Background: Estrogen receptor-positive breast cancer tumors depend on estrogen signaling for their growth and replication and can be treated by anti-estrogen therapy with tamoxifen. Polymorphisms of the CYP2D6 and CYP2C19 genes are associated with an impaired response to tamoxifen. The study objective was to investigate the impact of genetic polymorphisms in CYP2D6 and CYP2C19 on the pharmacokinetics of tamoxifen and its metabolites in Spanish women with estrogen receptor-positive breast cancer who were candidates for tamoxifen therapy.

Methods: We studied 90 women with estrogen receptor-positive breast cancer, using the AmpliChip CYP450 test to determine CYP2D6 and CYP2C19 gene variants. Plasma levels of tamoxifen and its metabolites were quantified by high-performance liquid chromatography.

Results: The CYP2D6 phenotype was extensive metabolizer in 80%, intermediate metabolizer in 12.2%, ultra-rapid metabolizer in 2.2%, and poor metabolizer in 5.6% of patients, and the allele frequency was 35.0% for allele (*)1, 21.0% for *2, and 18.9% for *4. All poor metabolizers in this series were *4/*4, and their endoxifen and 4-hydroxy tamoxifen levels were 25% lower than those of extensive metabolizers. CYP2C19*2 allele, which has been related to breast cancer outcomes, was detected in 15.6% of the studied alleles.

Conclusion: CYP2D6*4/*4 genotype was inversely associated with 4-hydroxy tamoxifen and endoxifen levels. According to these results, CYP2D6 and CYP2C19 genotyping appears advisable before the prescription of tamoxifen therapy.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3675507PMC
http://dx.doi.org/10.7150/ijms.5708DOI Listing

Publication Analysis

Top Keywords

breast cancer
20
cyp2d6 cyp2c19
16
tamoxifen metabolites
12
estrogen receptor-positive
12
receptor-positive breast
12
tamoxifen
9
levels tamoxifen
8
metabolites spanish
8
spanish women
8
polymorphisms cyp2d6
8

Similar Publications

Background: Screening of asymptomatic stage IV breast cancer with brain MRIs is currently not recommended by National Comprehensive Cancer Network (NCCN) Guidelines. The incidence of asymptomatic brain metastasis is not well documented.

Methods: The study is designed as a single arm, phase II trial, with the goal of investigating surveillance brain MRIs in neurologically asymptomatic patients with metastatic breast cancer.

View Article and Find Full Text PDF

Today, cancer has become one of the leading global tragedies. It occurs when a small number of cells in the body mutate, causing some of them to evade the body's immune system and proliferate uncontrollably. Even more irritating is the fact that patients with cancers frequently relapse after conventional chemotherapy and radiotherapy, leading to additional suffering.

View Article and Find Full Text PDF

Background: Colon adenocarcinoma (COAD) is a malignancy with a high mortality rate and complex biological characteristics and heterogeneity, which poses challenges for clinical treatment. Anoikis is a type of programmed cell death that occurs when cells lose their attachment to the extracellular matrix (ECM), and it plays a crucial role in tumor metastasis. However, the specific biological link between anoikis and COAD, as well as its mechanisms in tumor progression, remains unclear, making it a potential new direction for therapeutic strategy research.

View Article and Find Full Text PDF

Introduction: Oncolytic herpes simplex viruses (oHSVs) are a type of biotherapeutic utilized in cancer therapy due to their ability to selectively infect and destroy tumor cells without harming healthy cells. We sought to investigate the functional genomic response and altered metabolic pathways of human cancer cells to oHSV-1 infection and to elucidate the influence of these responses on the relationship between the virus and the cancer cells.

Methods: Two datasets containing gene expression profiles of tumor cells infected with oHSV-1 (G207) and non-infected cells from the Gene Expression Omnibus (GEO) database were processed and normalized using the R software.

View Article and Find Full Text PDF

Background: Breast cancer remains a leading cause of mortality among women, driven by the molecular complexity of its various subtypes. This study aimed to investigate the differential expression of genes and miRNAs involved in the PI3K/AKT/mTOR signaling pathway, a critical regulator of cancer progression.

Methods: We analyzed tumor tissues from five breast cancer subtypes-luminal A, luminal B HER2-negative, luminal B HER2-positive, HER2-positive, and triple-negative breast cancer (TNBC)-and compared them with non-cancerous tissues.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!