gathered interest, as it may potentially explain a substantial amount of interpatient variability in pharmacokinetics and drug response. Cytochrome P450, an oxidative enzyme-system involved in the breakdown of many drugs, is currently studied for correlations between genetic polymorphisms and anticancer drug metabolism. Also, alternative ways to predict the expression of cytochrome P450 have been developed (phenotyping measures) which may have additional value in creating a lowered interpatient variability, to minimize side-effects and maximize therapeutic efficacy.
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Affiliation(s)
- Ron H J Mathijssen
- Department of Medical Oncology and Clinical Chemistry, Erasmus University Medical Center, Rotterdam, The Netherlands.
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Pollera CF, Nelli F. Developing innovative strategies for advanced transitional cell carcinoma of the bladder. Expert Rev Anticancer Ther 2005; 6:83-92. [PMID: 16375647 DOI: 10.1586/14737140.6.1.83] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Several improvements in the treatment of advanced transitional cell malignancies have been provided by clinical trials in the past 10 years. Nonetheless, there are conflicting results regarding the effect of perioperative chemotherapy of muscle-invasive disease and new cytotoxic agents in the metastatic setting. The authors will discuss the results of major clinical trials and examine developing targeted-oriented treatment strategies.
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Affiliation(s)
- Camillo F Pollera
- Department of Medical Oncology, Presidio Ospedaliero Centrale di Belcolle, ASL di Viterbo, Strada Sammartinese snc, 01100, Viterbo, Italy.
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Csako G. Present and future of rapid and/or high-throughput methods for nucleic acid testing. Clin Chim Acta 2005; 363:6-31. [PMID: 16102738 DOI: 10.1016/j.cccn.2005.07.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Revised: 07/03/2005] [Accepted: 07/03/2005] [Indexed: 12/21/2022]
Abstract
BACKGROUND Behind the success of 'completing' the human genome project was a more than 30-year history of technical innovations for nucleic acid testing. METHODS Discovery of specific restriction endonucleases and reverse transcriptase was followed shortly by the development of the first diagnostic nucleic acid tests in the early 1970s. Introduction of Southern, Northern and dot blotting and DNA sequencing later in the 1970s considerably advanced the diagnostic capabilities. Nevertheless, it was the discovery of the polymerase chain reaction (PCR) in 1985 that led to an exponential growth in molecular biology and the introduction of practicable nucleic acid tests in the routine laboratory. The past two decades witnessed a continuing explosion of technological innovations in molecular diagnostics. In addition to classic PCR and reverse transcriptase PCR, numerous variations of PCR and alternative amplification techniques along with an ever-increasing variety of detection chemistries, closed tube (homogeneous) assays, and automated systems were developed. Discovery of real-time quantitative PCR and the development of oligonucleotide microarrays, the 'DNA chip', in the 1990s heralded the beginning of another revolution in molecular biology and diagnostics that is still in progress.
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Affiliation(s)
- Gyorgy Csako
- Department of Laboratory Medicine, W.G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892-1508, USA.
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