|
Advertisement |
|
|
||
 |
|
|||||
|
|||||
|
 |
||||||
|
||||||
|
||||||
|
JCO Early Release, published online ahead of print Feb 1 2010
Received August 20, 2009 Significant Effect of Polymorphisms in CYP2D6 and ABCC2 on Clinical Outcomes of Adjuvant Tamoxifen Therapy for Breast Cancer Patients
From the Laboratories for Pharmacogenetics, Genotyping Development, and Medical Informatics, RIKEN Center for Genomic Medicine, Yokohama; Department of Clinical Pharmacokinetics and Pharmacodynamics, School of Medicine, Keio University; Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo; Department of Surgery, Itoh Surgery and Breast Clinic; Department of Surgery, Yamakawa Breast Clinic, Kochi; First Department of Surgery, Sapporo Medical University; Department of Surgery, Sapporo Breast Surgical Clinic, Sapporo; Department of Breast Surgery, Kansai Rosai Hospotal, Hyogo; Department of Breast Oncology, Shikoku Cancer Center, Ehime; Department of Surgery, Tokushima Breast Care Clinic, Tokushima, Japan; and Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN. * To whom correspondence should be addressed. E-mail: yusuke{at}ims.u-tokyo.ac.jp
Purpose: The clinical efficacy of tamoxifen is suspected to be influenced by the activity of drug-metabolizing enzymes and transporters involved in the formation, metabolism, and elimination of its active forms. We investigated relationships of polymorphisms in transporter genes and CYP2D6 to clinical outcome of patients receiving tamoxifen. Patients and Methods: We studied 282 patients with hormone receptor–positive, invasive breast cancer receiving tamoxifen monotherapy, including 67 patients who have been previously reported. We investigated the effects of allelic variants of CYP2D6 and haplotype-tagging single nucleotide polymorphisms (tag-SNPs) of ABCB1, ABCC2, and ABCG2 on recurrence-free survival using the Kaplan-Meier method and Cox regression analysis. Plasma concentrations of tamoxifen metabolites were measured in 98 patients receiving tamoxifen 20 mg/d. Results: CYP2D6 variants were significantly associated with shorter recurrence-free survival (P = .000036; hazard ratio [HR] = 9.52; 95% CI, 2.79 to 32.45 in patients with two variant alleles v patients without variant alleles). Among 51 tag-SNPs in transporter genes, a significant association was found at rs3740065 in ABCC2 (P = .00017; HR = 10.64; 95% CI, 1.44 to 78.88 in patients with AA v GG genotypes). The number of risk alleles of CYP2D6 and ABCC2 showed cumulative effects on recurrence-free survival (P = .000000055). Patients carrying four risk alleles had 45.25-fold higher risk compared with patients with Conclusion: Our results suggest that polymorphisms in CYP2D6 and ABCC2 are important predictors for the prognosis of patients with breast cancer treated with tamoxifen.
 CiteULike  Complore  Connotea  Del.icio.us  Digg  Facebook  Reddit  Technorati  Twitter What's this?
Related Article
This article has been cited by other articles:
|
||||||||||||
|
|
|||||||||||
|
|||||||||||
|
|
Copyright © 2010 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
|
one risk allele. CYP2D6 variants were associated with lower plasma levels of endoxifen and 4-hydroxytamoxifen (P = .0000043 and .00052), whereas no significant difference was found among ABCC2 genotype groups.
