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Organista-Nava J, Gómez-Gómez Y, Saavedra-Herrera MV, Rivera-Ramírez AB, Terán-Porcayo MA, Alarcón-Romero LDC, Illades-Aguiar B, Leyva-Vázquez MA. Polymorphisms of the gamma-glutamyl hydrolase gene and risk of relapse to acute lymphoblastic leukemia in Mexico. Leuk Res 2010; 34:728-32. [PMID: 20197200 DOI: 10.1016/j.leukres.2009.11.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 11/29/2009] [Accepted: 11/29/2009] [Indexed: 11/28/2022]
Abstract
This study evaluated the association of -401C/T and +452C/T polymorphisms of gamma-glutamyl hydrolase and the risk of relapse to acute lymphoblastic leukemia. Genotyping was performed in 70 children with acute lymphoblastic leukemia and 140 healthy children. An association between the -401C/T polymorphism and the risk of relapse was found (p=0.028), patients with the -401T/T genotype have 10.83 (95% CI 1.30-90.14) more chance of a relapse of leukemia. No association was found between the +452C/T polymorphism and the risk of relapse. Therefore, our investigation suggests that the -401C/T polymorphism in the gamma-glutamyl hydrolase may be a factor involved in the generation of relapse to disease in patients with ALL.
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Affiliation(s)
- Jorge Organista-Nava
- Laboratorio de Biomedicina Molecular, Unidad Académica de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Ciudad Universitaria, Chilpancingo, Guerrero, Mexico
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52
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Leclerc GJ, Mou C, Leclerc GM, Mian AM, Barredo JC. Histone deacetylase inhibitors induce FPGS mRNA expression and intracellular accumulation of long-chain methotrexate polyglutamates in childhood acute lymphoblastic leukemia: implications for combination therapy. Leukemia 2010; 24:552-62. [DOI: 10.1038/leu.2009.282] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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53
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Jeha S, Pui CH. Risk-adapted treatment of pediatric acute lymphoblastic leukemia. Hematol Oncol Clin North Am 2010; 23:973-90, v. [PMID: 19825448 DOI: 10.1016/j.hoc.2009.07.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Optimal use of antileukemic agents and stringent application of risk-directed therapy in clinical trials have resulted in steady improvement in the outcome of children with acute lymphoblastic leukemia, with current cure rates exceeding 80% in developed countries. The intensity of treatment varies substantially among subsets of patients, as therapy is designed to reduce acute and long-term toxicity in low-risk groups while improving outcomes in poor risk groups by treatment intensification. Recent advances in genome-wide screening techniques, pharmacogenomic studies, and development of molecular therapeutics are ushering in an era of more refined personalized therapy.
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Affiliation(s)
- Sima Jeha
- Department of Oncology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA.
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Looking Toward the Future: Novel Strategies Based on Molecular Pathogenesis of Acute Lymphoblastic Leukemia. Hematol Oncol Clin North Am 2009; 23:1099-119, vii. [DOI: 10.1016/j.hoc.2009.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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55
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Paulsson K, Johansson B. High hyperdiploid childhood acute lymphoblastic leukemia. Genes Chromosomes Cancer 2009; 48:637-60. [PMID: 19415723 DOI: 10.1002/gcc.20671] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
High hyperdiploidy (51-67 chromosomes) is the most common cytogenetic abnormality pattern in childhood B-cell precursor acute lymphoblastic leukemia (ALL), occurring in 25-30% of such cases. High hyperdiploid ALL is characterized cytogenetically by a nonrandom gain of chromosomes X, 4, 6, 10, 14, 17, 18, and 21 and clinically by a favorable prognosis. Despite the high frequency of this karyotypic subgroup, many questions remain regarding the epidemiology, etiology, presence of other genetic changes, the time and cell of origin, and the formation and pathogenetic consequences of high hyperdiploidy. However, during the last few years, several studies have addressed some of these important issues, and these, as well as previous reports on high hyperdiploid childhood ALL, are reviewed herein.
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Affiliation(s)
- Kajsa Paulsson
- Department of Clinical Genetics, Lund University Hospital, Lund, Sweden.
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56
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Treviño LR, Yang W, French D, Hunger S, Carroll WL, Devidas M, Willman C, Neale G, Downing J, Raimondi S, Pui CH, Evans WE, Relling MV. Germline genomic variants associated with childhood acute lymphoblastic leukemia. Nat Genet 2009; 41:1001-5. [PMID: 19684603 PMCID: PMC2762391 DOI: 10.1038/ng.432] [Citation(s) in RCA: 373] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Accepted: 06/24/2009] [Indexed: 01/02/2023]
Abstract
Using the Affymetrix 500K Mapping array and publicly available genotypes, we identified 18 SNPs whose allele frequency differed significantly(P < 1 x 10(-5)) between pediatric acute lymphoblastic leukemia (ALL) cases (n = 317) and non-ALL controls (n = 17,958). Two SNPs in ARID5B not only differed between ALL and non-ALL groups (rs10821936, P = 1.4 x 10(-15), odds ratio (OR) = 1.91; rs10994982, P = 5.7 x 10(-9), OR = 1.62) but also distinguished B-hyperdiploid ALL from other subtypes (rs10821936, P = 1.62 x 10(-5), OR = 2.17; rs10994982, P = 0.003, OR 1.72). These ARID5B SNPs also distinguished B-hyperdiploid ALL from other subtypes in an independent validation cohort (n = 124 children with ALL; P = 0.003 and P = 0.0008, OR 2.45 and 2.86, respectively) and were associated with methotrexate accumulation and gene expression pattern in leukemic lymphoblasts. We conclude that germline variants affect susceptibility to, and characteristics of, specific ALL subtypes.
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MESH Headings
- Alleles
- Antimetabolites, Antineoplastic/metabolism
- Antimetabolites, Antineoplastic/therapeutic use
- Case-Control Studies
- Child
- Child, Preschool
- Chromosomes, Human, Pair 10
- Chromosomes, Human, Pair 7
- Cohort Studies
- DNA-Binding Proteins/genetics
- Dopa Decarboxylase/genetics
- Gene Dosage
- Gene Expression Regulation, Neoplastic/drug effects
- Gene Frequency
- Genetic Predisposition to Disease
- Genetic Variation
- Genome-Wide Association Study
- Germ Cells
- Germ-Line Mutation
- Haplotypes
- Humans
- Ikaros Transcription Factor/genetics
- Linkage Disequilibrium
- Methotrexate/metabolism
- Methotrexate/therapeutic use
- Odds Ratio
- Oncogene Proteins, Fusion/genetics
- Polyglutamic Acid/metabolism
- Polymorphism, Single Nucleotide
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/classification
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics
- Probability
- Reproducibility of Results
- Risk Factors
- Trans-Activators
- Transcription Factors/genetics
- White People/genetics
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Affiliation(s)
| | - Wenjian Yang
- St. Jude Children’s Research Hospital, Memphis TN, USA
| | | | | | | | | | | | | | - James Downing
- St. Jude Children’s Research Hospital, Memphis TN, USA
| | | | - Ching-Hon Pui
- St. Jude Children’s Research Hospital, Memphis TN, USA
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57
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58
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Duan S, Huang RS, Zhang W, Mi S, Bleibel WK, Kistner EO, Cox NJ, Dolan ME. Expression and alternative splicing of folate pathway genes in HapMap lymphoblastoid cell lines. Pharmacogenomics 2009; 10:549-63. [PMID: 19374514 DOI: 10.2217/pgs.09.8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM Folate is vital for cell growth and development through its important role in one-carbon metabolism - an essential process in the synthesis of amino acids and nucleic acids. Folate pathway genes have been considered as therapeutic targets of drugs for the treatment of cancer and other diseases. Racial and ethnic disparities of folate metabolism and outcome of antifolate therapies have been reported. In this study, we evaluate the genetic regulation for expression and alternative splicing of folate related genes in HapMap lymphoblastoid cell lines (LCLs) of individuals of European and African descent. MATERIALS & METHODS Gene and exon level expression and alternative splicing of folate pathway genes were compared in LCLs derived from the Centre d'Etude du Polymorphisme Humain (CEPH) from Utah (CEU) and the Yoruba from Ibadan (YRI) using a permutation-based test. A genome-wide association study was performed to search for SNPs associated with folate pathway gene expressions and alternative splicing in the combined population samples. RESULTS A total of 52 folate pathway genes were evaluated in the analysis of which 46 were expressed in the LCLs. There were 12 genes (26%) with differential gene-level expression and 23 genes (50%) with differential alternative splicing for exons or UTRs between the CEU and the YRI (permutation p <or= 0.05). The expression level of FPGS and the splicing indices of eight genes (ATP13A2, ASCC3L1, IFIH1, SMARCA5, SMARCA2, SETX, DDX52 and RUVBL2) were found to be associated with SNP genotypes in the combined populations (p < 3.2 x 10(-8), Bonferroni corrected p < 0.05). CONCLUSION Our study suggests that LCLs are an in vitro system suitable to evaluate the expression levels of folate pathway genes. The differential transcript-level expressions and the differentially alternative splicing events of exons or UTRs and associated SNP markers in 2 populations will enhance our understanding of the folate pathway and, thus, facilitate research in the areas of nutrition and folate metabolism.
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Affiliation(s)
- Shiwei Duan
- The University of Chicago, Chicago, IL 60637, USA
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59
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Ongaro A, De Mattei M, Della Porta MG, Rigolin G, Ambrosio C, Di Raimondo F, Pellati A, Masieri FF, Caruso A, Catozzi L, Gemmati D. Gene polymorphisms in folate metabolizing enzymes in adult acute lymphoblastic leukemia: effects on methotrexate-related toxicity and survival. Haematologica 2009; 94:1391-8. [PMID: 19648163 DOI: 10.3324/haematol.2009.008326] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND The antifolate agent methotrexate is an important component of maintenance therapy in acute lymphoblastic leukemia, although methotrexate-related toxicity is often a reason for interruption of chemotherapy. Prediction of toxicity is difficult because of inter-individual variability susceptibility to antileukemic agents. Methotrexate interferes with folate metabolism leading to depletion of reduced folates. DESIGN AND METHODS The aim of this study was to investigate the influence of polymorphisms for folate metabolizing enzymes with respect to toxicity and survival in adult patients with acute lymphoblastic leukemia treated with methotrexate maintenance therapy. To this purpose, we evaluated possible associations between genotype and hematologic and non-hematologic toxicity and effects on survival at 2 years of follow-up in patients with acute lymphoblastic leukemia. RESULTS Polymorphisms in the genes encoding for methylenetetrahydrofolate reductase (MTHFR 677C>T) and in dihydrofolate reductase (DHFR 19 bp deletion) significantly increased the risk of hepatotoxicity in single (odds ratio 5.23, 95% confidence interval 1.13-21.95 and odds ratio 4.57, 95% confidence interval 1.01-20.77, respectively) and in combined analysis (odds ratio 6.82, 95% confidence interval 1.38-33.59). MTHFR 677C>T also increased the risk of leukopenia and gastrointestinal toxicity, whilst thymidylate synthase 28 bp repeat polymorphism increased the risk of anemia (odds ratio 8.48, 95% confidence interval 2.00-36.09). Finally, patients with MTHFR 677TT had a decreased overall survival rate (hazard ratio 2.37, 95% confidence interval 1.46-8.45). CONCLUSIONS Genotyping of folate polymorphisms might be useful in adult acute lymphoblastic leukemia to optimize methotrexate therapy, reducing the associated toxicity with possible effects on survival.
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Affiliation(s)
- Alessia Ongaro
- Department of Morphology and Embryology, Section of Histology, University of Ferrara, Via Fossato di Mortara 64/B, 44100 Ferrara, Italy.
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60
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5,10-Methylenetetrahydrofolate reductase (MTHFR) low activity genotypes reduce the risk of relapse-related acute lymphoblastic leukemia (ALL). Leuk Res 2009; 33:1344-8. [PMID: 19178944 DOI: 10.1016/j.leukres.2008.12.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 12/04/2008] [Accepted: 12/17/2008] [Indexed: 11/21/2022]
Abstract
The reported correlation of defects in 5,10-methylenetetrahydrofolate reductase (MTHFR), the key enzyme of folate metabolism, with modulated risk for acute lymphoblastic leukemia (ALL) is ambiguous. We have elucidated the influence of MTHFR genotype on ALL development and relapse in 140 Slovenian pediatric ALL patients and 183 healthy controls. A decreased proportion of low activity MTHFR genotypes was found in a group of ALL patients with relapses compared to healthy controls (p = 0.022) and ALL cases without relapse (p = 0.027). Mutations in the MTHFR gene decrease the onset risk of ALL with relapse in the setting of no folate supplementation in pregnancy, but not of relapse-free ALL.
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61
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Pui CH, Relling MV, Evans WE. Is mega dose of methotrexate beneficial to patients with acute lymphoblastic leukemia? Leuk Lymphoma 2009; 47:2431-2. [PMID: 17169783 DOI: 10.1080/10428190600955837] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Ching-Hon Pui
- Departments of Oncology and Pharmaceutical Sciences, St Jude Children's Research Hospital, and Colleges of Medicine and Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38105, USA.
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62
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Pui CH, Campana D, Pei D, Bowman WP, Sandlund JT, Kaste SC, Ribeiro RC, Rubnitz JE, Raimondi SC, Onciu M, Coustan-Smith E, Kun LE, Jeha S, Cheng C, Howard SC, Simmons V, Bayles A, Metzger ML, Boyett JM, Leung W, Handgretinger R, Downing JR, Evans WE, Relling MV. Treating childhood acute lymphoblastic leukemia without cranial irradiation. N Engl J Med 2009; 360:2730-41. [PMID: 19553647 PMCID: PMC2754320 DOI: 10.1056/nejmoa0900386] [Citation(s) in RCA: 873] [Impact Index Per Article: 58.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Prophylactic cranial irradiation has been a standard treatment in children with acute lymphoblastic leukemia (ALL) who are at high risk for central nervous system (CNS) relapse. METHODS We conducted a clinical trial to test whether prophylactic cranial irradiation could be omitted from treatment in all children with newly diagnosed ALL. A total of 498 patients who could be evaluated were enrolled. Treatment intensity was based on presenting features and the level of minimal residual disease after remission-induction treatment. The duration of continuous complete remission in the 71 patients who previously would have received prophylactic cranial irradiation was compared with that of 56 historical controls who received it. RESULTS The 5-year event-free and overall survival probabilities for all 498 patients were 85.6% (95% confidence interval [CI], 79.9 to 91.3) and 93.5% (95% CI, 89.8 to 97.2), respectively. The 5-year cumulative risk of isolated CNS relapse was 2.7% (95% CI, 1.1 to 4.3), and that of any CNS relapse (including isolated relapse and combined relapse) was 3.9% (95% CI, 1.9 to 5.9). The 71 patients had significantly longer continuous complete remission than the 56 historical controls (P=0.04). All 11 patients with isolated CNS relapse remained in second remission for 0.4 to 5.5 years. CNS leukemia (CNS-3 status) or a traumatic lumbar puncture with blast cells at diagnosis and a high level of minimal residual disease (> or = 1%) after 6 weeks of remission induction were significantly associated with poorer event-free survival. Risk factors for CNS relapse included the genetic abnormality t(1;19)(TCF3-PBX1), any CNS involvement at diagnosis, and T-cell immunophenotype. Common adverse effects included allergic reactions to asparaginase, osteonecrosis, thrombosis, and disseminated fungal infection. CONCLUSIONS With effective risk-adjusted chemotherapy, prophylactic cranial irradiation can be safely omitted from the treatment of childhood ALL. (ClinicalTrials.gov number, NCT00137111.)
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Affiliation(s)
- Ching-Hon Pui
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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63
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Abstract
As the cure rates for haematological malignancies have improved, the exploration of the balance between efficacy and side effects has become a major research target. The antifolate methotrexate is widely used in the treatment of acute lymphoblastic leukaemia, non-Hodgkin lymphoma, and osteosarcoma. Even when given identical methotrexate doses, patients vary significantly in their response and pattern of toxicities. This diversity can, to some extent, be linked to sequence variations in genes involved in drug absorption, metabolism, excretion, cellular transport, and effector targets or target pathways. In the coming years pharmacogenomics is expected to change our approaches to individualised therapy with methotrexate. However, genetic polymorphisms affect the pharmacokinetics and dynamics of all the drugs a patient receive as well as the normal tissues tolerance to a given drug exposure. Thus, although high-throughput techniques will allow mapping of tens of thousands of genetic polymorphisms in one run, it will be a major challenge to dissect out which of these have the strongest impact on efficacy and toxicity and hence should be the targets for intervention. This paper discusses the pharmacology of methotrexate and reviews studies on haematological malignancies that have attempted to predict the risk of toxicity by specific clinical or genetic features.
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Affiliation(s)
- Kjeld Schmiegelow
- The Faculty of Medicine, Institute of Gynaecology, Obstetrics and Paediatrics, University of Copenhagen, Copenhagen, Denmark.
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64
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Vlaming ML, Pala Z, van Esch A, Wagenaar E, de Waart DR, van de Wetering K, van der Kruijssen CM, Oude Elferink RP, van Tellingen O, Schinkel AH. Functionally Overlapping Roles of Abcg2 (Bcrp1) and Abcc2 (Mrp2) in the Elimination of Methotrexate and Its Main Toxic Metabolite 7-Hydroxymethotrexate In vivo. Clin Cancer Res 2009; 15:3084-93. [DOI: 10.1158/1078-0432.ccr-08-2940] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Abstract
Purpose: ABCC2 (MRP2) and ABCG2 (BCRP) transport various endogenous and exogenous compounds, including many anticancer drugs, into bile, feces, and urine. We investigated the possibly overlapping roles of Abcg2 and Abcc2 in the elimination of the anticancer drug methotrexate (MTX) and its toxic metabolite 7-hydroxymethotrexate (7OH-MTX).
Experimental Design: We generated and characterized Abcc2;Abcg2-/- mice, and used these to determine the overlapping roles of Abcc2 and Abcg2 in the elimination of MTX and 7OH-MTX after i.v. administration of 50 mg/kg MTX.
Results: Compared with wild-type, the plasma areas under the curve (AUC) for MTX were 1.6-fold and 2.0-fold higher in Abcg2-/- and Abcc2-/- mice, respectively, and 3.3-fold increased in Abcc2;Abcg2-/- mice. The biliary excretion of MTX was 23-fold reduced in Abcc2;Abcg2-/- mice, and the MTX levels in the small intestine were dramatically decreased. Plasma levels of 7OH-MTX were not significantly altered in Abcg2-/- mice, but the areas under the curve were 6.2-fold and even 12.4-fold increased in Abcc2-/- and Abcc2;Abcg2-/- mice, respectively. This indicates that Abcc2 compensates for Abcg2 deficiency but that Abcg2 can only partly compensate for Abcc2 absence. Furthermore, 21-fold decreased biliary 7OH-MTX excretion in Abcc2;Abcg2-/- mice and substantial 7OH-MTX accumulation in the liver and kidney were seen. We additionally found that in the absence of Abcc2, Abcg2 mediated substantial urinary excretion of MTX and 7OH-MTX.
Conclusions: Abcc2 and Abcg2 together are major determinants of MTX and 7OH-MTX pharmacokinetics. Variations in ABCC2 and/or ABCG2 activity due to polymorphisms or coadministered inhibitors may therefore substantially affect the therapeutic efficacy and toxicity in patients treated with MTX.
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Affiliation(s)
| | - Zeliha Pala
- 4Department of Pharmacology, Faculty of Pharmacy, Istanbul University, Istanbul, Turkey
| | | | | | - Dirk R. de Waart
- 3AMC Liver Center, Academic Medical Center, Amsterdam, the Netherlands; and
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65
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Aberrant splicing of folylpolyglutamate synthetase as a novel mechanism of antifolate resistance in leukemia. Blood 2009; 113:4362-9. [DOI: 10.1182/blood-2008-08-173799] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Folylpoly-γ-gluatamate synthetase (FPGS) catalyzes the polyglutamylation and thus intracellular retention of folates and antifolates (eg, methotrexate; MTX) through the addition of multiple glutamate equivalents to their γ-carboxyl residue. Since polyglutamylation of antifolates is crucial for their pharmacological activity in leukemia, loss of FPGS function results in decreased cellular levels of polyglutamylation-dependent antifolates and consequent drug resistance. Whereas resistance to pulse exposure to antifolates is frequently associated with loss of FPGS activity, the underlying molecular mechanism remains elusive. Here we explored the molecular basis of antifolate resistance in human MTX-resistant leukemia cell lines displaying marked loss of FPGS activity. We demonstrate that these MTX-resistant cells exhibit impaired splicing of FPGS mRNA based on intron retention and/or exon skipping, thereby resulting in loss of FPGS function due to premature translation termination. Furthermore, analysis of FPGS transcripts in blood or bone marrow specimens from patients with acute lymphoblastic leukemia revealed exon 12 skipping, both at diagnosis and at relapse, the latter of which occurs after high-dose MTX-containing chemotherapy. These results constitute the first demonstration of the loss of FPGS function via aberrant mRNA splicing, thereby resulting in loss of antifolate retention and drug resistance. The clinical ramifications of these novel findings are discussed.
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Reduced folate carrier and methylenetetrahydrofolate reductase gene polymorphisms: associations with clinical outcome in childhood acute lymphoblastic leukemia. Leukemia 2009; 23:1348-51. [DOI: 10.1038/leu.2009.67] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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67
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Kang MH, Harutyunyan N, Hall CP, Papa RA, Lock RB. Methotrexate and aminopterin exhibit similar in vitro and in vivo preclinical activity against acute lymphoblastic leukaemia and lymphoma. Br J Haematol 2009; 145:389-93. [PMID: 19298590 DOI: 10.1111/j.1365-2141.2009.07631.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Due to the development of neurological toxicity and resistance to methotrexate (MTX), other antifolates have been evaluated for its potential replacement in the treatment of childhood acute lymphoblastic leukaemia (ALL). Aminopterin (AMT) has been suggested to provide clinical advantages over MTX and other antifolates. AMT activity, compared with MTX, was evaluated in ALL and lymphoma preclinical models. The minimum survival fraction at the range of concentrations tested was lower with AMT than with MTX in 3 out of 15 cell lines. Both AMT and MTX significantly extended the event-free survival of mice bearing 3 out of 4 xenografts with equivalent activity.
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Affiliation(s)
- Min H Kang
- Cancer Center, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA.
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68
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69
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Cheok MH, Pottier N, Kager L, Evans WE. Pharmacogenetics in acute lymphoblastic leukemia. Semin Hematol 2009; 46:39-51. [PMID: 19100367 DOI: 10.1053/j.seminhematol.2008.09.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Progress in the treatment of acute lymphoblastic leukemia (ALL) in children has been remarkable, from a disease being lethal four decades ago to current cure rates exceeding 80%. This exemplary progress is largely due to the optimization of existing treatment modalities rather than the discovery of new antileukemic agents. However, despite these high cure rates, the annual number of children whose leukemia relapses after their initial therapy remains greater than that of new cases of most types of childhood cancers. The aim of pharmacogenetics is to develop strategies to personalize treatment and tailor therapy to individual patients, with the goal of optimizing efficacy and safety through better understanding of human genome variability and its influence on drug response. In this review, we summarize recent pharmacogenomic studies related to the treatment of pediatric ALL. These studies illustrate the promise of pharmacogenomics to further advance the treatment of human cancers, with childhood leukemia serving as a paradigm.
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Affiliation(s)
- Meyling H Cheok
- Jean-Pierre Aubert Research Center, INSERM U837, Genomics Core IRCL-IMPRT, Lille, France.
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70
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Yang J, Cheng C, Yang W, Pei D, Cao X, Fan Y, Pounds S, Treviño LR, French D, Campana D, Downing JR, Evans WE, Pui CH, Devidas M, Bowman W, Camitta BM, Willman C, Davies SM, Borowitz MJ, Carroll WL, Hunger SP, Relling MV. Genome-wide interrogation of germline genetic variation associated with treatment response in childhood acute lymphoblastic leukemia. JAMA 2009; 301:393-403. [PMID: 19176441 PMCID: PMC2664534 DOI: 10.1001/jama.2009.7] [Citation(s) in RCA: 183] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
CONTEXT Pediatric acute lymphoblastic leukemia (ALL) is the prototype for a drug-responsive malignancy. Although cure rates exceed 80%, considerable unexplained interindividual variability exists in treatment response. OBJECTIVES To assess the contribution of inherited genetic variation to therapy response and to identify germline single-nucleotide polymorphisms (SNPs) associated with risk of minimal residual disease (MRD) after remission induction chemotherapy. DESIGN, SETTING, AND PATIENTS Genome-wide interrogation of 476,796 germline SNPs to identify genotypes that were associated with MRD in 2 independent cohorts of children with newly diagnosed ALL: 318 patients in St Jude Total Therapy protocols XIIIB and XV and 169 patients in Children's Oncology Group trial P9906. Patients were enrolled between 1994 and 2006 and last follow-up was in 2006. MAIN OUTCOME MEASURES Minimal residual disease at the end of induction therapy, measured by flow cytometry. RESULTS There were 102 SNPs associated with MRD in both cohorts (median odds ratio, 2.18; P < or = .0125), including 5 SNPs in the interleukin 15 (IL15) gene. Of these 102 SNPs, 21 were also associated with hematologic relapse (P < .05). Of 102 SNPs, 21 were also associated with antileukemic drug disposition, generally linking MRD eradication with greater drug exposure. In total, 63 of 102 SNPs were associated with early response, relapse, or drug disposition. CONCLUSION Host genetic variations are associated with treatment response for childhood ALL, with polymorphisms related to leukemia cell biology and host drug disposition associated with lower risk of residual disease.
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Affiliation(s)
- Jun Yang
- St. Jude Children’s Research Hosp., Memphis, TN
| | - Cheng Cheng
- St. Jude Children’s Research Hosp., Memphis, TN
| | | | - Deqing Pei
- St. Jude Children’s Research Hosp., Memphis, TN
| | - Xueyuan Cao
- St. Jude Children’s Research Hosp., Memphis, TN
| | - Yiping Fan
- St. Jude Children’s Research Hosp., Memphis, TN
| | - Stan Pounds
- St. Jude Children’s Research Hosp., Memphis, TN
| | | | | | | | | | | | | | | | - W.P. Bowman
- Cook Children’s Medical Center, Ft. Worth, TX
| | | | | | - Stella M. Davies
- Cincinnati Children’s Hospital and Medical Center, Cincinnati, OH
| | | | | | - Stephen P. Hunger
- The Children’s Hospital and the University of Colorado Cancer Center, Aurora, CO
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Fotoohi AK, Assaraf YG, Moshfegh A, Hashemi J, Jansen G, Peters GJ, Larsson C, Albertioni F. Gene expression profiling of leukemia T-cells resistant to methotrexate and 7-hydroxymethotrexate reveals alterations that preserve intracellular levels of folate and nucleotide biosynthesis. Biochem Pharmacol 2009; 77:1410-7. [PMID: 19426680 DOI: 10.1016/j.bcp.2008.12.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2008] [Revised: 12/30/2008] [Accepted: 12/30/2008] [Indexed: 10/21/2022]
Abstract
In vitro treatment of human T-cell leukemia cells with 7-hydroxymethotrexate, the major metabolite of methotrexate resulted in acquired resistance as a result of the complete loss of folypolyglutamate synthetase (FPGS) activity. This was in contradistinction to the major modality of antifolate resistance of impaired drug transport in leukemia cells exposed to methotrexate. To identify the genes associated with methotrexate and 7-hydroxymethotrexate resistance, we herein explored the patterns of genome-wide expression profiles in these antifolte-resistant leukemia sublines. mRNA levels of the reduced folate carrier, the primary influx transporter of folates and antifolates, were down-regulated more than two-fold in methotrexate-resistant cells. The dramatic loss of FPGS activity in 7-hydroxymethotrexate-resistant cells was associated with alterations in the expression of various genes aimed at preserving reduced folates and/or enhancing purine nucleotide biosynthesis, e.g. methylene tetrahydrofolate reductase, glycinamide ribonucleotide formyltransferase, adenosine deaminase, cystathionine beta synthase, as well as the ATP-dependent folate exporters BCRP/ABCG2 and MRP1/ABCC1. The observed changes in gene expression were generally not paralleled by acquired DNA copy numbers alterations, suggesting transcriptional regulatory mechanisms. Interestingly, gene expression of DNA/RNA metabolism and transport genes were more profoundly altered in methotrexate-resistant subline, whereas in 7-hydroxymethotrexate-resistant cells, the most profoundly affected groups of genes were those encoding for proteins involved in metabolism and cellular proliferation. Thus, the present investigation provides evidence that 7-hydroxymethotrexate induces gene expression alterations and an antifolate resistance modality that are distinct from its parent drug methotrexate.
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Affiliation(s)
- Alan Kambiz Fotoohi
- Department of Oncology and Pathology, Karolinska Institutet, Cancer Center Karolinska, Karolinska University Hospital, Stockholm, Sweden
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72
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Acquired variation outweighs inherited variation in whole genome analysis of methotrexate polyglutamate accumulation in leukemia. Blood 2008; 113:4512-20. [PMID: 19066393 DOI: 10.1182/blood-2008-07-172106] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Methotrexate polyglutamates (MTXPGs) determine in vivo efficacy in acute lymphoblastic leukemia (ALL). MTXPG accumulation differs by leukemic subtypes, but genomic determinants of MTXPG variation in ALL remain unclear. We analyzed 3 types of whole genome variation: leukemia cell gene expression and somatic copy number variation, and inherited single nucleotide polymorphism (SNP) genotypes and determined their association with MTXPGs in leukemia cells. Seven genes (FHOD3, IMPA2, ME2, RASSF4, SLC39A6, SMAD2, and SMAD4) displayed all 3 types of genomic variation associated with MTXPGs (P < .05 for gene expression, P < .01 for copy number variation and SNPs): 6 on chromosome 18 and 1 on chromosome 10. Increased chromosome 18 (P = .002) or 10 (P = .036) copy number was associated with MTXPGs even after adjusting for ALL subtype. The expression of the top 7 genes in leukemia cells accounted for more variation in MTXPGs (46%) than did the expression of the top 7 genes in normal HapMap cell lines (20%). The top 7 inherited SNPs in patients accounted for approximately the same degree of variation (17%) in MTXPGs as did the top 7 SNP genotypes in HapMap cell lines (20%). We conclude that acquired genetic variation in leukemia cells has a stronger influence on MTXPG accumulation than inherited genetic variation.
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73
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Genetic determinants of methotrexate toxicity in rheumatoid arthritis patients: a study of polymorphisms affecting methotrexate transport and folate metabolism. Eur J Clin Pharmacol 2008; 64:1057-68. [DOI: 10.1007/s00228-008-0521-7] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Accepted: 06/02/2008] [Indexed: 10/21/2022]
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74
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Sorich MJ, Pottier N, Pei D, Yang W, Kager L, Stocco G, Cheng C, Panetta JC, Pui CH, Relling MV, Cheok MH, Evans WE. In vivo response to methotrexate forecasts outcome of acute lymphoblastic leukemia and has a distinct gene expression profile. PLoS Med 2008; 5:e83. [PMID: 18416598 PMCID: PMC2292747 DOI: 10.1371/journal.pmed.0050083] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Accepted: 03/03/2008] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Childhood acute lymphoblastic leukemia (ALL) is the most common cancer in children, and can now be cured in approximately 80% of patients. Nevertheless, drug resistance is the major cause of treatment failure in children with ALL. The drug methotrexate (MTX), which is widely used to treat many human cancers, is used in essentially all treatment protocols worldwide for newly diagnosed ALL. Although MTX has been extensively studied for many years, relatively little is known about mechanisms of de novo resistance in primary cancer cells, including leukemia cells. This lack of knowledge is due in part to the fact that existing in vitro methods are not sufficiently reliable to permit assessment of MTX resistance in primary ALL cells. Therefore, we measured the in vivo antileukemic effects of MTX and identified genes whose expression differed significantly in patients with a good versus poor response to MTX. METHODS AND FINDINGS We utilized measures of decreased circulating leukemia cells of 293 newly diagnosed children after initial "up-front" in vivo MTX treatment (1 g/m(2)) to elucidate interpatient differences in the antileukemic effects of MTX. To identify genomic determinants of these effects, we performed a genome-wide assessment of gene expression in primary ALL cells from 161 of these newly diagnosed children (1-18 y). We identified 48 genes and two cDNA clones whose expression was significantly related to the reduction of circulating leukemia cells after initial in vivo treatment with MTX. This finding was validated in an independent cohort of children with ALL. Furthermore, this measure of initial MTX in vivo response and the associated gene expression pattern were predictive of long-term disease-free survival (p < 0.001, p = 0.02). CONCLUSIONS Together, these data provide new insights into the genomic basis of MTX resistance and interpatient differences in MTX response, pointing to new strategies to overcome MTX resistance in childhood ALL. TRIAL REGISTRATIONS Total XV, Therapy for Newly Diagnosed Patients With Acute Lymphoblastic Leukemia, http://www.ClinicalTrials.gov (NCT00137111); Total XIIIBH, Phase III Randomized Study of Antimetabolite-Based Induction plus High-Dose MTX Consolidation for Newly Diagnosed Pediatric Acute Lymphocytic Leukemia at Intermediate or High Risk of Treatment Failure (NCI-T93-0101D); Total XIIIBL, Phase III Randomized Study of Antimetabolite-Based Induction plus High-Dose MTX Consolidation for Newly Diagnosed Pediatric Acute Lymphocytic Leukemia at Lower Risk of Treatment Failure (NCI-T93-0103D).
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Affiliation(s)
- Michael J Sorich
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- Sansom Institute, University of South Australia, Adelaide, Australia
| | - Nicolas Pottier
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- EA2679, Faculté de Médecine de Lille, Pole Recherche, Lille, France
| | - Deqing Pei
- Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Wenjian Yang
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Leo Kager
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- Department of Hematology-Oncology, St. Anna Children's Hospital, Vienna, Austria
| | - Gabriele Stocco
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- Instituto di Ricovero e Cura a Carattere Scientifico, Burlo Garofolo and University of Trieste, Trieste, Italy
| | - Cheng Cheng
- Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - John C Panetta
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- University of Tennessee, Memphis, Tennessee, United States of America
| | - Ching-Hon Pui
- University of Tennessee, Memphis, Tennessee, United States of America
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Mary V Relling
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- University of Tennessee, Memphis, Tennessee, United States of America
- Pharmacogenetics of Anticancer Agents Research Group, National Institutes of Health Pharmacogenetics Research Network, Memphis, Tennessee, United States of America, and Chicago, Illinois, United States of America
| | - Meyling H Cheok
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- University of Tennessee, Memphis, Tennessee, United States of America
| | - William E Evans
- Hematological Malignancies Program and the Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
- University of Tennessee, Memphis, Tennessee, United States of America
- Pharmacogenetics of Anticancer Agents Research Group, National Institutes of Health Pharmacogenetics Research Network, Memphis, Tennessee, United States of America, and Chicago, Illinois, United States of America
- * To whom correspondence should be addressed. E-mail:
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75
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Pharmakogenomik. Monatsschr Kinderheilkd 2008. [DOI: 10.1007/s00112-008-1698-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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76
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Abstract
Acute lymphoblastic leukaemia, a malignant disorder of lymphoid progenitor cells, affects both children and adults, with peak prevalence between the ages of 2 and 5 years. Steady progress in development of effective treatments has led to a cure rate of more than 80% in children, creating opportunities for innovative approaches that would preserve past gains in leukaemia-free survival while reducing the toxic side-effects of current intensive regimens. Advances in our understanding of the pathobiology of acute lymphoblastic leukaemia, fuelled by emerging molecular technologies, suggest that drugs specifically targeting the genetic defects of leukaemic cells could revolutionise management of this disease. Meanwhile, studies are underway to ascertain the precise events that take place in the genesis of acute lymphoblastic leukaemia, to enhance the clinical application of known risk factors and antileukaemic agents, and to identify treatment regimens that might boost the generally low cure rates in adults and subgroups of children with high-risk leukaemia.
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Affiliation(s)
- Ching-Hon Pui
- Department of Oncology, St Jude Children's Research Hospital and University of Tennessee Health Science Center, Memphis, TN 38105, USA.
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77
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van der Straaten RJHM, Wessels JAM, de Vries-Bouwstra JK, Goekoop-Ruiterman YPM, Allaart CF, Bogaartz J, Tiller M, Huizinga TWJ, Guchelaar HJ. Exploratory analysis of four polymorphisms in human GGH and FPGS genes and their effect in methotrexate-treated rheumatoid arthritis patients. Pharmacogenomics 2007; 8:141-50. [PMID: 17286537 DOI: 10.2217/14622416.8.2.141] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The enzyme folylpoly-gamma-glutamase synthethase (FPGS) plays an important role in the intracellular polyglutamation of the disease-modifying antirheumatic drug methotrexate (MTX) and the length of the polyglutamated MTX product correlates with the time that MTX resides in the cell. The glutamates are released from MTX by activity of the enzyme gamma-glutamyl-hydrolase (GGH), thereby allowing the efflux of MTX. GGH 452C>T has been associated with decreased catalytic activity and higher accumulation of long-chain MTX-polyglutamate. However, single nucleotide polymorphisms (SNPs) in FPGS and GGH genes have not yet been explored for association with MTX efficacy or toxicity. We selected for SNPs with frequencies higher than 10% or, in case of FPGS 114G>A, causing an amino acid change with no known frequencies. In this study, frequencies of two SNPs in FPGS (1994A>G and 114G>A, rs10106 and rs10760502, respectively) and GGH genes (452C>T and 16T>C, rs11545078 and rs1800909, respectively), were determined using a newly developed method in rheumatoid arthritis patients (n = 352) and in a group of healthy controls (n = 360). Next, the SNPs were associated with response to MTX in rheumatoid arthritis patients treated with MTX monotherapy. In rheumatoid arthritis patients, allele frequencies of FPGS 1994A>G were 0.534 (A) and 0.466 (G), and for FPGS 114G>A 0.714 (G) and 0.286 (A). Allele frequencies of GGH 16T>C were 0.737 (T) and 0.263 (C) and for GGH 452C>T 0.912 (C) and 0.088 (T). No significant differences in allele frequencies between rheumatoid arthritis patients and healthy controls were found. In addition, the SNPs were not associated with good clinical response to MTX. Only patients with the GGH 16C-allele and one or no copies of the GGH 452C-16T haplotype were associated with good clinical improvement at 3 months upon treatment with MTX. No associations with efficacy at 6 months and MTX-induced toxicity were found. Therefore we conclude that despite the positive association of the GGH 16C-allele and one or no copies of the GGH 452C-16T haplotype with good clinical improvement at 3 months upon treatment with MTX, the tested SNPs in GGH and FPGS genes are suggested not to be clinically important for MTX treatment outcome.
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Affiliation(s)
- R J H M van der Straaten
- Leiden University Medical Center, Department of Clinical Pharmacy and Toxicology, P.O. Box 9600, 2300 RA Leiden, The Netherlands.
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78
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Cunningham L, Aplenc R. Pharmacogenetics of acute lymphoblastic leukemia treatment response. Expert Opin Pharmacother 2007; 8:2519-31. [DOI: 10.1517/14656566.8.15.2519] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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79
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Bhojwani D, Moskowitz N, Raetz EA, Carroll WL. Potential of gene expression profiling in the management of childhood acute lymphoblastic leukemia. Paediatr Drugs 2007; 9:149-56. [PMID: 17523695 DOI: 10.2165/00148581-200709030-00003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Childhood acute lymphoblastic leukemia (ALL) is a heterogeneous disease. Current treatment approaches are tailored according to the clinical features of the host, genotypic features of the leukemic blast, and early response to therapy. Although these approaches have been successful in dramatically improving outcomes, approximately 20% of children with ALL still relapse and many of these children do not have an identifiable adverse risk factor at presentation. Further insights into the biologic basis of the disease may contribute to novel, rational treatment strategies. Childhood ALL has served as an example for demonstrating the feasibility and potential of high-throughput technologies such as global gene expression or transcript profiling. In the last decade or so, utilization of these techniques has grown exponentially. As the methodology undergoes refinement and validation, it is plausible that microarrays may be used in the routine management of childhood ALL in the next few years. This article discusses the numerous applications to date of gene expression profiling in childhood ALL. Multiple investigators have made it evident that microarrays can be used as a single platform for the accurate classification of ALL into the various cytogenetic subtypes. Additional promising utilities include prediction of early response to therapy, overall outcome, and adverse effects. Identification of patients who are predicted to have an unfavorable outcome may allow for early intervention such as intensification of therapy or avoidance of drugs that are associated with specific secondary effects such as therapy-related acute myelogenous leukemia. Knowledge has been gained into pathways contributing to leukemogenesis and chemoresistance. Therapeutic targets have been identified, some of which are entering clinical trials following validation in additional preclinical models. These newer methods of genome analyses complemented by studies involving the proteome as well as host polymorphisms will have a profound impact on the diagnosis and management of childhood ALL.
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Affiliation(s)
- Deepa Bhojwani
- NYU Cancer Institute, Division of Pediatric Hematology, New York University School of Medicine, New York, New York 10016, USA.
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80
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Takenaka K, Morgan JA, Scheffer GL, Adachi M, Stewart CF, Sun D, Leggas M, Ejendal KFK, Hrycyna CA, Schuetz JD. Substrate overlap between Mrp4 and Abcg2/Bcrp affects purine analogue drug cytotoxicity and tissue distribution. Cancer Res 2007; 67:6965-72. [PMID: 17638908 DOI: 10.1158/0008-5472.can-06-4720] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The use of probe substrates and combinations of ATP-binding cassette (ABC) transporter knockout (KO) animals may facilitate the identification of common substrates between apparently unrelated ABC transporters. An unexpectedly low concentration of the purine nucleotide analogue, 9-(2-(phosphonomethoxy)ethyl)-adenine (PMEA), and up-regulation of Abcg2 in some tissues of the Mrp4 KO mouse prompted us to evaluate the possibility that Abcg2 might transport purine-derived drugs. Abcg2 transported and conferred resistance to PMEA. Moreover, a specific Abcg2 inhibitor, fumitremorgin C, both increased PMEA accumulation and reversed Abcg2-mediated PMEA resistance. We developed Mrp4 and Abcg2 double KO mice and used both single KOs of Abcg2 and Mrp4 mice to assess the role of these transporters in vivo. Abcg2 contributed to PMEA accumulation in a variety of tissues, but in some tissues, this contribution was only revealed by the concurrent absence of Mrp4. Abcg2 also transported and conferred resistance to additional purine analogues, such as the antineoplastic, 2-chloro-2'-deoxyadenosine (cladribine) and puromycin, a protein synthesis inhibitor that is often used as a dominant selectable marker. Purine analogues interact with ABCG2 by a site distinct from the prazosin binding site as shown by their inability to displace the substrate analogue and photoaffinity tag [(125)I]iodoarylazidoprazosin. These studies show that Abcg2, like Mrp4, transports and confers resistance to purine nucleoside analogues and suggest that these two transporters work in parallel to affect drug cytotoxicity and tissue distribution. This new knowledge will facilitate an understanding of how Abcg2 and Mrp4, separately and in combination, protect against purine analogue host toxicity as well as resistance to chemotherapy.
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Affiliation(s)
- Kazumasa Takenaka
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105, USA
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81
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Matherly LH, Hou Z, Deng Y. Human reduced folate carrier: translation of basic biology to cancer etiology and therapy. Cancer Metastasis Rev 2007; 26:111-28. [PMID: 17334909 DOI: 10.1007/s10555-007-9046-2] [Citation(s) in RCA: 195] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This review attempts to provide a comprehensive overview of the biology of the physiologically and pharmacologically important transport system termed the "reduced folate carrier" (RFC). The ubiquitously expressed RFC has unequivocally established itself as the major transport system in mammalian cells and tissues for a group of compounds including folate cofactors and classical antifolate therapeutics. Loss of RFC expression or function may have potentially profound pathophysiologic consequences including cancer. For chemotherapeutic antifolates used for cancer such as methotrexate or pemetrexed, synthesis of mutant RFCs or loss of RFC transcripts and proteins results in antifolate resistance due to incomplete inhibition of cellular enzyme targets and insufficient substrate for polyglutamate synthesis. Since RFC was first cloned in 1994, tremendous advances have been made in understanding the complex transcriptional and posttranscriptional regulation of RFC, in identifying structurally and functionally important domains and amino acids in the RFC molecule as a prelude to establishing the mechanism of transport, and in characterizing the molecular defects in RFC associated with loss of transport in antifolate resistant cell line models. Many of the insights gained from laboratory models of RFC portend opportunities for modulating carrier expression in drug resistant tumors, and for designing a new generation of agents with improved transport by RFC or substantially enhanced transport by other folate transporters over RFC. Many of the advances in the basic biology of RFC in cell line models are now being directly applied to human cancers in the clinical setting, most notably pediatric acute lymphoblastic leukemia and osteogenic sarcoma.
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Affiliation(s)
- Larry H Matherly
- Developmental Therapeutics Program, Barbara Ann Karmanos Cancer Institute, The Cancer Biology Graduate Program, Detroit, MI 48201, USA.
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82
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Ge Y, Haska CL, LaFiura K, Devidas M, Linda SB, Liu M, Thomas R, Taub JW, Matherly LH. Prognostic role of the reduced folate carrier, the major membrane transporter for methotrexate, in childhood acute lymphoblastic leukemia: a report from the Children's Oncology Group. Clin Cancer Res 2007; 13:451-7. [PMID: 17255265 DOI: 10.1158/1078-0432.ccr-06-2145] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The value of measuring expression of individual genes relevant to particular chemotherapy drugs and encoding metabolizing enzymes, transporters, or drug targets, as predictors of treatment response and outcome in pediatric acute lymphoblastic leukemia (ALL), remains controversial. EXPERIMENTAL DESIGN In a case-control population of 91 pediatric B-precursor ALL patients [42 relapsed within 4 years (cases) and 49 did not relapse (controls)], we used real-time reverse transcription-PCR to measure transcript levels for 20 genes relevant to chemotherapy with the five major drugs used to treat this disease, including asparaginase, 6-mercaptopurine, methotrexate, prednisone, and vincristine. Results were confirmed in a separate case-control population of 26 patients. RESULTS Only the human reduced folate carrier (hRFC) gene, encoding the major membrane transporter for methotrexate, showed a significant difference in median transcript levels between the 42 cases and the 49 controls (P = 0.0278, Wilcoxon test). Using cutoffs for hRFC expression levels (based on Akaike information criterion), there were statistically significant associations between hRFC transcripts and treatment relapse (P = 0.0052). hRFC-B, corresponding to the major hRFC transcript form in ALL, was also measured by real-time reverse transcription-PCR and was prognostic. The association between treatment relapse and hRFC levels was validated in a separate study population of 14 cases and 12 controls from an earlier case-control study (P = 0.0221). CONCLUSIONS Our results strongly suggest the prognostic importance of hRFC gene expression to treatment outcomes in pediatric ALL. They validate our previous studies of hRFC transcriptional regulation in pediatric ALL and provide further compelling evidence for the critical role for methotrexate in the successful treatment of this disease.
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Affiliation(s)
- Yubin Ge
- Developmental Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 110 East Warren Avenue, Detroit, MI 48201, USA
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83
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Lim U, Wang SS, Hartge P, Cozen W, Kelemen LE, Chanock S, Davis S, Blair A, Schenk M, Rothman N, Lan Q. Gene-nutrient interactions among determinants of folate and one-carbon metabolism on the risk of non-Hodgkin lymphoma: NCI-SEER case-control study. Blood 2007; 109:3050-9. [PMID: 17119116 PMCID: PMC1852210 DOI: 10.1182/blood-2006-07-034330] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2006] [Accepted: 11/12/2006] [Indexed: 12/22/2022] Open
Abstract
We previously reported a lower risk of non-Hodgkin lymphoma (NHL) associated with high consumption of vitamin B6 and methionine, dietary determinants of one-carbon metabolism. Evidence has linked genetic variants involved in one-carbon metabolism to NHL. We investigated 30 polymorphisms in 18 genes for their main effect on NHL among 1141 incident cases and 949 population-based controls and examined gene-nutrient interactions in a subgroup of 386 cases and 319 controls who provided detailed food-frequency information. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for age, sex, and race. We observed a decreased risk of NHL over-all with BHMTEx8+453A>T and increased risk with CBS Ex13+41C>T, FPGS Ex15-263T>C, and SHMT1 Ex12+138C>T and Ex12+236C>T. Furthermore, significant gene-nutrient interactions limited the protective association comparing high versus low vitamin B6 to FPGS Ex15-263T>C CC (OR = 0.22; 95% CL = 0.10-0.52), MTHFS IVS2-1411T>G TT/TG (OR = 0.54; 95% CI = 0.36-0.81), and MTR Ex26-20A>G AA (OR = 0.55; 95% CI = 0.35-0.86) genotypes, and the protective association of methionine to FTHFD Ex10-40G>TGG (OR = 0.63; 95% CI = 0.44-0.91), MTHFR Ex8-62A>C CC (OR = 0.13; 95% CI = 0.04-0.39), and MTRR Ex5+136T>CTT (OR = 0.67; 95% CI = 0.47-0.97) genotypes. Warranting replication, our finding of gene-nutrient interactions in one-carbon metabolism supports their etiologic involvement in lymphomagenesis.
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Affiliation(s)
- Unhee Lim
- Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Rockville, MD 20852, USA.
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84
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Pan G, Elmquist WF. Mitoxantrone permeability in MDCKII cells is influenced by active influx transport. Mol Pharm 2007; 4:475-83. [PMID: 17388607 DOI: 10.1021/mp060083b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mitoxantrone (MXR) is a prototypical substrate for the ABCG2 (bcrp1) efflux transporter and is often used as a positive control in bcrp-mediated transport studies. This study examined processes involved in the cellular accumulation and directional transport of MXR using an in vitro wild-type (WT) and bcrp1-transfected (bcrp1) MDCKII cell model. Compared to 37 degrees C, incubation at 4 degrees C increased MXR accumulation in bcrp1 cells and unexpectedly decreased MXR accumulation in WT MDCKII cells. [3H]-MXR accumulation was concentration dependent in both WT and bcrp1 cells, exhibiting the characteristics of saturable active influx. At tracer concentrations, there was no difference in MXR directional flux between WT and bcrp1 MDCKII cell monolayers, and the A-to-B (apical-to-basolateral) flux was greater than the B-to-A flux in both cell types. However at higher concentration (20 microM), [3H]-MXR directional flux from A to B decreased and B to A increased, revealing the expected efflux process. Therefore, the orientation of the MXR directional flux process is concentration dependent and only at higher concentrations could the difference between WT and bcrp1 MDCKII cells be distinguished. Taken together, these data show that there is a saturable influx transport system on the apical membrane MDCKII cells that is responsible for the active influx of MXR. This is the first report of an active influx transport system for MXR. The expression of the putative MXR influx transporter in selected cell types could lead to misleading results in drug transport assays that screen for bcrp activity. Moreover, the downregulation of the influx transport system could be a heretofore unrecognized mechanism of MXR resistance in tumor cells.
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Affiliation(s)
- Guoyu Pan
- Department of Pharmaceutics, University of Minnesota, 308 Harvard Street SE, Minneapolis, Minnesota 55455, USA
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Ansari M, Krajinovic M. Pharmacogenomics in cancer treatment defining genetic bases for inter-individual differences in responses to chemotherapy. Curr Opin Pediatr 2007; 19:15-22. [PMID: 17224657 DOI: 10.1097/mop.0b013e3280140613] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Pharmacogenomics is evolving rapidly due to the expansion of genomics and proteomics, the emerging technologies, knowledge of the molecular basis of neoplasms and of drug pathways. This article will give an update on the genetic basis of variable therapeutic responses to anticancer agents in children. RECENT FINDINGS The majority of recent findings concern the pharmacogenetics of key components of acute lymphoblastic leukemia treatment, 6-mercaptopurine and methotrexate. This is not surprising given that leukemia is the most common cancer affecting children, accounting for 25-35% of childhood malignancies worldwide with acute lymphoblastic leukemia comprising 80% of leukemia cases. In certain patients treatment fails due to drug resistance, rendering acute lymphoblastic leukemia the leading cause of cancer-related death in children. Most of the studies use a candidate gene approach adding a new body of evidence to existing knowledge. Recent findings relating to other childhood tumors and the potential to optimize treatment of these malignancies are briefly discussed. SUMMARY Interindividual differences in drug responses are an important cause of resistance to treatment and adverse drug reactions. Pharmacogenetics tends to identify the genetic basis of these suboptimal responses allowing traditional treatment to be complemented by genotype-based drug dose adjustment.
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Affiliation(s)
- Marc Ansari
- Research Center Charles Bruneau, CHU Sainte-Justine, Quebec, Canada
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86
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Beesley AH, Palmer ML, Ford J, Weller RE, Cummings AJ, Freitas JR, Firth MJ, Perera KU, de Klerk NH, Kees UR. Authenticity and drug resistance in a panel of acute lymphoblastic leukaemia cell lines. Br J Cancer 2006; 95:1537-44. [PMID: 17117183 PMCID: PMC2360743 DOI: 10.1038/sj.bjc.6603447] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Cell lines are important models for drug resistance in acute lymphoblastic leukaemia (ALL), but are often criticised as being unrepresentative of primary disease. There are also doubts regarding the authenticity of many lines. We have characterised a panel of ALL cell lines for growth and drug resistance and compared data with that published for primary patient specimens. In contrast to the convention that cell lines are highly proliferative, those established in our laboratory grow at rates similar to estimates of leukaemic cells in vivo (doubling time 53–442 h). Authenticity was confirmed by genetic fingerprinting, which also demonstrated the potential stability of long-term cultures. In vitro glucocorticoid resistance correlated well with that measured ex vivo, but all lines were significantly more sensitive to vincristine than primary specimens. Sensitivity to methotrexate was inversely correlated to that of glucocorticoids and L-asparaginase, indicating possible reciprocity in resistance mechanisms. A cell line identified as highly methotrexate resistant (IC50 >8000-fold higher than other lines) was derived from a patient receiving escalating doses of the drug, indicating in vivo selection of resistance as a cause of relapse. Many of these lines are suitable as models to study naturally occurring resistance phenotypes in paediatric ALL.
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Affiliation(s)
- A H Beesley
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - M-L Palmer
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
- Curtin University of Technology School of Pharmacy, Perth, Western Australia
| | - J Ford
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - R E Weller
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - A J Cummings
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - J R Freitas
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - M J Firth
- Division of Biostatistics and Genetic Epidemiology, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - K U Perera
- Division of Biostatistics and Genetic Epidemiology, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - N H de Klerk
- Division of Biostatistics and Genetic Epidemiology, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
| | - U R Kees
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, and Centre for Child Health Research, University of Western Australia, Perth, Australia
- E-mail:
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87
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Skärby TVC, Anderson H, Heldrup J, Kanerva JA, Seidel H, Schmiegelow K. High leucovorin doses during high-dose methotrexate treatment may reduce the cure rate in childhood acute lymphoblastic leukemia. Leukemia 2006; 20:1955-62. [PMID: 16990760 DOI: 10.1038/sj.leu.2404404] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We explored the relationship between time to relapse and different exposure variables (serum methotrexate (S-MTX) 23, 36 and 42 h after start of administration, MTX elimination time and leucovorin (LV) dose) during high-dose MTX (HDM) treatment of 445 children with acute lymphoblastic leukemia. MTX was infused at 5 g/m2 (non-high risk) or 8 g/m2 (high risk) over 24 h, 2-9 times per patient. LV rescue dose was adjusted according to the S-MTX concentration. Time from end of the last HDM to relapse was analyzed by Cox regression analysis with the logarithms of S-MTX and LV dose as exposures. The combined results from all risk groups suggest that high LV dose is related to higher risk for relapse. Doubling of the LV dose increased the relapse risk by 22% (95% confidence interval 1-49%, P = 0.037). High LV doses correlated with high MTX levels at 23, 36 and 42 h and longer elimination time. The results suggest that high doses of LV increase the risk for relapse despite the fact that they were correlated with high MTX levels and longer MTX elimination time. The choice of MTX and LV doses may be regarded as an intricate balance between effect and counter-effect.
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Affiliation(s)
- T V Ch Skärby
- Department of Pediatrics, Lund University Hospital, Lund, Sweden.
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88
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Gadner H, Masera G, Schrappe M, Eden T, Benoit Y, Harrison C, Nachman J, Pui CH. The Eighth International Childhood Acute Lymphoblastic Leukemia Workshop ('Ponte di legno meeting') report: Vienna, Austria, April 27-28, 2005. Leukemia 2006; 20:9-17. [PMID: 16281070 DOI: 10.1038/sj.leu.2404016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The International Acute Lymphoblastic Leukemia Working Group, the so-called 'Ponte di Legno Workshop' has led to substantial progress in international collaboration in leukemia research. On April 27-28, 2005, the 8th Meeting was held in Vienna, Austria, to continue the discussions about special common treatment elements in randomized clinical trials, ethical and clinical aspects of therapy. Furthermore, collaborative projects of clinical relevance with special emphasis on rare genetic subtypes of Childhood ALL were established. The following report summarizes the achievements and aspects of possible future cooperation.
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Affiliation(s)
- H Gadner
- Berlin-Frankfurt-Münster Study Group and St Anna Children's Hospital, Vienna, Austria.
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89
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Cheng Q, Cheng C, Crews KR, Ribeiro RC, Pui CH, Relling MV, Evans WE. Epigenetic regulation of human gamma-glutamyl hydrolase activity in acute lymphoblastic leukemia cells. Am J Hum Genet 2006; 79:264-74. [PMID: 16826517 PMCID: PMC1559484 DOI: 10.1086/505645] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Accepted: 05/02/2006] [Indexed: 12/31/2022] Open
Abstract
Gamma-glutamyl hydrolase (GGH) catalyzes degradation of the active polyglutamates of natural folates and the antifolate methotrexate (MTX). We found that GGH activity is directly related to GGH messenger RNA expression in acute lymphoblastic leukemia (ALL) cells of patients with a wild-type germline GGH genotype. We identified two CpG islands (CpG1 and CpG2) in the region extending from the GGH promoter through the first exon and into intron 1 and showed that methylation of both CpG islands in the GGH promoter (seen in leukemia cells from approximately 15% of patients with nonhyperdiploid B-lineage ALL) is associated with significantly reduced GGH mRNA expression and catalytic activity and with significantly higher accumulation of MTX polyglutamates (MTXPG(4-7)) in ALL cells. Furthermore, methylation of CpG1 was leukemia-cell specific and had a pronounced effect on GGH expression, whereas methylation of CpG2 was common in leukemia cells and normal leukocytes but did not significantly alter GGH expression. These findings indicate that GGH activity in human leukemia cells is regulated by epigenetic changes, in addition to previously recognized genetic polymorphisms and karyotypic abnormalities, which collectively determine interindividual differences in GGH activity and influence MTXPG accumulation in leukemia cells.
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Affiliation(s)
- Qing Cheng
- Hematological Malignancies Program, Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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90
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Abstract
PURPOSE OF REVIEW The cure rate in children with acute lymphoblastic leukemia now exceeds almost 80% in most treatment protocols in industrialized countries. This has mainly been achieved empirically through carefully controlled, randomized clinical trials. Due to relative nonspecific action and narrow therapeutic indices of antileukemic medications, however, current therapy can be associated with significant short and long-term adverse effects, and around 20% of patients will not be cured despite intensified treatment. Pharmacogenomics, which studies the role of inheritance in individual variation in drug disposition and response, could be a useful tool to further improve outcome in this heterogeneous disease by individualization of therapy based on information gained from the genetic 'make-up' of normal host cells and lymphoblastic leukemia cells. RECENT FINDINGS The focus of this review is on recent progress in the field by discussing the results of selected studies in which information from functional genomics, high-throughput molecular analyses, and pharmacodynamics has been integrated to establish pharmacogenomic models. These models may be used to both maximize efficacy and minimize toxicity of existing antileukemic medications, or to identify novel therapeutic targets in lymphoblasts that are resistant to conventional antileukemic drugs. SUMMARY The findings from recent pharmacogenomic studies can be integrated into decision-making in future clinical trials. Thus there is great promise for advancing event-free survival in childhood leukemia in the future.
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Affiliation(s)
- Leo Kager
- St Anna Children's Hospital, Department of Hematology/Oncology, Children's Cancer Research Institute, Vienna, Austria.
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91
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Sterba J, Dusek L, Demlova R, Valik D. Pretreatment Plasma Folate Modulates the Pharmacodynamic Effect of High-Dose Methotrexate in Children with Acute Lymphoblastic Leukemia and Non-Hodgkin Lymphoma: “Folate Overrescue” Concept Revisited. Clin Chem 2006; 52:692-700. [PMID: 16455868 DOI: 10.1373/clinchem.2005.061150] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Abstract
Background: To evaluate the influence of pretreatment plasma folate concentrations on methotrexate exposure in children with acute lymphoblastic leukemia/non-Hodgkin lymphoma treated with high-dose methotrexate, we assessed time profiles of plasma homocysteine, folate, and vitamin B12 concentrations in children treated with high-dose methotrexate with leucovorin rescue.
Methods: We analyzed 98 treatment courses. The study endpoints were to determine how methotrexate exposure is related to homocysteine accumulation and whether it is influenced by pretreatment plasma folate.
Results: Peak concentrations of homocysteine increased from the start of the intravenous infusion through cessation of methotrexate therapy up to time point t42, when this trend was reversed by administration of folinic acid. The area under the curve (AUC) for plasma homocysteine showed decreasing course-to-course tendencies with a statistically significant decrease only between courses 1 and 2 (P ≤0.05), indicating decreased whole-body homocysteine accumulation in response to administration of consecutive methotrexate courses. Therapeutic courses with low initial folate concentrations (≤10 nmol/L) gave significantly higher responses in homocysteine accumulation expressed both as hcysAUC0–66 h and the peak t42 homocysteine concentrations than did courses with initial folate >10 nmol/L. Correspondingly, in the courses with low initial folate, peak plasma concentrations of methotrexate were significantly higher than in courses with high precourse concentrations of plasma folate.
Conclusion: Endogenous pretreatment plasma folate modulates the magnitude of the methotrexate effect, providing support for a “folate overrescue” concept.
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Affiliation(s)
- Jaroslav Sterba
- Department of Pediatric Oncology, University Hospital, Brno, Czech Republic
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92
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Liu M, Ge Y, Payton SG, Aboukameel A, Buck S, Flatley RM, Haska C, Mohammad R, Taub JW, Matherly LH. Transcriptional regulation of the human reduced folate carrier in childhood acute lymphoblastic leukemia cells. Clin Cancer Res 2006; 12:608-16. [PMID: 16428507 DOI: 10.1158/1078-0432.ccr-05-1954] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The transcriptional regulation of the human reduced folate carrier (hRFC), involved in cellular uptake of methotrexate and reduced folates, was studied in childhood acute lymphoblastic leukemia (ALL). The hRFC gene is regulated by six noncoding exons (A1/A2 and A to E) and multiple promoters. In ALL, hRFC-A1/A2 and hRFC-B are the major transcript forms. EXPERIMENTAL DESIGN RNAs from 18 ALL lymphoblast specimens and 10 nonobese diabetic/severe combined immunodeficient ALL xenografts were assayed by real-time reverse transcription-PCR for hRFC-A1/A2 and hRFC-B transcripts and for transcripts encoding USF1, GATA1, Sp1, and Ikaros transcription factors. For the xenografts, gel shift and chromatin immunoprecipitation assays assessed transcription factor binding to the hRFC-A1/A2 and hRFC-B promoters. CpG methylation density within a 334-bp region, including the core hRFC-B promoter, was established by bisulfite sequencing. hRFC-A1/A2 and hRFC-B promoter polymorphisms were assayed by DNA sequencing. RESULTS For the 28 ALLs, hRFC-A1/A2 and hRFC-B transcripts spanned a 546-fold range. By chromatin immunoprecipitation and gel shift assays, binding was confirmed for USF1 and GATA1 for hRFC-A1/A2, and for Sp1, USF1, and Ikaros for hRFC-B. hRFC transcript levels correlated with those for GATA1 and USF1 for hRFC-A1/A2 and with Sp1 and USF1 transcripts for hRFC-B. CpG methylation in ALL did not correlate with hRFC-B transcripts. In 40 ALL and 17 non-ALL specimens, 2 cosegregating high-frequency polymorphisms (T-1309/C-1217 and C-1309/T-1217; allelic frequencies of 36% and 64%, respectively) were detected in the A1/A2 promoter; none were detected in promoter B. The hRFC-A1/A2 polymorphisms only slightly affected promoter activity. CONCLUSIONS Our results show a complex regulation of hRFC in ALL involving the hRFC-A1/A2 and hRFC-B promoters and noncoding exons. Although Sp1, USF1, and GATA1 levels are critical determinants of hRFC transcription in ALL, neither DNA methylation nor promoter polymorphisms contribute to differences in hRFC expression.
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Affiliation(s)
- Mingjun Liu
- Developmental Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 East Warren Avenue, Detroit, MI 48201, USA
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93
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Abstract
The use of combination chemotherapy to cure acute lymphoblastic leukaemia (ALL) in children emerged in the 1980s as a paradigm for curing any disseminated cancer, and many of the therapeutic principles were subsequently applied to the treatment of other disseminated human cancers. Similarly, elucidation of the pharmacogenomics of ALL and its translation into new chemotherapeutic approaches might serve as a model for optimizing the treatment of other human cancers. Germline polymorphisms and gene-expression patterns in ALL cells have been linked to the toxicity and efficacy of chemotherapy for ALL and are beginning to emerge as useful clinical diagnostics.
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Affiliation(s)
- Meyling H Cheok
- St. Jude Children's Research Hospital, Department of Pharmaceutical Sciences, 332 North Lauderdale Street, Memphis, Tennessee 38105, USA
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94
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Hughes LB, Beasley TM, Patel H, Tiwari HK, Morgan SL, Baggott JE, Saag KG, McNicholl J, Moreland LW, Alarcón GS, Bridges SL. Racial or ethnic differences in allele frequencies of single-nucleotide polymorphisms in the methylenetetrahydrofolate reductase gene and their influence on response to methotrexate in rheumatoid arthritis. Ann Rheum Dis 2006; 65:1213-8. [PMID: 16439441 PMCID: PMC1798268 DOI: 10.1136/ard.2005.046797] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The anti-folate drug methotrexate (MTX) is commonly used to treat rheumatoid arthritis. OBJECTIVE To determine the allele frequencies of five common coding single-nucleotide polymorphisms (SNPs) in the methylenetetrahydrofolate reductase (MTHFR) gene in African-Americans and Caucasians with rheumatoid arthritis and controls to assess whether there are differences in allele frequencies among these ethnic or racial groups and whether these SNPs differentially affect the efficacy or toxicity of MTX. METHODS Allele frequencies in the 677, 1298 and 3 additional SNPs in the MTHFR coding region in 223 (193 Caucasians and 30 African-Americans) patients with rheumatoid arthritis who previously participated in one of two prospective clinical trials were characterised, and genotypes were correlated with the efficacy and toxicity of MTX. Another 308 subjects with rheumatoid arthritis who participated in observational studies, one group predominantly Caucasian and the other African-American, as well as 103 normal controls (53 African-Americans and 50 Caucasians) were used to characterise allele frequencies of these SNPs and their associated haplotypes. RESULTS Significantly different allele frequencies were seen in three of the five SNPs and haplotype frequencies between Caucasians and African-Americans. Allele frequencies were similar between patients with rheumatoid arthritis and controls of the same racial or ethnic group. Frequencies of the rs4846051C, 677T and 1298C alleles were 0.33, 0.11 and 0.13, respectively, among African-Americans with rheumatoid arthritis. Among Caucasians with rheumatoid arthritis, these allele frequencies were 0.08 (p<0.001 compared with African-Americans with rheumatoid arthritis), 0.30 (p = 0.002) and 0.34 (p<0.001), respectively. There was no association between SNP alleles or haplotypes and response to MTX as measured by the mean change in the 28-joint Disease Activity Score from baseline values. In Caucasians, the 1298 A (major) allele was associated with a significant increase in MTX-related adverse events characteristic of a recessive genetic effect (odds ratio 15.86, 95% confidence interval 1.51 to 167.01; p = 0.021), confirming previous reports. There was an association between scores of MTX toxicity and the rs4846051 C allele, and haplotypes containing this allele, in African-Americans, but not in Caucasians. CONCLUSIONS : These results, although preliminary, highlight racial or ethnic differences in frequencies of common MTHFR SNPs. The MTHFR 1298 A and the rs4846051 C alleles were associated with MTX-related adverse events in Caucasians and African-Americans, respectively, but these findings should be replicated in larger studies. The rs4846051 SNP, which is far more common in African-Americans than in Caucasians, can also be proved to be a useful ancestry informative marker in future studies on genetic admixture.
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Affiliation(s)
- L B Hughes
- Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, 415 Lyons-Harrison Research Building, Birmingham, AL 35294-0007, USA
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95
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Affiliation(s)
- Ching-Hon Pui
- Department of Hematology and Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105-2794, USA.
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96
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Cole PD, Kamen BA. Delayed neurotoxicity associated with therapy for children with acute lymphoblastic leukemia. ACTA ACUST UNITED AC 2006; 12:174-83. [PMID: 17061283 DOI: 10.1002/mrdd.20113] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Most children diagnosed today with acute lymphoblastic leukemia (ALL) will be cured. However, treatment entails risk of neurotoxicity, causing deficits in neurocognitive function that can persist in the years after treatment is completed. Many of the components of leukemia therapy can contribute to adverse neurologic sequelae, including craniospinal irradiation, nucleoside analogs, corticosteroids, and antifolates. In this review, we describe the characteristic radiographic findings and neurocognitive deficits seen among survivors of childhood ALL. We summarize what is known about the pathophysiology of delayed treatment-related neurotoxicity, with a focus on the toxicity resulting from pharmacologic disruption of folate physiology within the central nervous system. Finally, we suggest testable strategies to ameliorate the symptoms of treatment-related neurotoxicity or decrease its incidence.
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Affiliation(s)
- Peter D Cole
- Department of Pediatrics and Pharmacology, Robert Wood Johnson Medical School/UMDNJ, The Cancer Institute of New Jersey, New Brunswick, New Jersey 08901, USA.
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97
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Abstract
The current enthusiasm for pharmacogenetics draws much of its inspiration from the relatively few examples of polymorphisms that have marked and seemingly clinically relevant effects on drug response. In this regard, pharmacogenetic research has paralleled the study of human disease, which has enjoyed success in identifying mutations underlying mendelian conditions. Progress in deciphering the genetics of complex diseases, involving the interaction of multiple genes with each other and with the environment has been considerably less successful. In most instances, drug responses will probably also prove to be complex, influenced by both the environment and multiple genetic factors. For pharmacogenetics to deliver on its potential, this complexity will need to be recognized and accommodated, both in basic research and in clinical application of pharmacogenetics. As the attention of researchers begins to shift toward more systematic pharmacogenetic investigations, we suggest some priorities and standards for pharmacogenetic research.
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Affiliation(s)
- Anna C Need
- Institute for Genome Sciences & Policy, Center for Population Genomics & Pharmacogenetics, Duke University, 103 Research Drive, DUMC Box 3471, Durham, North Carolina 27710, USA
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98
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Pharmakogenetik. Monatsschr Kinderheilkd 2005. [DOI: 10.1007/s00112-005-1199-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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99
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Pui CH. Quest for effective agents to combat T-cell acute lymphoblastic leukemia. Eur J Cancer 2005; 41:1243-5. [PMID: 15939259 DOI: 10.1016/j.ejca.2005.03.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2005] [Accepted: 03/01/2005] [Indexed: 11/16/2022]
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