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Saghafi F, Salehifar E, Ebrahimi P, Shiran MR, Zaboli E, Sohrevardi SM, Jamialahmadi T, Sahebnasagh A, Sahebkar A. Evaluation of the effect of CYP2D6*3, *4,*10, and *17 polymorphisms on the pharmacokinetic of tamoxifen and its metabolites in patients with hormone-positive breast cancer. J Pharm Biomed Anal 2024; 238:115839. [PMID: 37976989 DOI: 10.1016/j.jpba.2023.115839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 10/16/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023]
Abstract
BACKGROUND AND OBJECTIVE A high rate of interindividual variability in response to tamoxifen (TAM) in breast cancer patients with CYP2D6 polymorphism has been reported, which affects the patient's therapeutic outcome. The objective of this study was to investigate the pharmacogenomics of CYP2D6 genotyping in Iranian patients with breast cancer treated with adjuvant TAM. METHODS A peripheral blood sample was obtained to determine the steady-state plasma concentrations of TAM and its metabolites (Endoxifen (EN) and 4-Hydroxytamoxifen (4-OHT)) using high-performance liquid chromatography with fluorescence detection (HPLC-FLU) assay. We detected CYP2D6 * 3, * 4, * 10, and * 17 single nucleotide polymorphisms via polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) method. RESULTS A total of 84 Iranian estrogen receptor‑positive breast cancer patients receiving the daily dose of 20 mg tamoxifen were recruited. Although a consequent decrease in the median EN and 4-OHT concentrations was observed by comparing poor or intermediate metabolizer patients with an extensive metabolizer population, this difference did not reach a significant level. The mean plasma EN concentrations in poor and intermediate metabolizers were 46.1% (95% CI, 7.4-27.8%) and 59.4% (95% CI, 11.9-37.3%) of extensive metabolizer subjects, respectively. Poor and intermediate metabolizers had the mean plasma 4-OHT concentrations that were 46.6% (95% CI, 0.9-61.7%) and 73.2% (95% CI, 2.7-93.1%) of those of subjects who were extensive metabolizer, respectively. CONCLUSIONS The possible role of genotyping in Iranian patients' response to treatment may explain inter-individual differences in the plasma concentrations of active metabolites of TAM.
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Affiliation(s)
- Fatemeh Saghafi
- Department of Clinical Pharmacy, School of Pharmacy, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd, Iran
| | - Ebrahim Salehifar
- Department of Clinical Pharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Pouneh Ebrahimi
- Department of Chemistry, Faculty of Sciences, Golestan University, Gorgan, Iran
| | - Mohammad Reza Shiran
- Department of Pharmacology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Ehsan Zaboli
- Department of Internal Medicine, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Seyed Mojtaba Sohrevardi
- Department of Clinical Pharmacy, School of Pharmacy, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd, Iran
| | - Tannaz Jamialahmadi
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Adeleh Sahebnasagh
- Clinical Research Center, Department of Internal Medicine, School of Medicine, North Khorasan University of Medical Sciences, Bojnurd, Iran.
| | - Amirhossein Sahebkar
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
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Baurley JW, Kjærsgaard A, Zwick ME, Cronin-Fenton DP, Collin LJ, Damkier P, Hamilton-Dutoit S, Lash TL, Ahern TP. Bayesian Pathway Analysis for Complex Interactions. Am J Epidemiol 2020; 189:1610-1622. [PMID: 32639515 DOI: 10.1093/aje/kwaa130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 06/23/2020] [Accepted: 06/30/2020] [Indexed: 12/24/2022] Open
Abstract
Modern epidemiologic studies permit investigation of the complex pathways that mediate effects of social, behavioral, and molecular factors on health outcomes. Conventional analytical approaches struggle with high-dimensional data, leading to high likelihoods of both false-positive and false-negative inferences. Herein, we describe a novel Bayesian pathway analysis approach, the algorithm for learning pathway structure (ALPS), which addresses key limitations in existing approaches to complex data analysis. ALPS uses prior information about pathways in concert with empirical data to identify and quantify complex interactions within networks of factors that mediate an association between an exposure and an outcome. We illustrate ALPS through application to a complex gene-drug interaction analysis in the Predictors of Breast Cancer Recurrence (ProBe CaRe) Study, a Danish cohort study of premenopausal breast cancer patients (2002-2011), for which conventional analyses severely limit the quality of inference.
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Chan CWH, Miaskowski C, McCarthy A, Waye MMY, Yeo W, So WKW, Choi KC, Tsui SKW, Chan JYW. Tamoxifen-related endocrine symptoms in Chinese patients with breast cancer: Study protocol clinical trial (SPIRIT Compliant). Medicine (Baltimore) 2020; 99:e19083. [PMID: 32080081 PMCID: PMC7034730 DOI: 10.1097/md.0000000000019083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Breast cancer is the most prevalent cancer in females and disease recurrence remains a significant problem. To prevent recurrence, tamoxifen is prescribed for at least 5 years. However, among patients who receive tamoxifen, individual responses are highly variable. These responses are affected by the type, frequency, and severity of endocrine symptoms, as well as adherence rates. Polymorphisms in genes involved in the metabolism of tamoxifen (ie, CYP3A4, CYP2D6) may influence responses to tamoxifen. In this study, the inter-relationships among endocrine symptoms, drug adherence, and genetic polymorphisms in Chinese breast cancer patients receiving tamoxifen therapy will be examined. We hypothesize that patients with more severe endocrine symptoms will be less likely to adhere to tamoxifen treatment. In addition, we hypothesize that a relationship will exist between the severity of tamoxifen-induced symptoms and allelic variations in tamoxifen metabolism-related genes. Although many association studies have determined that select genotypes influence the efficacy of tamoxifen, very few studies have investigated for associations between tamoxifen-induced endocrine symptoms and these polymorphisms. OBJECTIVES The aim of this study was to characterize genetic polymorphisms in tamoxifen metabolism-associated genes in Chinese women with breast cancer and to explore the inter-relationships between genetic polymorphisms, endocrine symptoms, and adherence to tamoxifen. METHOD We will conduct a prospective cohort study that follows 200 Chinese women over 18 months and assess treatment-related symptoms and genetic variations. Endocrine symptoms and drug adherence will be determined through interview-administered standardized questionnaires. Polymorphisms in drug metabolism genes will be determined using real-time polymerase chain reaction based genotyping method. Data will be analyzed to determine associations between allelic variations, endocrine symptoms, and adherence. DISCUSSION The proposed study will evaluate for polymorphisms in gene(s) that are associated with tamoxifen-related endocrine symptoms and adherence with tamoxifen. We will explore the relationships between genotypes, endocrine symptoms, and drug adherence in Chinese breast cancer patients. Findings from this study may assist clinicians to identify patients at higher risk for a worse symptom experience and lower adherence rates and enable them to initiate appropriate interventions. In the long term, the findings from this study may be used to develop and test tailored symptom management interventions for these patients.
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Affiliation(s)
- Carmen Wing Han Chan
- The Nethersole School of Nursing, The Chinese University of Hong Kong, Hong Kong
| | | | - Alexandra McCarthy
- School of Nursing, Midwifery and Social Work, University of Queensland, Queensland, Australia
| | - Mary Miu Yee Waye
- The Nethersole School of Nursing, The Chinese University of Hong Kong, Hong Kong
- The Croucher Laboratory for Human Genomics, The Chinese University of Hong Kong
| | | | - Winnie Kwok Wai So
- The Nethersole School of Nursing, The Chinese University of Hong Kong, Hong Kong
| | - Kai Chow Choi
- The Nethersole School of Nursing, The Chinese University of Hong Kong, Hong Kong
| | | | - Judy Yuet Wa Chan
- The Nethersole School of Nursing, The Chinese University of Hong Kong, Hong Kong
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4
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Ghanbari F, Hebert-Losier A, Barry J, Poirier D, Giguere V, Mader S, Philip A. Isolation and functional characterization of a novel endogenous inverse agonist of estrogen related receptors (ERRs) from human pregnancy urine. J Steroid Biochem Mol Biol 2019; 191:105352. [PMID: 30954508 DOI: 10.1016/j.jsbmb.2019.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 03/04/2019] [Accepted: 04/04/2019] [Indexed: 12/23/2022]
Abstract
Estrogen-receptor related receptors (ERRs) which consists of ERRα, ERRβ and ERRγ belong to the orphan nuclear receptor subfamily 3, group B (NR3B) subfamily, and are constitutively active. ERRs have been shown to actively modulate estrogenic responses, and to play an essential role in pregnancy, and are implicated in breast cancer progression. Despite intensive efforts, no endogenous ligand other than the ubiquitous sterol, cholesterol which binds ERRα, has been identified for ERRs so far. The discovery of ligands that bind these orphan receptors will allow the manipulation of this pathway and may lead to novel strategies for the treatment of cancer and other diseases. We previously reported the identification of a novel endogenous estradienolone-like steroid (ED) that is strongly bound to sex hormone binding globulin, in pregnant women. Our recent results show that ED acts as an inverse agonist of ERRα and ERRγ by directly interacting with these receptors, and inhibiting their transcriptional activity. We also demonstrate that ED inhibits the growth of both estrogen receptor-positive (MCF-7) and estrogen receptor-negative (MDA-MB-231) breast cancer cells in a dose dependent manner, while of displaying a little effect on normal epithelial breast cells. Furthermore, the anti-mitogenic effect of ED in breast cancer cells is ERRα-dependent. These data suggest that ED-ERR interaction may represent a novel physiologically relevant hormone response pathway in the human. The finding that ED inhibits both ER negative and ER positive breast cancer cell growth may have important implications in pathophysiology breast cancer.
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Affiliation(s)
- Faegheh Ghanbari
- Division of Plastic Surgery, Department of Surgery, McGill University, Montreal, Canada
| | - Andrea Hebert-Losier
- Division of Plastic Surgery, Department of Surgery, McGill University, Montreal, Canada
| | - Janelle Barry
- Department of Medicine, McGill University, Montreal, Canada
| | - Donald Poirier
- Department of Molecular Medicine, and Centre Hospitalier de l'Université Laval (CHUL), Québec, Canada
| | | | - Sylvie Mader
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Canada
| | - Anie Philip
- Division of Plastic Surgery, Department of Surgery, McGill University, Montreal, Canada; Department of Medicine, McGill University, Montreal, Canada.
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Ariza Márquez YV, Briceño I, Aristizábal F, Niño LF, Yosa Reyes J. Dynamic Effects of CYP2D6 Genetic Variants in a Set of Poor Metaboliser Patients with Infiltrating Ductal Cancer Under Treatment with Tamoxifen. Sci Rep 2019; 9:2521. [PMID: 30792473 PMCID: PMC6385267 DOI: 10.1038/s41598-018-38340-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 12/19/2018] [Indexed: 12/28/2022] Open
Abstract
Breast cancer is a group of multigenic diseases. It is the most common cancer diagnosed among women worldwide and is often treated with tamoxifen. Tamoxifen is catalysed by cytochrome P450 2D6 (CYP2D6), and inter-individual variations in the enzyme due to single nucleotide polymorphisms (SNPs) could alter enzyme activity. We evaluated SNPs in patients from Colombia in South America who were receiving tamoxifen treatment for breast cancer. Allelic diversity in the CYP2D6 gene was found in the studied population, with two patients displaying the poor-metaboliser phenotype. Molecular dynamics and trajectory analyses were performed for CYP2D6 from these two patients, comparing it with the common allelic form (CYP2D6*1). Although we found no significant structural change in the protein, its dynamics differ significantly from those of CYP2D6*1, the effect of such differential dynamics resulting in an inefficient enzyme with serious implications for tamoxifen-treated patients, increasing the risk of disease relapse and ineffective treatment.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Antineoplastic Agents, Hormonal/administration & dosage
- Antineoplastic Agents, Hormonal/metabolism
- Breast Neoplasms/drug therapy
- Breast Neoplasms/genetics
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Carcinoma, Ductal/drug therapy
- Carcinoma, Ductal/genetics
- Carcinoma, Ductal/metabolism
- Carcinoma, Ductal/pathology
- Chemotherapy, Adjuvant
- Cytochrome P-450 CYP2D6/genetics
- Cytochrome P-450 CYP2D6/metabolism
- Female
- Genotype
- Humans
- Inactivation, Metabolic/genetics
- Middle Aged
- Pharmacogenomic Variants/genetics
- Phenotype
- Polymorphism, Single Nucleotide/genetics
- Tamoxifen/administration & dosage
- Tamoxifen/adverse effects
- Tamoxifen/metabolism
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Affiliation(s)
- Yeimy Viviana Ariza Márquez
- Universidad Nacional de Colombia, Instituto de Biotecnología IBUN, Departamento de Farmacia, Bogota, 111321, Colombia
| | - Ignacio Briceño
- Universidad de la Sabana, Facultad de Medicina, Bogota, 140013, Colombia
- Pontificia Universidad Javeriana, Facultad de Medicina, Instituto de Genética Humana IGH, Bogota, 110231, Colombia
| | - Fabio Aristizábal
- Universidad Nacional de Colombia, Instituto de Biotecnología IBUN, Departamento de Farmacia, Bogota, 111321, Colombia
| | - Luis Fernando Niño
- Universidad Nacional de Colombia, Facultad de Ingeniería, Departamento de Ingeniería de Sistemas e Industrial, Bogota, 111321, Colombia
| | - Juvenal Yosa Reyes
- Universidad Simón Bolivar, Facultad de Ciencias Básicas y Biomédicas, Laboratorio de Simulación Molecular y Bioinformática, Barranquilla, 080002, Colombia.
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Brooks JD, Comen EA, Reiner AS, Orlow I, Leong SF, Liang X, Mellemkjær L, Knight JA, Lynch CF, John EM, Bernstein L, Woods M, Doody DR, Malone KE, Bernstein JL. CYP2D6 phenotype, tamoxifen, and risk of contralateral breast cancer in the WECARE Study. Breast Cancer Res 2018; 20:149. [PMID: 30526633 PMCID: PMC6288916 DOI: 10.1186/s13058-018-1083-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 11/19/2018] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Tamoxifen treatment greatly reduces a woman's risk of developing a second primary breast cancer. There is, however, substantial variability in treatment response, some of which may be attributed to germline genetic variation. CYP2D6 is a key enzyme in the metabolism of tamoxifen to its active metabolites, and variants in this gene have been associated with reduced tamoxifen metabolism. The impact of variation on risk of contralateral breast cancer (CBC) is unknown. METHODS Germline DNA from 1514 CBC cases and 2203 unilateral breast cancer controls was genotyped for seven single nucleotide polymorphisms, one three-nucleotide insertion-deletion, and a full gene deletion. Each variant has an expected impact on enzyme activity, which in combination allows for the classification of women as extensive, intermediate, and poor metabolizers (EM, IM, and PM respectively). Each woman was assigned one of six possible diplotypes and a corresponding CYP2D6 activity score (AS): EM/EM (AS = 2), EM/IM (AS = 1.5), EM/PM (AS = 1), IM/IM (AS = 0.75), IM/PM (AS = 0.5), and PM/PM (AS = 0). We also collapsed categories of the AS to generate an overall phenotype (EM, AS ≥ 1; IM, AS = 0.5-0.75; PM, AS = 0). Rate ratios (RRs) and 95% confidence intervals (CIs) for the association between tamoxifen treatment and risk of CBC in our study population were estimated using conditional logistic regression, stratified by AS. RESULTS Among women with AS ≥ 1 (i.e., EM), tamoxifen treatment was associated with a 20-55% reduced RR of CBC (AS = 2, RR = - 0.81, 95% CI 0.62-1.06; AS = 1.5, RR = 0.45, 95% CI 0.30-0.68; and AS = 1, RR = 0.55, 95% CI 0.40-0.74). Among women with no EM alleles and at least one PM allele (i.e., IM and PM), tamoxifen did not appear to impact the RR of CBC in this population (AS = 0.5, RR = 1.08, 95% CI 0.59-1.96; and AS = 0, RR = 1.17, 95% CI 0.58-2.35) (p for homogeneity = - 0.02). CONCLUSION This study suggests that the CYP2D6 phenotype may contribute to some of the observed variability in the impact of tamoxifen treatment for a first breast cancer on risk of developing CBC.
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Affiliation(s)
- Jennifer D. Brooks
- University of Toronto, Dalla Lana School of Public Health Sciences, 155 College St. HSB 676, Toronto, ON M5T 3M7 Canada
| | | | - Anne S. Reiner
- Memorial Sloan Kettering Cancer Center, New York, NY USA
| | - Irene Orlow
- Memorial Sloan Kettering Cancer Center, New York, NY USA
| | - Siok F. Leong
- Memorial Sloan Kettering Cancer Center, New York, NY USA
| | - Xiaolin Liang
- Memorial Sloan Kettering Cancer Center, New York, NY USA
| | | | - Julia A. Knight
- University of Toronto, Dalla Lana School of Public Health Sciences, 155 College St. HSB 676, Toronto, ON M5T 3M7 Canada
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Canada
| | | | - Esther M. John
- Department of Medicine and Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA USA
| | - Leslie Bernstein
- Beckman Research Institute, City of Hope National Medical Centre, Duarte, CA USA
| | - Meghan Woods
- Memorial Sloan Kettering Cancer Center, New York, NY USA
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Landeros-Martínez LL, Glossman-Mitnik D, Flores-Holguín N. Studying the chemical reactivity properties of the target tumor-environment tripeptides NGR (asparagine-glycine-arginine) and RGD (arginine-glycine-aspartic acid) in their interactions with tamoxifen through conceptual density functional theory. J Mol Model 2018; 24:336. [PMID: 30413890 DOI: 10.1007/s00894-018-3868-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 10/31/2018] [Indexed: 11/26/2022]
Abstract
Here, we report theoretical research into the interaction of the drug tamoxifen drug with tripeptides found in the tumor environment-specifically, asparagine-glycine-arginine (NGR) and arginine-glycine-aspartic acid (RGD). Reactivity parameters of these tripeptides were calculated and their intrinsic reactivities and cross-reactivities were analyzed. The interactions of the tripeptides with the nanodiamond-tamoxifen (ND-TAM) complex where the nanodiamond acts as a nanocarrier were also examined theoretically. In addition, their intestinal absorption was predicted based on the polar surface area. The results showed that tamoxifen interacts with RGD, and this interaction remained after the addition of the nanodiamond. An analysis of the chemical hardnesses of the tripeptides was carried out to explore their possible use as synthetic vectors when joined to the nanodiamond. Results indicated that NGR is the most stable of the tripeptides and could be used for active targeting. All calculations were implemented using the conceptual framework of density functional theory.
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Affiliation(s)
- Linda-Lucila Landeros-Martínez
- Laboratorio Virtual NANOCOSMOS, Departamento de Medio Ambiente y Energía, Centro de Investigación en Materiales Avanzados, Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31136, Chihuahua, Chih, Mexico
| | - Daniel Glossman-Mitnik
- Laboratorio Virtual NANOCOSMOS, Departamento de Medio Ambiente y Energía, Centro de Investigación en Materiales Avanzados, Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31136, Chihuahua, Chih, Mexico
| | - Norma Flores-Holguín
- Laboratorio Virtual NANOCOSMOS, Departamento de Medio Ambiente y Energía, Centro de Investigación en Materiales Avanzados, Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31136, Chihuahua, Chih, Mexico.
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Chowdhury N, Vhora I, Patel K, Bagde A, Kutlehria S, Singh M. Development of Hot Melt Extruded Solid Dispersion of Tamoxifen Citrate and Resveratrol for Synergistic Effects on Breast Cancer Cells. AAPS PharmSciTech 2018; 19:3287-3297. [PMID: 30218267 DOI: 10.1208/s12249-018-1111-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 06/20/2018] [Indexed: 02/02/2023] Open
Abstract
Primary standard therapy for ER-positive breast cancer being tamoxifen, newer delivery approach for enhancement of dissolution and therapeutic efficiency of tamoxifen through oral route could be a possible solution. In the present study, we investigated combination of tamoxifen (TAM) with resveratrol (RES) and observed that the combination is effective on MCF-7 breast cancer cells. To ensure co-delivery of the drugs, we explored the hot melt extrusion technique for simultaneously extruding two drugs together in order to enhance their bioavailability. As both are class II drugs with dissolution limited bioavailability, detailed formulation and process parameter analyses were carried out. Detailed characterization using microscopy, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray powder diffraction (XRD) confirmed that both the drugs were molecularly dispersed in the matrix of Soluplus, CremophorRH40, and Poloxamer188, and no interactions between the ingredients were there during hot melt extrusion (HME) process. Dissolution studies confirmed that HME extrudates were able to release drug more rapidly than simple suspension formulation. Further, pharmacokinetic studies in rats were carried out for tamoxifen. Results demonstrated that extrusion significantly increased the tamoxifen oral bioavailability (p < 0.05) (Tmax = 2.00 ± 0.56 h, Cmax = 3.66 ± 1.49 μg/mL, AUC = 39.80 ± 16.24 μg h/mL, MRT = 20.49 ± 5.71) compared to the conventional suspension of tamoxifen (Tmax = 2.00 ± 0.71 h, Cmax = 2.41 ± 0.84 μg/mL, AUC = 12.82 ± 3.99 μg h/mL, MRT = 18.24 ± 5.95 h). In vitro cytotoxicity studies of TAM, RES, and their combination (TAM-RES) were evaluated with MCF7 cells. The combination showed significantly lower IC50 compared to TAM with increasing ratio of RES which is a result of apoptosis. HME-based simultaneous extrusion of TAM and RES formulation provides a suitable formulation strategy for breast cancer treatment and establishes proof of concept for extruding multiple drugs simultaneously for other applications in future.
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MESH Headings
- Administration, Oral
- Animals
- Antineoplastic Agents, Hormonal/administration & dosage
- Antineoplastic Agents, Hormonal/chemistry
- Antineoplastic Agents, Hormonal/metabolism
- Antineoplastic Agents, Phytogenic/administration & dosage
- Antineoplastic Agents, Phytogenic/chemistry
- Antineoplastic Agents, Phytogenic/metabolism
- Antineoplastic Combined Chemotherapy Protocols/administration & dosage
- Antineoplastic Combined Chemotherapy Protocols/chemistry
- Antineoplastic Combined Chemotherapy Protocols/metabolism
- Breast Neoplasms/drug therapy
- Breast Neoplasms/metabolism
- Calorimetry, Differential Scanning/methods
- Chemistry, Pharmaceutical/methods
- Drug Development/methods
- Drug Synergism
- Hot Temperature
- Humans
- MCF-7 Cells
- Rats
- Rats, Sprague-Dawley
- Resveratrol/administration & dosage
- Resveratrol/chemistry
- Resveratrol/metabolism
- Spectroscopy, Fourier Transform Infrared/methods
- Tamoxifen/administration & dosage
- Tamoxifen/chemistry
- Tamoxifen/metabolism
- X-Ray Diffraction/methods
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Affiliation(s)
- Nusrat Chowdhury
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, 32307, USA
| | - Imran Vhora
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, 32307, USA
| | - Ketan Patel
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, 32307, USA
- College of Pharmacy and Health Sciences, St. John's University, Jamaica, New York, 11439, USA
| | - Arvind Bagde
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, 32307, USA
| | - Shallu Kutlehria
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, 32307, USA
| | - Mandip Singh
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, 32307, USA.
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9
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MacLeod AK, McLaughlin LA, Henderson CJ, Wolf CR. Application of Mice Humanized for CYP2D6 to the Study of Tamoxifen Metabolism and Drug-Drug Interaction with Antidepressants. Drug Metab Dispos 2017; 45:17-22. [PMID: 27756789 PMCID: PMC5193068 DOI: 10.1124/dmd.116.073437] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 10/17/2016] [Indexed: 12/12/2022] Open
Abstract
Tamoxifen is an estrogen receptor antagonist used in the treatment of breast cancer. It is a prodrug that is converted by several cytochrome P450 enzymes to a primary metabolite, N-desmethyltamoxifen (NDT), which is then further modified by CYP2D6 to a pharmacologically potent secondary metabolite, 4-hydroxy-N-desmethyltamoxifen (endoxifen). Antidepressants (ADs), which are often coprescribed to patients receiving tamoxifen, are also metabolized by CYP2D6 and evidence suggests that a drug-drug interaction between these agents adversely affects the outcome of tamoxifen therapy by inhibiting endoxifen formation. We evaluated this potentially important drug-drug interaction in vivo in mice humanized for CYP2D6 (hCYP2D6). The rate of conversion of NDT to endoxifen by hCYP2D6 mouse liver microsomes (MLMs) in vitro was similar to that of the most active members of a panel of 13 individual human liver microsomes. Coincubation with quinidine, a CYP2D6 inhibitor, ablated endoxifen generation by hCYP2D6 MLMs. The NDT-hydroxylation activity of wild-type MLMs was 7.4 times higher than that of hCYP2D6, whereas MLMs from Cyp2d knockout animals were inactive. Hydroxylation of NDT correlated with that of bufuralol, a CYP2D6 probe substrate, in the human liver microsome panel. In vitro, ADs of the selective serotonin reuptake inhibitor class were, by an order of magnitude, more potent inhibitors of NDT hydroxylation by hCYP2D6 MLMs than were compounds of the tricyclic class. At a clinically relevant dose, paroxetine pretreatment inhibited the generation of endoxifen from NDT in hCYP2D6 mice in vivo. These data demonstrate the potential of ADs to affect endoxifen generation and, thereby, the outcome of tamoxifen therapy.
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Affiliation(s)
- A Kenneth MacLeod
- Division of Cancer Research, Level 9, Jacqui Wood Cancer Centre, School of Medicine, University of Dundee, Dundee, DD1 9SY, United Kingdom
| | - Lesley A McLaughlin
- Division of Cancer Research, Level 9, Jacqui Wood Cancer Centre, School of Medicine, University of Dundee, Dundee, DD1 9SY, United Kingdom
| | - Colin J Henderson
- Division of Cancer Research, Level 9, Jacqui Wood Cancer Centre, School of Medicine, University of Dundee, Dundee, DD1 9SY, United Kingdom
| | - C Roland Wolf
- Division of Cancer Research, Level 9, Jacqui Wood Cancer Centre, School of Medicine, University of Dundee, Dundee, DD1 9SY, United Kingdom
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Kroiss M, Plonné D, Kendl S, Schirmer D, Ronchi CL, Schirbel A, Zink M, Lapa C, Klinker H, Fassnacht M, Heinz W, Sbiera S. Association of mitotane with chylomicrons and serum lipoproteins: practical implications for treatment of adrenocortical carcinoma. Eur J Endocrinol 2016; 174:343-53. [PMID: 26671975 DOI: 10.1530/eje-15-0946] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 12/15/2015] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Oral mitotane (o,p'-DDD) is a cornerstone of medical treatment for adrenocortical carcinoma (ACC). AIM Serum mitotane concentrations >14 mg/l are targeted for improved efficacy but not achieved in about half of patients. Here we aimed at a better understanding of intestinal absorption and lipoprotein association of mitotane and metabolites o,p'-dichlorodiphenylacetic acid (o,p'-DDA) and o,p'-dichlorodiphenyldichloroethane (o,p'-DDE). DESIGN Lipoproteins were isolated by ultracentrifugation from the chyle of a 29-year-old patient and serum from additional 14 ACC patients treated with mitotane. HPLC was applied for quantification of mitotane and metabolites. We assessed NCI-H295 cell viability, cortisol production, and expression of endoplasmic reticulum (ER) stress marker genes to study the functional consequences of mitotane binding to lipoproteins. RESULTS Chyle of the index patient contained 197 mg/ml mitotane, 53 mg/ml o,p'-DDA, and 51 mg/l o,p'-DDE. Of the total mitotane in serum, lipoprotein fractions contained 21.7±21.4% (VLDL), 1.9±0.8% (IDL), 8.9±5.5% (LDL1), 18.9±9.6% (LDL2), 10.1±4.0% (LDL3), and 26.3±13.0% (HDL2). Only 12.3±5.5% were in the lipoprotein-depleted fraction. DISCUSSION Mitotane content of lipoproteins directly correlated with their triglyceride and cholesterol content. O,p'-DDE was similarly distributed, but 87.9±4.2% of o,p'-DDA found in the HDL2 and lipoprotein-depleted fractions. Binding of mitotane to human lipoproteins blunted its anti-proliferative and anti-hormonal effects on NCI-H295 cells and reduced ER stress marker gene expression. CONCLUSION Mitotane absorption involves chylomicron binding. High concentrations of o,p'-DDA and o,p'-DDE in chyle suggest intestinal mitotane metabolism. In serum, the majority of mitotane is bound to lipoproteins. In vitro, lipoprotein binding inhibits activity of mitotane suggesting that lipoprotein-free mitotane is the therapeutically active fraction.
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Affiliation(s)
- Matthias Kroiss
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Dietmar Plonné
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Sabine Kendl
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Diana Schirmer
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Cristina L Ronchi
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Andreas Schirbel
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Martina Zink
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Constantin Lapa
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Hartwig Klinker
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Martin Fassnacht
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Werner Heinz
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Silviu Sbiera
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
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Xue C, Peng R, Cao Y, Wang S, Shi Y, An X, Xu F, Yuan Z. Ovarian Function, Not Age, Predicts the Benefit from Ovarian Suppression or Ablation for Premenopausal Women with Breast Cancer. PLoS One 2016; 11:e0148849. [PMID: 26866810 PMCID: PMC4750981 DOI: 10.1371/journal.pone.0148849] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 01/25/2016] [Indexed: 01/13/2023] Open
Abstract
The role of adjuvant ovarian suppression or ablation (OS/OA) in premenopausal women with hormone receptor-positive breast cancer remains controversial. The purpose of our study was to examine which patients might benefit from the addition of OS/OA to tamoxifen. We analyzed the data of 2065 premenopausal patients with hormone receptor-positive invasive ductal carcinomas who were treated at Sun Yat-Sen University Cancer Center from 2000 to 2008. The five-year disease-free survival rate (DFSR) and overall survival rate (OSR) were compared by menstrual status and treatment. Compared with patients older than forty years of age, patients younger than forty years old had significant lower DFSRs and OSRs. The addition of OS/OA to tamoxifen increased the DFSR and OSR of patients with normal menstrual cycles after chemotherapy, regardless of their age at diagnosis. Patients with normal menstrual cycles after chemotherapy are the main beneficiaries of an adjuvant OS/OA.
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Affiliation(s)
- Cong Xue
- Department of medical oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
| | - Roujun Peng
- Department of medical oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
| | - Ye Cao
- Department of GCP, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
| | - Shusen Wang
- Department of medical oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
| | - Yanxia Shi
- Department of medical oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
| | - Xin An
- Department of medical oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
| | - Fei Xu
- Department of medical oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
| | - Zhongyu Yuan
- Department of medical oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative innovation center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, People’s Republic of China
- * E-mail:
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Korkmaz F. Commentary on "spectral characterization of the binding and conformational changes of serum albumins upon interaction with an anticancer drug, anastrozole". Spectrochim Acta A Mol Biomol Spectrosc 2015; 138:967-968. [PMID: 25435486 DOI: 10.1016/j.saa.2014.11.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 11/01/2014] [Indexed: 06/04/2023]
Abstract
The manuscript by R. Punith and J. Seetharamappa (http://dx.doi.org/10.1016/j.saa.201202.038) presents the interaction between serum albumin from human (HAS) and from bovine (BSA) with a drug called Anastrozole (AZ). The drug is on the market for treating patients with breast cancer after surgery and for metastasis in women. The study utilizes various spectroscopic techniques such as; fluorescence, synchronous fluorescence, 3D fluorescence measurements, FTIR, CD and UV. Although there are some relatively minor comments on the paper, the main point that needs to be reviewed by the authors is the result of FTIR measurements. Based on the data provided in the text (there is no figure), the protein sample is not in its native state, which makes the data inconvenient to be used in drawing conclusions. Authors are kindly requested to take another look at the FTIR experiments.
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Affiliation(s)
- Filiz Korkmaz
- Atilim University, Physics Unit, Biophysics Laboratory, Ankara 06836, Turkey
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Punith R, Seetharamappa J. Reply to commentary on "spectral characterization of the binding and conformational changes of serum albumins upon interaction with an anticancer drug, anastrozole". Spectrochim Acta A Mol Biomol Spectrosc 2015; 138:969-971. [PMID: 25534415 DOI: 10.1016/j.saa.2014.11.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 11/01/2014] [Indexed: 06/04/2023]
Affiliation(s)
- Reeta Punith
- Department of Chemistry, Karnatak University, Dharwad 580 003, India
| | - J Seetharamappa
- Department of Chemistry, Karnatak University, Dharwad 580 003, India.
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Aurélien BDH, Sylvie B, Alain D, Jérôme G, Yves P. Ecotoxicological risk assessment linked to the discharge by hospitals of bio-accumulative pharmaceuticals into aquatic media: The case of mitotane. Chemosphere 2013; 93:2365-2372. [PMID: 24063751 DOI: 10.1016/j.chemosphere.2013.08.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 07/28/2013] [Accepted: 08/10/2013] [Indexed: 06/02/2023]
Abstract
The release of hospital wastewater into the urban sewer networks contributes to the general contamination of aquatic media by pharmaceutical residues. These residues include bio-accumulative pharmaceuticals that lead to increased risk for ecosystems because they can concentrate in organisms and food chains, and therefore reach toxic levels. In order to assess the ecotoxicological risks linked to this particular category of residues, we have developed a specific method, by combining a theoretical calculation of pollutant concentrations in organisms to estimate Body Residue (BR), and ecotoxicity biomarkers in fish cell lines, enabling the calculation of a Critical Body Residue (CBR). This method finally results in the calculation of a specific risk quotient (Qb=BR/CBR), characterizing the risk linked to this type of pollutant. This method was applied to mitotane, a bio-accumulative pharmaceutical typically found in hospital wastewater, in the framework of an exposure scenario corresponding to the discharge of all the hospital wastewaters into the Rhone River which flows through the city of Lyon, France. This approach leads to risk quotients (Qb and Qbg) much higher than those found with the classical approach, i.e. Q=PEC/PNEC (Predictive Environmental Concentration/Predictive Non Effect Concentration)=0.0006. This difference in the appreciation of risk is important when using cytotoxicity as the criterion for measuring the toxicity of mitotane (Qb=0.056) and it is even greater when the criterion used is genotoxicity (Qbg=6.8). This study must be now consolidated by taking the biomagnification of the pharmaceuticals into consideration.
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Affiliation(s)
- Brackers de Hugo Aurélien
- Université de Lyon, ENTPE, CNRS, UMR 5023 LEHNA, 2 Rue Maurice Audin, 69518 Vaulx-en-Velin, France; Université de Lyon, Faculté de Pharmacie de Lyon, Lyon, France
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15
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Fernández-Santander A, Gaibar M, Novillo A, Romero-Lorca A, Rubio M, Chicharro LM, Tejerina A, Bandrés F. Relationship between genotypes Sult1a2 and Cyp2d6 and tamoxifen metabolism in breast cancer patients. PLoS One 2013; 8:e70183. [PMID: 23922954 PMCID: PMC3726442 DOI: 10.1371/journal.pone.0070183] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 06/16/2013] [Indexed: 02/06/2023] Open
Abstract
Tamoxifen is a pro-drug widely used in breast cancer patients to prevent tumor recurrence. Prior work has revealed a role of cytochrome and sulfotransferase enzymes in tamoxifen metabolism. In this descriptive study, correlations were examined between concentrations of tamoxifen metabolites and genotypes for CYP2D6, CYP3A4, CYP3A5, SULT1A1, SULT1A2 and SULT1E1 in 135 patients with estrogen receptor-positive breast cancer. Patients were genotyped using the Roche-AmpliChip® CYP450 Test, and Real-Time and conventional PCR-RFLP. Plasma tamoxifen, 4-hydroxy-tamoxifen, N-desmethyl-tamoxifen, endoxifen and tamoxifen-N-oxide were isolated and quantified using a high-pressure liquid chromatography-tandem mass spectrometry system. Significantly higher endoxifen levels were detected in patients with the wt/wt CYP2D6 compared to the v/v CYP2D6 genotype (p<0.001). No differences were detected in the remaining tamoxifen metabolites among CYP2D6 genotypes. Patients featuring the SULT1A2*2 and SULT1A2*3 alleles showed significantly higher plasma levels of 4-hydroxy-tamoxifen and endoxifen (p = 0.025 and p = 0.006, respectively), as likely substrates of the SULT1A2 enzyme. Our observations indicate that besides the CYP2D6 genotype leading to tamoxifen conversion to potent hydroxylated metabolites in a manner consistent with a gene-dose effect, SULT1A2 also seems to play a role in maintaining optimal levels of both 4-hydroxy-tamoxifen and endoxifen.
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Affiliation(s)
- Ana Fernández-Santander
- Department of Basic Biomedical Sciences, Faculty of Biomedical Sciences, Cátedra Florencio Tejerina-Universidad Europea de Madrid, Universidad Europea de Madrid, Madrid, Spain.
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Turpeinen M, Uusitalo J, Lehtinen T, Kailajärvi M, Pelkonen O, Vuorinen J, Tapanainen P, Stjernschantz C, Lammintausta R, Scheinin M. Effects of ospemifene on drug metabolism mediated by cytochrome P450 enzymes in humans in vitro and in vivo. Int J Mol Sci 2013; 14:14064-75. [PMID: 23880855 PMCID: PMC3742231 DOI: 10.3390/ijms140714064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 06/27/2013] [Accepted: 06/28/2013] [Indexed: 11/18/2022] Open
Abstract
The objective of these investigations was to determine the possible effects of the novel selective estrogen receptor modulator, ospemifene, on cytochrome P450 (CYP)-mediated drug metabolism. Ospemifene underwent testing for possible effects on CYP enzyme activity in human liver microsomes and in isolated human hepatocytes. Based on the results obtained in vitro, three Phase 1 crossover pharmacokinetic studies were conducted in healthy postmenopausal women to assess the in vivo effects of ospemifene on CYP-mediated drug metabolism. Ospemifene and its main metabolites 4-hydroxyospemifene and 4′-hydroxyospemifene weakly inhibited a number of CYPs (CYP2B6, CYP2C9, CYP2C19, CYP2C8, and CYP2D6) in vitro. However, only CYP2C9 activity was inhibited by 4-hydroxyospemifene at clinically relevant concentrations. Induction of CYPs by ospemifene in cultured human hepatocytes was 2.4-fold or less. The in vivo studies showed that ospemifene did not have significant effects on the areas under the plasma concentration-time curves of the tested CYP substrates warfarin (CYP2C9), bupropion (CYP2B6) and omeprazole (CYP2C19), demonstrating that pretreatment with ospemifene did not alter their metabolism. Therefore, the risk that ospemifene will affect the pharmacokinetics of drugs that are substrates for CYP enzymes is low.
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Affiliation(s)
- Miia Turpeinen
- Department of Pharmacology and Toxicology, University of Oulu, Oulu 90230, Finland; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +358-50-350-5857; Fax: +358-8-537-5347
| | | | - Terhi Lehtinen
- Clinical Research Services Turku, Institute of Biomedicine, Turku 20520, Finland; E-Mails: (T.L.); (M.K.); (M.S.)
| | - Marita Kailajärvi
- Clinical Research Services Turku, Institute of Biomedicine, Turku 20520, Finland; E-Mails: (T.L.); (M.K.); (M.S.)
| | - Olavi Pelkonen
- Department of Pharmacology and Toxicology, University of Oulu, Oulu 90230, Finland; E-Mail:
| | | | | | | | | | - Mika Scheinin
- Clinical Research Services Turku, Institute of Biomedicine, Turku 20520, Finland; E-Mails: (T.L.); (M.K.); (M.S.)
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Gorman GS, Coward L, Darby A, Rasberry B. Effects of herbal supplements on the bioactivation of chemotherapeutic agents. J Pharm Pharmacol 2013; 65:1014-25. [PMID: 23738729 DOI: 10.1111/jphp.12055] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 02/11/2013] [Indexed: 12/17/2022]
Abstract
OBJECTIVES The aim of this study was to investigate the impact of commercially available, over-the-counter herbal supplements (St John's wort, black cohosh and ginger root extract) on the metabolic activation of tamoxifen and irinotecan. METHODS Co-incubation of each drug and supplement combination over a range of concentrations was conducted in human liver microsomes and the decrease in the rate of active metabolite formation was monitored using high-performance liquid chromatography tandem mass spectrometry. Data was analysed using non-linear regression analysis and Dixon plots to determine the dominant mechanism of inhibition and to estimate the Ki and IC50 values of the commercial supplements. KEY FINDINGS The data suggest that black cohosh was the strongest inhibitor tested in this study for both CYP450 and carboxyesterase mediated biotransformation of tamoxifen and irinotecan, respectively, to their active metabolites. St John's wort was a stronger inhibitor compared with ginger root extract for tamoxifen (CYP mediated pathway), while ginger root extract was a stronger inhibitor compared with St John's wort for the carboxyesterase mediated pathway. CONCLUSIONS Commercially available supplements are widely used by patients and their potential impact on the efficacy of the chemotherapy is often unknown. The clinical significance of these results needs to be evaluated in a comprehensive clinical trial.
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Affiliation(s)
- Gregory S Gorman
- McWhorter School of Pharmacy, Samford University, Birmingham, AL 35229, USA.
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Lama G, Papi M, Angelucci C, Maulucci G, Sica G, De Spirito M. Leuprorelin acetate long-lasting effects on GnRH receptors of prostate cancer cells: an atomic force microscopy study of agonist/receptor interaction. PLoS One 2013; 8:e52530. [PMID: 23326338 PMCID: PMC3541369 DOI: 10.1371/journal.pone.0052530] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 11/19/2012] [Indexed: 01/04/2023] Open
Abstract
High cell-surface GnRH receptor (GnRH-R) levels have been shown to have a major influence on the extent of GnRH agonist-mediated tumor growth inhibition. The ability of the GnRH agonist leuprorelin acetate (LA) to induce a post-transcriptional upregulation of GnRH-R at the plasma membrane of androgen-sensitive (LNCaP) and -insensitive (PC-3) prostate cancer (PCa) cells has been previously demonstrated by Western blotting. Here we performed single molecule force spectroscopy by using Atomic Force Microscopy (AFM), which has proven to be a powerful tool allowing for investigation of living cell surface biological features, such as the so far unclear GnRH agonist/receptor interaction. Thus, in the hormone-insensitive PC-3 cells, we characterized the strength of the LA-receptor binding, and the amount and distribution of the functional receptor molecules on the cell surface. The effect of a long and continuous treatment (up to 30 days) with the agonist (10−11 and 10−6 M) on the same parameters was also investigated. A GnRH-R increase was observed, reaching the maximum (∼80%) after 30 days of treatment with the highest dose of LA (10−6 M). The analogue-induced increase in GnRH-R was also demonstrated by Western blotting. In addition, two different receptor bound strengths were detected by AFM, which suggests the existence of two GnRH-R classes. A homogeneous distribution of the unbinding events has been found on untreated and treated PC-3 cell surfaces. The persistence of high receptor levels at the membrane of these living cells may warrant the maintenance of the response to LA also in androgen-unresponsive PCa. Moreover, the determination of ligand/receptor bond strength could shed light on the poorly understood event of LA/GnRH-R interaction and/or address structural/chemical agonist optimizations.
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Affiliation(s)
- Gina Lama
- Istituto di Istologia ed Embriologia, Facoltà di Medicina e Chirurgia “A. Gemelli”, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Massimiliano Papi
- Istituto di Fisica, Facoltà di Medicina e Chirurgia “A. Gemelli”, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Cristiana Angelucci
- Istituto di Istologia ed Embriologia, Facoltà di Medicina e Chirurgia “A. Gemelli”, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Giuseppe Maulucci
- Istituto di Fisica, Facoltà di Medicina e Chirurgia “A. Gemelli”, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Gigliola Sica
- Istituto di Istologia ed Embriologia, Facoltà di Medicina e Chirurgia “A. Gemelli”, Università Cattolica del Sacro Cuore, Roma, Italy
- * E-mail:
| | - Marco De Spirito
- Istituto di Fisica, Facoltà di Medicina e Chirurgia “A. Gemelli”, Università Cattolica del Sacro Cuore, Roma, Italy
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Belikov S, Öberg C, Jääskeläinen T, Rahkama V, Palvimo JJ, Wrange Ö. FoxA1 corrupts the antiandrogenic effect of bicalutamide but only weakly attenuates the effect of MDV3100 (Enzalutamide™). Mol Cell Endocrinol 2013; 365:95-107. [PMID: 23063623 DOI: 10.1016/j.mce.2012.10.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/26/2012] [Accepted: 10/02/2012] [Indexed: 01/04/2023]
Abstract
Prostate cancer growth depends on androgens. Synthetic antiandrogens are used in the cancer treatment. However, antiandrogens, such as bicalutamide (BIC), have a mixed agonist/antagonist activity. Here we compare the antiandrogenic capacity of BIC to a new antiandrogen, MDV3100 (MDV) or Enzalutamide™. By reconstitution of a hormone-regulated enhancer in Xenopus oocytes we show that both antagonists trigger the androgen receptor (AR) translocation to the nucleus, albeit with a reduced efficiency for MDV. Once in the nucleus, both AR-antagonist complexes can bind sequence specifically to DNA in vivo. The forkhead box transcription factor A (FoxA1) is a negative prognostic indicator for prostate cancer disease. FoxA1 expression presets the enhancer chromatin and makes the DNA more accessible for AR binding. In this context the BIC-AR antiandrogenic effect is seriously compromised as demonstrated by a significant chromatin remodeling and induction of a robust MMTV transcription whereas the MDV-AR complex displays a more persistent antagonistic character.
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Affiliation(s)
- S Belikov
- Department of Cell and Molecular Biology, Karolinska Institutet, SE-17177 Stockholm, Sweden
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20
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Punith R, Seetharamappa J. Spectral characterization of the binding and conformational changes of serum albumins upon interaction with an anticancer drug, anastrozole. Spectrochim Acta A Mol Biomol Spectrosc 2012; 92:37-41. [PMID: 22402577 DOI: 10.1016/j.saa.2012.02.038] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 02/01/2012] [Accepted: 02/10/2012] [Indexed: 05/31/2023]
Abstract
The present study employed different optical spectroscopic techniques viz., fluorescence, FTIR, circular dichroism (CD) and UV-vis absorption spectroscopy to investigate the mechanism of interaction of an anticancer drug, anastrozole (AZ) with transport proteins viz., bovine serum albumin (BSA) and human serum albumin (HSA). The drug, AZ quenched the intrinsic fluorescence of protein and the analysis of results revealed the presence of dynamic quenching mechanism. The binding characteristics of drug-protein were computed. The thermodynamic parameters, enthalpy change (ΔH°) and entropy change (ΔS°) were calculated to be +92.99 kJ/mol and +159.18 J/mol/K for AZ-BSA and, +99.43 kJ/mol and +159.19 J/mol/K for AZ-HSA, respectively. These results indicated that the hydrophobic forces stabilized the interaction between the drug and protein. CD, FTIR, absorption, synchronous and 3D fluorescence results indicated that the binding of AZ to protein induced structural perturbation in both serum albumins. The distance, r between the drug and protein was calculated based on the theory of Förster's resonance energy transfer and found to be 5.9 and 6.24 nm, respectively for AZ-BSA and AZ-HSA.
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Affiliation(s)
- Reeta Punith
- Department of Chemistry, Karnatak University, Dharwad, India
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21
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Gilfillan S, Fiorito E, Hurtado A. Functional genomic methods to study estrogen receptor activity. J Mammary Gland Biol Neoplasia 2012; 17:147-53. [PMID: 22588661 DOI: 10.1007/s10911-012-9254-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 05/03/2012] [Indexed: 02/06/2023] Open
Abstract
Estrogen Receptor (ER) is a nuclear receptor that mediates the actions of estrogen and tamoxifen. ER is expressed in a major fraction of human breast cancers. Recently, genomic maps for estrogen- and tamoxifen-ER have been published. Interestingly, estrogen and tamoxifen induce similar genomic interactions and both ligands have been shown to use co-operating factors. The interactions of these co-operating factors within ER regions have impact both on ER-DNA interactions and gene expression regulated by estrogen and tamoxifen. Moreover, the study of chromatin changes induced by these factors has also provided significant insight into our understanding of ER transcriptional regulation. This methods review describes some functional genomic methods to study the influence of both ER ligands and ER co-operating factors. The analysis of protein-DNA interactions and chromatin changes can be explored by using classical and novel methods such as Chromatin Immunoprecipitation (ChIP) or Formaldehyde-Assisted Isolation of Regulatory Elements (FAIRE). This review also explores the properties of each of these methods and the advantages of combining them with high throughput sequencing.
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MESH Headings
- Animals
- Antineoplastic Agents, Hormonal/metabolism
- Antineoplastic Agents, Hormonal/pharmacology
- Breast Neoplasms/drug therapy
- Breast Neoplasms/metabolism
- Cell Line, Tumor
- Chromatin Immunoprecipitation
- Cross-Linking Reagents/chemistry
- DNA-Binding Proteins/chemistry
- DNA-Binding Proteins/metabolism
- Estrogens/metabolism
- Female
- Gene Expression Regulation, Neoplastic/drug effects
- Genomics/methods
- Humans
- Ligands
- Mammary Glands, Human/drug effects
- Mammary Glands, Human/metabolism
- Neoplasm Proteins/chemistry
- Neoplasm Proteins/genetics
- Neoplasm Proteins/metabolism
- Receptors, Estrogen/chemistry
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Regulatory Elements, Transcriptional/drug effects
- Response Elements/drug effects
- Selective Estrogen Receptor Modulators/metabolism
- Selective Estrogen Receptor Modulators/pharmacology
- Tamoxifen/metabolism
- Tamoxifen/pharmacology
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Affiliation(s)
- Siv Gilfillan
- Breast Cancer Research group, Nordic EMBL Partnership, Centre for Molecular Medicine Norway, University of Oslo, Blindern, Oslo, Norway
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22
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Wu AHB, Lorizio W, Tchu S, Lynch K, Gerona R, Ji W, Ruan W, Ruddy KJ, Desantis SD, Burstein HJ, Ziv E. Estimation of tamoxifen metabolite concentrations in the blood of breast cancer patients through CYP2D6 genotype activity score. Breast Cancer Res Treat 2012; 133:677-83. [PMID: 22294487 PMCID: PMC5739025 DOI: 10.1007/s10549-012-1963-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 01/16/2012] [Indexed: 10/14/2022]
Abstract
Tamoxifen, a prodrug used for adjuvant breast cancer therapy, requires conversion to the active metabolite endoxifen through CYP 2D6. We aimed to construct an algorithm to predict endoxifen concentrations based on a patient’s CYP 2D6 genotype, demographic factors, and co-medication use. Eighty-eight women enrolled in the UCSF TamGen II study and 81 women enrolled in a prospective study at Dana-Farber Cancer Institute were included in this analysis. All the women had been on tamoxifen for at least 3 months before blood collection. Demographic information included the patient’s age, race/ethnicity, body mass index (where available), and self-reported and measured medications and herbals that affect 2D6 activity. DNA was extracted and genotyped for 2D6 (Amplichip, Roche Diagnostics). An activity score was calculated based on genotypes and adjusted for use of medications known to inhibit 2D6. Serum was tested for tamoxifen and metabolite concentrations and for the presence of drugs by liquid chromatography/mass spectrometry. Univariate and multivariate regression analysis were computed for age, body mass index, ethnicity, and adjusted activity score to predict tamoxifen metabolite concentrations in the training data-set of UCSF patients, and the resulting algorithm was validated in the Dana-Farber patients. For the training set, the correlation coefficient (r2) for log endoxifen and N-desmethyltamoxifen:endoxifen ratio to activity score, age, and race, were 0.520 and 0.659, respectively; 0.324 and 0.567 for the validation; and 0.396 and 0.615 for both the datasets combined. An algorithm that incorporates genotype and demographic variables can be used to predict endoxifen concentrations for women on tamoxifen therapy. If endoxifen levels are confirmed to be predictive of tamoxifen benefit, then this algorithm may be helpful to determine which women warrant endoxifen testing.
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Affiliation(s)
- Alan H B Wu
- Department of Laboratory Medicine, San Francisco General Hospital, San Francisco, CA 94110, USA.
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23
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Jager NGL, Rosing H, Linn SC, Schellens JHM, Beijnen JH. Importance of highly selective LC-MS/MS analysis for the accurate quantification of tamoxifen and its metabolites: focus on endoxifen and 4-hydroxytamoxifen. Breast Cancer Res Treat 2012; 133:793-8. [PMID: 22388692 PMCID: PMC3362711 DOI: 10.1007/s10549-012-2000-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 02/15/2012] [Indexed: 01/13/2023]
Abstract
The antiestrogenic effect of tamoxifen is mainly attributable to the active metabolites endoxifen and 4-hydroxytamoxifen. This effect is assumed to be concentration-dependent and therefore quantitative analysis of tamoxifen and metabolites for clinical studies and therapeutic drug monitoring is increasing. We investigated the large discrepancies in reported mean endoxifen and 4-hydroxytamoxifen concentrations. Two published LC-MS/MS methods are used to analyse a set of 75 serum samples from patients treated with tamoxifen. The method from Teunissen et al. (J Chrom B, 879:1677-1685, 2011) separates endoxifen and 4-hydroxytamoxifen from other tamoxifen metabolites with similar masses and fragmentation patterns. The second method, published by Gjerde et al. (J Chrom A, 1082:6-14, 2005) however lacks selectivity, resulting in a factor 2-3 overestimation of the endoxifen and 4-hydroxytamoxifen levels, respectively. We emphasize the use of highly selective LC-MS/MS methods for the quantification of tamoxifen and its metabolites in biological samples.
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Affiliation(s)
- N. G. L. Jager
- Department of Pharmacy & Pharmacology, Slotervaart Hospital/The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands
| | - H. Rosing
- Department of Pharmacy & Pharmacology, Slotervaart Hospital/The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands
| | - S. C. Linn
- Department of Medical Oncology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - J. H. M. Schellens
- Department of Clinical Pharmacology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
- Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3508 TB Utrecht, The Netherlands
| | - J. H. Beijnen
- Department of Pharmacy & Pharmacology, Slotervaart Hospital/The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands
- Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3508 TB Utrecht, The Netherlands
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24
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Mertens-Walker I, Baxter RC, Marsh DJ. Gonadotropin signalling in epithelial ovarian cancer. Cancer Lett 2012; 324:152-9. [PMID: 22634496 DOI: 10.1016/j.canlet.2012.05.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 05/15/2012] [Accepted: 05/16/2012] [Indexed: 11/19/2022]
Abstract
Ovarian cancer is the most lethal of all gynecologic malignancies, although its aetiology remains poorly understood. A role for the gonadotropins, follicle-stimulating hormone (FSH) and luteinising hormone (LH), has been implicated in a variety of different aspects of ovarian cancer tumorigenesis, including cellular proliferation, migration and invasion. This review focuses on the latest advances in knowledge concerning signalling pathways and functional consequences of gonadotropin action, including changes in protein-, miRNA- and gene expression, in epithelial ovarian cancer cells.
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Affiliation(s)
- Inga Mertens-Walker
- Hormones and Cancer Division, Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, St. Leonards, New South Wales 2065, Australia
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25
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Coss CC, Jones A, Parke DN, Narayanan R, Barrett CM, Kearbey JD, Veverka KA, Miller DD, Morton RA, Steiner MS, Dalton JT. Preclinical characterization of a novel diphenyl benzamide selective ERα agonist for hormone therapy in prostate cancer. Endocrinology 2012; 153:1070-81. [PMID: 22294742 DOI: 10.1210/en.2011-1608] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Androgen deprivation therapy (ADT) is the mainstay of treatment for advanced prostate cancer. ADT improves overall and disease-free survival rates, but long-term therapy is associated with severe side effects of androgen and estrogen depletion including hot flashes, weight gain, depression, and osteoporosis. Effective hormone reduction can be achieved without estrogen deficiency-related side effects by using therapy with estrogenic compounds. However, cardiovascular complications induced by estrogens coupled with the availability of LHRH agonists led to discontinuation of estrogen use for primary androgen deprivation therapy in the 1980s. New treatments for prostate cancer that improve patient outcomes without the serious estrogen deficiency-related toxicities associated with ADT using LHRH analogs are needed. Herein we describe a novel nonsteroidal selective estrogen receptor-α agonist designed for first-line therapy of advanced prostate cancer that in animal models induces medical castration and minimizes many of the estrogen deficiency-related side effects of ADT. The present studies show that orally administered GTx-758 reversibly suppressed testosterone to castrate levels and subsequently reduced prostate volume and circulating prostate-specific antigen in relevant preclinical models without inducing hot flashes, bone loss, thrombophilia, hypercoagulation, or increasing fat mass.
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Affiliation(s)
- Christopher C Coss
- Preclinical Research and Development, GTx, Inc., 3 North Dunlap Street, Memphis, Tennessee 38163, USA
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26
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Ferraldeschi R, Howell SJ, Thompson AM, Newman WG. Avoidance of CYP2D6 inhibitors in patients receiving tamoxifen. J Clin Oncol 2010; 28:e584-5; author reply e586. [PMID: 20823421 DOI: 10.1200/jco.2010.30.1887] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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27
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28
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Isomura M, Miki Y. [Genomic based approach to individualized cancer therapy]. Nihon Rinsho 2010; 68:1117-1120. [PMID: 20535965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Chemotherapy plays an important role in cancer therapy. The major problem of chemotherapy is that only a part of patients can receive benefit of chemotherapy. The low efficacy of cancer chemotherapy is mostly due to heterogeneity in cancers. Recent advance in molecular biology has made possible to analyze expressions of a large number of genes simultaneously. To identify cancers effective in the chemotherapy, differences in signatures of genes expressions are compared between in chemotherapy effective cancer and in ineffective ones. Such attempts have been applied to molecular diagnostic tools to predict clinical outcome of the cancer. Using such tools, individualization of cancer chemotherapy is now on clinical trial. In this article, we review molecular diagnostic tools focusing on breast cancer therapy.
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Affiliation(s)
- Minoru Isomura
- Department of Cancer Genomics, The Cancer Institute, Japanese Foundation for Cancer Research
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29
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Sideras K, Ingle JN, Ames MM, Loprinzi CL, Mrazek DP, Black JL, Weinshilboum RM, Hawse JR, Spelsberg TC, Goetz MP. Coprescription of tamoxifen and medications that inhibit CYP2D6. J Clin Oncol 2010; 28:2768-76. [PMID: 20439629 PMCID: PMC2881853 DOI: 10.1200/jco.2009.23.8931] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Accepted: 11/18/2009] [Indexed: 12/14/2022] Open
Abstract
Evidence has emerged that the clinical benefit of tamoxifen is related to the functional status of the hepatic metabolizing enzyme cytochrome P450 2D6 (CYP2D6). CYP2D6 is the key enzyme responsible for the generation of the potent tamoxifen metabolite, endoxifen. Multiple studies have examined the relationship of CYP2D6 status to breast cancer outcomes in tamoxifen-treated women; the majority of studies demonstrated that women with impaired CYP2D6 metabolism have lower endoxifen concentrations and a greater risk of breast cancer recurrence. As a result, practitioners must be aware that some of the most commonly prescribed medications coadministered with tamoxifen interfere with CYP2D6 function, thereby reducing endoxifen concentrations and potentially increasing the risk of breast cancer recurrence. After reviewing the published data regarding tamoxifen metabolism and the evidence relating CYP2D6 status to breast cancer outcomes in tamoxifen-treated patients, we are providing a guide for the use of medications that inhibit CYP2D6 in patients administered tamoxifen.
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Affiliation(s)
- Kostandinos Sideras
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - James N. Ingle
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Matthew M. Ames
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Charles L. Loprinzi
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - David P. Mrazek
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - John L. Black
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Richard M. Weinshilboum
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - John R. Hawse
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Thomas C. Spelsberg
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Matthew P. Goetz
- From the Departments of Oncology, Molecular Pharmacology and Experimental Therapeutics, Psychiatry, and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
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30
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de Bruin C, Feelders RA, Waaijers AM, van Koetsveld PM, Sprij-Mooij DM, Lamberts SWJ, Hofland LJ. Differential regulation of human dopamine D2 and somatostatin receptor subtype expression by glucocorticoids in vitro. J Mol Endocrinol 2009; 42:47-56. [PMID: 18852217 DOI: 10.1677/jme-08-0110] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Dopamine agonists (DA) and somatostatin (SS) analogues have been proposed in the treatment of ACTH-producing neuro-endocrine tumours that cause Cushing's syndrome. Inversely, glucocorticoids (GCs) can differentially influence DA receptor D(2) or SS receptor subtype (sst) expression in rodent models. If this also occurs in human neuro-endocrine cells, then cortisol-lowering therapy could directly affect the expression of these target receptors. In this study, we investigated the effects of the GC dexamethasone (DEX) on D(2) and sst expression in three human neuro-endocrine cell lines: BON (carcinoid) and TT (medullary thyroid carcinoma) versus DMS (small cell lung cancer), which is severely GC resistant. In BON and TT, sst(2) mRNA was strongly down-regulated in a dose-dependent manner (IC(50) 0.84 nM and 0.16 nM), whereas sst(5) and especially D(2) were much more resistant to DEX treatment. Sst(2) down-regulation was abrogated by a GC receptor antagonist and reversible in time upon GC withdrawal. At the protein level, DEX also induced a decrease in the total number of SS (-52%) and sst(2)-specific (-42%) binding sites. Pretreatment with DEX abrogated calcitonin inhibition by sst(2)-preferring analogue octreotide in TT. In DMS, DEX did not cause significant changes in the expression of these receptor subtypes. In conclusion, we show that GCs selectively down-regulate sst(2), but not D(2) and only to a minor degree sst(5) in human neuro-endocrine BON and TT cells. This mechanism may also be responsible for the low expression of sst(2) in corticotroph adenomas and underwrite the current interest in sst(5) and D(2) as possible therapeutic targets for a medical treatment of Cushing's disease.
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Affiliation(s)
- C de Bruin
- Division of Endocrinology, Department of Internal Medicine, Erasmus Medical Center, 's Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands.
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31
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Abstract
A number of studies have reported on the unusual pharmacological behavior of type I antiestrogens, such as tamoxifen. These agents display mixed agonist/antagonist activity in a dose-, cell-, and tissue-specific manner. Consequently, many efforts have been made to develop so-called 'pure' antiestrogens that lack mixed agonist/antagonist activity. The recent report of the structure of estrogen receptor (ER) beta with a second molecule of 4-hydroxytamoxifen (HT) bound in the coactivator-binding surface of the ligand-binding domain (LBD) represents the first direct example of a second ER ligand-binding site and provides insight into the possible origin of mixed agonist/antagonist activity of type I antiestrogens. In this review, we summarize the biological reports leading up to the structural conformation of a second ER ligand-binding site, compare the ERbeta LBD structure bound with two HT molecules to other ER structures, and discuss the potential for small molecular inhibitors designed to directly inhibit ER-coactivator and, more generally, nuclear receptor (NR)-coactivator interactions. The studies support a departure from the traditional paradigm of drug targeting to the ligand-binding site, to that of a rational approach targeting a functionally important surface, namely the NR coactivator-binding (activation function-2) surface. Furthermore, we provide evidence supporting a reevaluation of the strict interpretation of the agonist/antagonist state with respect to the position of helix 12 in the NR LBD.
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Affiliation(s)
- Douglas J Kojetin
- Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, 3125 Eden Avenue, Cincinnati, Ohio 45267-0521, USA
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32
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Gaston C, Kolesar J. Clinical significance of CYP2D6 polymorphisms and tamoxifen in women with breast cancer. Clin Adv Hematol Oncol 2008; 6:825-833. [PMID: 19194367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Tamoxifen has been used as adjuvant hormonal therapy for estrogen receptor positive breast cancer for over 30 years and is also widely used for the treatment of metastatic breast cancer. Tamoxifen is metabolized to its more active form by cytochrome P450 2D6 (CYP2D6); decreases in CYP2D6 activity, either by inactivating polymorphisms or drug interactions, can reduce concentrations of tamoxifen's active metabolites. Clinical studies demonstrate that breast cancer patients treated with adjuvant tamoxifen who have decreased CYP2D6 due to genetic polymorphisms or drug interactions may have an increased risk of recurrence and reductions in disease-free survival. Pharmacogenetic testing is currently available to predict CYP2D6 phenotypes and individualize tamoxifen therapy.
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Affiliation(s)
- Cindy Gaston
- University of Wisconsin Hospitals and Clinics, Madison, WI 53792, USA
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33
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Sofianos ZD, Katsila T, Kostomitsopoulos N, Balafas V, Matsoukas J, Tselios T, Tamvakopoulos C. In vivo evaluation and in vitro metabolism of leuprolide in mice--mass spectrometry-based biomarker measurement for efficacy and toxicity. J Mass Spectrom 2008; 43:1381-1392. [PMID: 18438975 DOI: 10.1002/jms.1416] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The study of pharmacologically active peptides is central for the understanding of cancer and the development of novel therapeutic approaches. In this context, both qualitative and quantitative determination of bioactive peptides in biological fluids/tissues and their effect on endogenous factors (e.g. hormones) are of great importance. A mass spectrometry-based approach was developed and applied towards the measurement of leuprolide, a peptide drug for the treatment of prostate cancer, in mouse plasma. High-pressure liquid chromatography coupled to a hybrid quadrupole linear ion trap (QqLIT) mass spectrometer, a platform that combines the benefits of triple QqLIT instruments, was employed for the study. Using the described methodology, we established that picomolar concentrations of leuprolide could be measured in mouse plasma (limit of quantification of 0.1 ng/ml). In order to optimize pharmacokinetic properties of analogs of leuprolide, a facile in vivo mouse model was developed and leuprolide concentrations were determined in mouse plasma following intraperitoneal administration. In the same animal model, we demonstrated the versatility of the described MS-based approach by the determination of plasma concentrations of testosterone, an established biomarker for the treatment of prostate cancer. Following dosing with leuprolide, circulating testosterone was increased significantly in comparison to vehicle-treated mice. Finally, in vitro metabolism of leuprolide was evaluated by incubation of leuprolide with mouse kidney membranes, followed by identification of major metabolites by MS. Such studies provide the framework for future evaluation of novel leuprolide analogs with potential therapeutic advantages.
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Affiliation(s)
- Zacharias D Sofianos
- Division of Pharmacology-Pharmacotechnology, Biomedical Research Foundation, Academy of Athens, Athens 11527, Greece
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34
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Buclin T, Colombo S, Biollaz J. [Pharmacogenetic testing: soon before every prescription?]. Rev Med Suisse 2008; 4:1666-1670. [PMID: 18767293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Genetic polymorphisms have currently been described in more than 200 systems affecting pharmacological responses (cytochromes P450, conjugation enzymes, transporters, receptors, effectors of response, protection mechanisms, determinants of immunity). Pharmacogenetic testing, i.e. the profiling of individual patients for such variations, is about to become largely available. Recent progress in the pharmacogenetics of tamoxifen, oral anticoagulants and anti-HIV agents is reviewed to discuss critically their potential impact on prescription and contribution/limits for improving rational and safe use of pharmaceuticals. Prospective controlled trials are required to evaluate large-scale pharmacogenetic testing in therapeutics. Ethical, social and psychological issues deserve particular attention.
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Affiliation(s)
- Thierry Buclin
- Division de pharmacologie et toxicologie cliniques, CHUV, 1011 Lausanne
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35
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Velentzis LS, Woodside JV, Cantwell MM, Leathem AJ, Keshtgar MR. Do phytoestrogens reduce the risk of breast cancer and breast cancer recurrence? What clinicians need to know. Eur J Cancer 2008; 44:1799-806. [PMID: 18614351 DOI: 10.1016/j.ejca.2008.05.019] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2008] [Revised: 05/26/2008] [Accepted: 05/29/2008] [Indexed: 12/15/2022]
Abstract
Oestrogen is an important determinant of breast cancer risk. Oestrogen-mimicking plant compounds called phytoestrogens can bind to oestrogen receptors and exert weak oestrogenic effects. Despite this activity, epidemiological studies suggest that the incidence of breast cancer is lower in countries where the intake of phytoestrogens is high, implying that these compounds may reduce breast cancer risk, and possibly have an impact on survival. Isoflavones and lignans are the most common phytoestrogens in the diet. In this article, we present findings from human observational and intervention studies related to both isoflavone and lignan exposure and breast cancer risk and survival. In addition, the clinical implications of these findings are examined in the light of a growing dietary supplement market. An increasing number of breast cancer patients seek to take supplements together with their standard treatment in the hope that these will either prevent recurrence or treat their menopausal symptoms. Observational studies suggest a protective effect of isoflavones on breast cancer risk and the case may be similar for increasing lignan consumption although evidence so far is inconsistent. In contrast, short-term intervention studies suggest a possible stimulatory effect on breast tissue raising concerns of possible adverse effects in breast cancer patients. However, owing to the dearth of human studies investigating effects on breast cancer recurrence and survival the role of phytoestrogens remains unclear. So far, not enough clear evidence exists on which to base guidelines for clinical use, although raising patient awareness of the uncertain effect of phytoestrogens is recommended.
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Affiliation(s)
- Louiza S Velentzis
- University College London, Department of Surgery, Breast Cancer Research Group, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ, UK.
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Mao JW, Wang LW, Jacob T, Sun XR, Li H, Zhu LY, Li P, Zhong P, Nie SH, Chen LX. Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells. Cell Res 2007; 15:371-8. [PMID: 15916723 DOI: 10.1038/sj.cr.7290304] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5'-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of non-migrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells.
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Affiliation(s)
- Jian Wen Mao
- Laboratory of Cell Biology, Guangdong Medical College, Zhanjiang, China
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37
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Han L, Yang D, Kundra V. Signaling can be uncoupled from imaging of the somatostatin receptor type 2. Mol Imaging 2007; 6:427-437. [PMID: 18053413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
Endogenous and exogenous somatostatin receptors are commonly targeted for imaging using radiopharmaceutical analogues of somatostatin. Ligand binding activates receptor-mediated signaling. We assessed whether somatostatin receptor type 2A (SSTR2A) imaging can be uncoupled from signal transduction. In both human fibrosarcoma (HT1080) and human embryonic kidney (HEK293) cells, reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay found similar levels of expression of hemagglutinin A tagged SSTR2A (HA-SSTR2A) or the same fusion protein with a deletion of the C-terminus beyond amino acid 314 (HA-SSTR2Delta314). Scatchard analysis demonstrated similar degrees of ligand binding by the wild-type or mutant receptor to (111)In-octreotide in both cell pairs. Cyclic guanosine monophosphate (cGMP) production and inhibition of forskolin-induced cylic adenosine monophosphate (cAMP) production were evaluated at the signaling level, and growth inhibition was evaluated at the cellular level before and after stimulation. Unlike wild-type receptor, HA-SSTR2Delta314 was deficient in inhibiting forskolin-induced cAMP production (p < .05) and in inciting cGMP (p < .05) production; furthermore, at the cellular level, HA-SSTR2Delta314 was deficient in inhibiting cell proliferation (p < .05). Yet tumors expressing HA-SSTR2Delta314 could be imaged in vivo. Thus, in vivo imaging of SSTR2 can be uncoupled from cAMP and cGMP signaling as well as growth inhibition.
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Affiliation(s)
- Lin Han
- Department of Experimental Diagnostic Imageing, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
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Hot flashes may be a good sign in women taking tamoxifen. Mayo Clin Womens Healthsource 2007; 11:3. [PMID: 17898683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
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39
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Jordan VC. New insights into the metabolism of tamoxifen and its role in the treatment and prevention of breast cancer. Steroids 2007; 72:829-42. [PMID: 17765940 PMCID: PMC2740485 DOI: 10.1016/j.steroids.2007.07.009] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Revised: 07/13/2007] [Accepted: 07/20/2007] [Indexed: 12/13/2022]
Abstract
The metabolism of tamoxifen is being redefined in the light of several important pharmacological observations. Recent studies have identified 4-hydroxy N-desmethyltamoxifen (endoxifen) as an important metabolite of tamoxifen necessary for antitumor actions. The metabolite is formed through the enzymatic product of CYP2D6 which also interacts with specific selective serotonin reuptake inhibitors (SSRIs) used to prevent the hot flashes observed in up to 45% of patients taking tamoxifen. Additionally, the finding that enzyme variants of CYP2D6 do not promote the metabolism of tamoxifen to endoxifen means that significant numbers of women might not receive optimal benefit from tamoxifen treatment. Clearly these are particularly important issues not only for breast cancer treatment but also for selecting premenopausal women, at high risk for breast cancer, as candidates for chemoprevention using tamoxifen.
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Affiliation(s)
- V Craig Jordan
- Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111-2497, USA.
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40
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Abstract
Tamoxifen continues to be a standard endocrine therapy for the prevention and treatment of estrogen receptor (ER)-positive breast cancer. Tamoxifen can be considered a classic "pro-drug," requiring metabolic activation to elicit pharmacological activity. CYP2D6 is the rate-limiting enzyme catalyzing the conversion of tamoxifen into metabolites with significantly greater affinity for the ER and greater ability to inhibit cell proliferation. Both genetic and environmental (drug-induced) factors that alter CYP2D6 enzyme activity directly affect the concentrations of the active tamoxifen metabolites and the outcomes of patients receiving adjuvant tamoxifen. The a priori knowledge of the pharmacogenetic variation known to abrogate CYP2D6 enzyme activity may provide a means by which the hormonal therapy of breast cancer can be individualized.
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Affiliation(s)
- M P Goetz
- Department of Oncology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
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Abstract
Two thirds of breast cancers express the estrogen receptor (ER), which contributes to tumor development and progression. ER-targeted therapy is therefore widely used in breast cancer to inhibit signaling through ER and disrupt breast cancer growth. This therapeutic strategy, particularly using the antiestrogen tamoxifen, is proven to increase the cure rates in early breast cancer, improve patient outcomes in advanced disease, and reduce breast cancer incidence in the prevention setting. Despite the recent integration of more powerful endocrine agents into breast cancer care, resistance to all forms of endocrine therapy remains a major problem. New insight into ER biology and progress in understanding resistance mechanisms, mediated by molecular crosstalk between ER and various growth factor signaling pathways, are generating tremendous promise for new therapeutic opportunities to target resistance and improve breast cancer disease outcomes.
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Affiliation(s)
- Suleiman Massarweh
- Department of Medicine, Markey Cancer Center, University of Kentucky, Lexington, Kentucky 40536, USA.
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Sommer P, Le Rouzic P, Gillingham H, Berry A, Kayahara M, Huynh T, White A, Ray DW. Glucocorticoid receptor overexpression exerts an antisurvival effect on human small cell lung cancer cells. Oncogene 2007; 26:7111-21. [PMID: 17496926 DOI: 10.1038/sj.onc.1210524] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Small cell lung cancer (SCLC) is an aggressive tumour with an abysmal prognosis. These cancers are characteristically resistant to glucocorticoid (Gc) action, owing to impaired expression of the glucocorticoid receptor (GR). We identified reduced GR expression in human SCLC cell lines, compared to a non-SCLC cell line. The SCLC cells also showed no Gc inhibition of proliferation, in contrast to non-SCLC cells. Retroviral overexpression of GR resulted in significantly increased cell death, which was partially blocked by the GR antagonist, RU486. Indeed, in cells sorted for GR expression, there was rapid, near complete loss of live cells by 72 h, in contrast to control cells that proliferated as expected. Flow cytometry using Annexin V revealed that cell death was by apoptosis. In addition, confocal analysis of fixed cells showed that cells overexpressing GR displayed a significant increase in fragmenting apoptotic nuclei. Microarray studies showed that transgenic GR expression upregulated the proapoptotic genes, BAD and BAX. We have, therefore, identified a profound apoptotic effect of GR in SCLC cells, which may explain the low levels of endogenous GR in SCLC cells. Understanding how GR overexpression leads to apoptotic cell death in SCLC cells may uncover new therapeutic strategies.
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Affiliation(s)
- P Sommer
- Faculty of Medical and Human Sciences, Department of Medicine, Centre for Molecular Medicine and Endocrine Sciences Research Group, University of Manchester, Manchester, UK
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Kang P, Dalvie D, Smith E, Zhou S, Deese A. Identification of a novel glutathione conjugate of flutamide in incubations with human liver microsomes. Drug Metab Dispos 2007; 35:1081-8. [PMID: 17403914 DOI: 10.1124/dmd.107.014860] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Flutamide, a nonsteroidal antiandrogen drug widely used in the treatment of prostate cancer, has been associated with rare incidences of hepatotoxicity in patients. It is believed that bioactivation of flutamide and subsequent covalent binding to cellular proteins is responsible for its toxicity. Current in vitro studies were undertaken to probe the cytochrome P450 (P450)-mediated bioactivation of flutamide and identify the possible reactive species using reduced glutathione (GSH) as a trapping agent. NADPH- and GSH-supplemented human liver microsomal incubations of flutamide gave rise to a novel GSH conjugate where GSH moiety was conjugated to the flutamide molecule via the amide nitrogen, resulting in a sulfenamide. The structure of the conjugate was characterized by liquid chromatography-tandem mass spectrometry and NMR experiments. The conjugate formation was primarily catalyzed by heterologously expressed CYP2C19, CYP1A2, and, to a lesser extent, CYP3A4 and CYP3A5. The mechanism for the formation of this conjugate is unknown; however, a tentative bioactivation mechanism involving a P450-catalyzed abstraction of hydrogen atom from the amide nitrogen of flutamide and the subsequent trapping of the nitrogen-centered radical by GSH or oxidized glutathione (GSSG) was proposed. Interestingly, the same adduct was formed when flutamide was incubated with human liver microsomes in the presence of GSSG and NADPH. This finding suggests that P450-mediated oxidation of flutamide via a nitrogen-centered free radical could be one of the several bioactivation pathways of flutamide. Even though the relationship of the GSH conjugate to flutamide-induced toxicity is unknown, the results have revealed the formation of a novel, hitherto unknown, GSH adduct of flutamide.
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Affiliation(s)
- Ping Kang
- Pharmacokinetics Dynamics and Metabolism, Pfizer Global Research and Development, San Diego, CA 92121, USA.
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Zhao SJ, Chen XJ, Feng YJ. [Influence of long-term treatment with MPA on the biological character of endometrial carcinoma Ishikawa cell]. Fen Zi Xi Bao Sheng Wu Xue Bao 2007; 40:103-12. [PMID: 17580663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The study was undertaken to investigate the effect of long-term treatment with MPA on the growth and invasiveness of endometrial carcinoma Ishikawa cells and the expression of the subtype of estrogen receptor and progesterone receptor. The human endometrial carcinoma Ishikawa cells were continually exposed to 2.5 micromol/L step-wise increase of MPA. MTT assay, flow cytometry and Matrigel invasion assay were used to detect the effect of MPA on the growth, cell cycle distribution and the invasion capability of the cells respectively. RT-PCR was performed to detect the changes of CyclinD1, MMP2 and MMP9 over different time treatment of MPA. Immunocytochemistry was used to examine the expression of estrogen receptor subtype and progesterone receptor subtype. Endometrial carcinoma Ishikawa cells became resistant to the inhibitory effect of MPA over ten months MPA treatment. The cells resistant to the growth inhibitory effect were named progestin-resistant Ishikawa cells and the cells which the progestin-resistant originated from were named the parent Ishikawa cells. The effects of MPA shifted from growth and invasiveness inhibitory effects on the parent Ishikawa cells to stimulatory effect on the progestin-resistant Ishikawa cells. Consistent with the phenomena, the treatment with MPA on Ishikawa cells resulted in statistically significant decreases of CyclinD1, MMP2 and MMP9 gene expression, reversely, the treatment with MPA on the progestin-resistant Ishikawa cell resulted in statistically significant increases of CyclinD1, MMP2, MMP9 gene expression. Immunocytochemical analysis showed reduced ERalpha and PR-B expression and increased ERbeta expression in the progestin-resistant Ishikawa cells compared with parental Ishikawa cells. From the experiment, it was concluded that the prolonged treatment with MPA on Ishikawa cell could give rise of the resistant effect of MPA, the effect of MPA on the growth and invasiveness capability of endometrial carcinoma shifted from inhibitory to stimulatory. The imbalance of ER subtype and PR subtype might contribute to the mechanisms involved in the progesterone resistance over long-term MPA treatment.
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Affiliation(s)
- Shu Jun Zhao
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai 200011
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Chu I, Sun J, Arnaout A, Kahn H, Hanna W, Narod S, Sun P, Tan CK, Hengst L, Slingerland J. p27 phosphorylation by Src regulates inhibition of cyclin E-Cdk2. Cell 2007; 128:281-94. [PMID: 17254967 PMCID: PMC1961623 DOI: 10.1016/j.cell.2006.11.049] [Citation(s) in RCA: 284] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Revised: 10/03/2006] [Accepted: 11/20/2006] [Indexed: 01/02/2023]
Abstract
The kinase inhibitor p27Kip1 regulates the G1 cell cycle phase. Here, we present data indicating that the oncogenic kinase Src regulates p27 stability through phosphorylation of p27 at tyrosine 74 and tyrosine 88. Src inhibitors increase cellular p27 stability, and Src overexpression accelerates p27 proteolysis. Src-phosphorylated p27 is shown to inhibit cyclin E-Cdk2 poorly in vitro, and Src transfection reduces p27-cyclin E-Cdk2 complexes. Our data indicate that phosphorylation by Src impairs the Cdk2 inhibitory action of p27 and reduces its steady-state binding to cyclin E-Cdk2 to facilitate cyclin E-Cdk2-dependent p27 proteolysis. Furthermore, we find that Src-activated breast cancer lines show reduced p27 and observe a correlation between Src activation and reduced nuclear p27 in 482 primary human breast cancers. Importantly, we report that in tamoxifen-resistant breast cancer cell lines, Src inhibition can increase p27 levels and restore tamoxifen sensitivity. These data provide a new rationale for Src inhibitors in cancer therapy.
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Affiliation(s)
- Isabel Chu
- Braman Family Breast Cancer Institute, and Department of Biochemistry and Molecular Biology, U. of Miami Miller School of Medicine, Miami, Florida; U.S.A
- Departments of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Jun Sun
- Braman Family Breast Cancer Institute, and Department of Biochemistry and Molecular Biology, U. of Miami Miller School of Medicine, Miami, Florida; U.S.A
| | - Angel Arnaout
- Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Harriette Kahn
- Pathobiology and Lab Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Wedad Hanna
- Pathobiology and Lab Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Steven Narod
- Pathobiology and Lab Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Ping Sun
- Pathobiology and Lab Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Cheng-Keat Tan
- Braman Family Breast Cancer Institute, and Department of Biochemistry and Molecular Biology, U. of Miami Miller School of Medicine, Miami, Florida; U.S.A
| | - Ludger Hengst
- Division of Medical Biochemistry, Biocenter - Innsbruck Medical University, Innsbruck, Austria
| | - Joyce Slingerland
- Braman Family Breast Cancer Institute, and Department of Biochemistry and Molecular Biology, U. of Miami Miller School of Medicine, Miami, Florida; U.S.A
- Departments of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
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Nagaoka R, Iwasaki T, Rokutanda N, Takeshita A, Koibuchi Y, Horiguchi J, Shimokawa N, Iino Y, Morishita Y, Koibuchi N. Tamoxifen activates CYP3A4 and MDR1 genes through steroid and xenobiotic receptor in breast cancer cells. Endocrine 2006; 30:261-8. [PMID: 17526937 DOI: 10.1007/s12020-006-0003-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 10/31/2006] [Accepted: 11/27/2006] [Indexed: 10/23/2022]
Abstract
Cytochrome P450 monooxygenase 3A4 (CYP3A4) and P-glycoprotein, encoded by multidrug resistance 1 (MDR1) gene, are responsible for the metabolism of endogenous steroids, prescribed drugs, and xenobiotics. Both genes are regulated by steroid and xenobiotic receptor (SXR), a member of nuclear hormone receptors. Various endogenous steroids and drugs function as ligands of SXR. Although CYP3A4, MDR1, and SXR are expressed mainly in the liver and the small intestine, these gene products are also expressed in breast cancer cells. Because tamoxifen (TAM) is known to be metabolized by CYP3A4 and P-glycoprotein, we investigated the effect of TAM on these SXR-targeted genes in breast cancer cells. Transient transfection-based reporter gene assays showed 4-hydroxy TAM activated the SXR-mediated transcription through CYP3A4 and MDR1 promoters in a ligand- and receptor concentration-dependent manner. We confirmed the binding of 4-hydroxy TAM to SXR by ligand binding assay. Moreover, semiquantitative RT-PCR studies revealed that 4-hydroxy TAM activated the expression of CYP3A4 and MDR1 mRNA in MCF-7 cells. These results suggest that TAM induces CYP3A4 and MDR1 gene expression through SXR, which may affect TAM metabolic pathway in breast cancer cells.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism
- Adenocarcinoma/metabolism
- Antineoplastic Agents, Hormonal/metabolism
- Breast Neoplasms/metabolism
- Cell Line, Tumor
- Cytochrome P-450 CYP3A
- Cytochrome P-450 Enzyme System/genetics
- Cytochrome P-450 Enzyme System/metabolism
- Dose-Response Relationship, Drug
- Drug Resistance, Neoplasm/physiology
- Estrogen Antagonists/metabolism
- Gene Expression Regulation, Neoplastic
- Genes, MDR
- Humans
- Pregnane X Receptor
- RNA, Messenger/metabolism
- Receptors, Steroid/metabolism
- Receptors, Steroid/physiology
- Retinoid X Receptors/metabolism
- Tamoxifen/analogs & derivatives
- Tamoxifen/metabolism
- Transcription, Genetic
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Affiliation(s)
- Rin Nagaoka
- Department of Integrative Physiology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
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48
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Bonanni B, Macis D, Maisonneuve P, Johansson HA, Gucciardo G, Oliviero P, Travaglini R, Muraca MG, Rotmensz N, Veronesi U, Decensi AU. Polymorphism in the CYP2D6 tamoxifen-metabolizing gene influences clinical effect but not hot flashes: data from the Italian Tamoxifen Trial. J Clin Oncol 2006; 24:3708-9; author reply 3709. [PMID: 16877740 DOI: 10.1200/jco.2006.06.8072] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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Borges S, Desta Z, Li L, Skaar TC, Ward BA, Nguyen A, Jin Y, Storniolo AM, Nikoloff DM, Wu L, Hillman G, Hayes DF, Stearns V, Flockhart DA. Quantitative effect of CYP2D6 genotype and inhibitors on tamoxifen metabolism: implication for optimization of breast cancer treatment. Clin Pharmacol Ther 2006; 80:61-74. [PMID: 16815318 DOI: 10.1016/j.clpt.2006.03.013] [Citation(s) in RCA: 352] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2005] [Accepted: 03/28/2006] [Indexed: 11/19/2022]
Abstract
BACKGROUND AND OBJECTIVES N-Desmethyltamoxifen (NDM), a major primary metabolite of tamoxifen, is hydroxylated by cytochrome P450 (CYP) 2D6 to yield endoxifen. Because of its high antiestrogenic potency, endoxifen may play an important role in the clinical activity of tamoxifen. We conducted a prospective trial in 158 patients with breast cancer who were taking tamoxifen to further understand the effect of CYP2D6 genotype and concomitant medications on endoxifen plasma concentrations. METHODS Medication history, genotype for 33 CYP2D6 alleles, and plasma concentrations of tamoxifen and its metabolites were determined at the fourth month of tamoxifen treatment. RESULTS By use of a mixture model approach, endoxifen plasma concentration identified 2 phenotypic groups, whereas 4 were defined by the endoxifen/NDM plasma concentration ratio. Three distinct genotype groups were identified in the distribution of endoxifen/NDM ratio: (1) low ratios composed of patients lacking any functional allele (mean, 0.04 +/- 0.02); (2) intermediate ratios represented by patients with 1 active allele (mean, 0.08 +/- 0.04); and (3) high ratios composed of patients with 2 or more functional alleles (mean, 0.15 +/- 0.09). Endoxifen/NDM plasma ratios were significantly different between these groups (P < .001). The mean endoxifen plasma concentration was significantly lower in CYP2D6 extensive metabolizers who were taking potent CYP2D6 inhibitors than in those who were not taking CYP2D6 inhibitors (23.5 +/- 9.5 nmol/L versus 84.1 +/- 39.4 nmol/L, P < .001). CONCLUSION CYP2D6 genotype and concomitant potent CYP2D6 inhibitors are highly associated with endoxifen plasma concentration and may have an impact on the response to tamoxifen therapy. These iterative approaches may be valuable in the study of other complex genotype-phenotype relationships.
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Affiliation(s)
- Silvana Borges
- Department of Medicine, Division of Clinical Pharmacology, Indiana University School of Medicine, Indianapolis, 46202, USA.
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Tryndyak VP, Muskhelishvili L, Kovalchuk O, Rodriguez-Juarez R, Montgomery B, Churchwell MI, Ross SA, Beland FA, Pogribny IP. Effect of long-term tamoxifen exposure on genotoxic and epigenetic changes in rat liver: implications for tamoxifen-induced hepatocarcinogenesis. Carcinogenesis 2006; 27:1713-20. [PMID: 16632870 DOI: 10.1093/carcin/bgl050] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tamoxifen is a non-steroidal anti-estrogen used for the treatment of breast cancer and, more recently, as a chemopreventive agent in healthy women at high risk of developing breast cancer. On the other hand, tamoxifen is a potent hepatocarcinogen in rats, with both tumor-initiating and tumor-promoting properties. There is substantial evidence that hepatic tumors in rats are initiated as a result of formation of tamoxifen-DNA adducts; however, events subsequent to DNA adduct formation are not clear. Recently, it has been demonstrated that genotoxic carcinogens, in addition to exerting genotoxic effects, often cause epigenetic alterations. In the current study, we investigated whether or not the mechanism of tamoxifen-induced hepatocarcinogenesis includes both genotoxic and epigenetic components. Female Fisher 344 rats were fed a 420 p.p.m. tamoxifen diet for 6, 12, 18 or 24 weeks. Hepatic tamoxifen-DNA adduct levels, as assessed by high-performance liquid chromatography and electrospray tandem mass spectrometry, were 580 adducts/10(8) nt at 6 weeks, and increased to approximately 1700 adducts/10(8) nt by 18 weeks. Global liver DNA hypomethylation, as determined by an HpaII-based cytosine extension assay, was increased at all time points, with the maximum increase (approximately 200%) occurring at 6 weeks. Protein expressions of maintenance (DNMT1) DNA methyltransferase and de novo DNA methyltransferases DNMT3a and DNMT3b were decreased at all time points. Likewise, trimethylation of histone H4 lysine 20 was significantly decreased at all time points. In contrast, non-target tissues (i.e. mammary gland, pancreas and spleen) did not show any changes in global DNA methylation or DNA methyltransferase activity. These data indicate the importance of genotoxic and epigenetic alterations in the etiology of tamoxifen-induced hepatocarcinogenesis.
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Affiliation(s)
- Volodymyr P Tryndyak
- Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, AR 72079, USA
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