Purpose: This study aimed to validate matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS)/Taqman copy number assay (CNA) CYP2D6 genotyping by AmpliChip CYP450 Test for the prediction of tamoxifen metabolizer phenotypes in breast cancer, and to investigate the influence of CYP2D6 variant coverage on genotype-phenotype relationships and tamoxifen outcome.Experimental Design: Hormone receptor-positive postmenopausal breast cancer patients (n = 492) treated with adjuvant tamoxifen, previously analyzed by MALDI-TOF MS/CNA, were reanalyzed by AmpliChip CYP450 Test and validated by independent methods. Cox proportional hazard ratios (HR) were calculated for recurrence of poor (PM) relative to extensive metabolizer (EM) phenotypes with increasing numbers of CYP2D6 variants. Kaplan-Meier distributions were calculated for different phenotype classifications.Results: Concordance was 99.2% to 99.5% for CNA and 99.8% to 100% per CYP2D6 allele (*3, *4, *5, *9, *10, and *41). The prevalence of predicted phenotypes was 1.2% for ultrarapid metabolizer (UM), 37.2% for EM without variant, 43.5% for heterozygous EM, 9.7% for intermediate metabolizer (IM), and 8.3% for PM. Approximately, one third of patients were misclassified based on a *4 analysis only, but inclusion of all reduced-function alleles increased the PM-associated HR from 1.33 (P = 0.58) to 2.87 (P = 0.006). Kaplan-Meier analyses showed highest and lowest clinical benefit for UM and PM with respect to both the AmpliChip-based and a redefined phenotype assignment. The latter revealed significant allele-dose-dependent associations (P = 0.011) and largest effect size (HR PM_EM = 2.77; 95% confidence interval, 1.31-5.89).Conclusions: MALDI-TOF MS/CNA is suitable for accurate CYP2D6 genotyping. For tamoxifen pharmacogenetics, broad CYP2D6 allele coverage is recommended to reduce phenotype misclassification. Classification based on refined EM and reduced-function metabolizers is advisable. Clin Cancer Res; 16(17); 4468-77. ©2010 AACR.Tamoxifen, which is prescribed worldwide for the treatment of estrogen receptor-positive breast cancer, is known to fail in 30% to 50% of patients (1, 2). Underlying mechanisms of tamoxifen resistance include tumorassociated and host genome-associated factors (3). Recent developments in the understanding of the pharmacogenetic relationship between cytochrome P450 2D6 (CYP2D6) polymorphisms and tamoxifen outcome in early breast cancer have shown a strong relationship between a patient's capacity to metabolize tamoxifen and treatment outcome (4), assigning this capacity at least in part to the patient's genetic make-up. Such a relationship has long been suspected based on clinical (5-12) and pharmacokinetic studies (13-15). However, negative and conflicting studies (16-18) point to the need for standardized and uniform study designs including comprehensive CYP2D6 genetic analyses for phenotypic assignment.These complex pharmacogenetic relationships have been underpinned recently by a well-powered mu...
Large-scale metagenome assemblies of human microbiomes have produced a vast catalogue of previously unseen microbial genomes; however, comparatively few microbial genomes derive from other vertebrates. Here, we generated 4374 metagenome assembled genomes (MAGs) from gut samples of 180 predominantly wild animal species representing 5 classes. Combined with existing datasets, we produced 5596 non-redundant, quality MAGs and 1522 species-level genome bins (SGBs). Most SGBs were novel at the species, genus, or family levels, and the majority were enriched in host versus environment metagenomes. Many traits distinguished SGBs enriched in host or environmental biomes, including the number of antimicrobial resistance genes. We identified 1986 diverse and largely novel biosynthetic gene clusters. Gene-based assembly revealed tremendous gene diversity, much of it host or environment specific. Our MAG and gene datasets greatly expand the microbial genome repertoire and provide a broad view of microbial adaptations to life within a living host.
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