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Agema BC, Buijs SM, Sassen SDT, Mürdter TE, Schwab M, Koch BCP, Jager A, van Schaik RHN, Mathijssen RHJ, Koolen SLW. Toward model-informed precision dosing for tamoxifen: A population-pharmacokinetic model with a continuous CYP2D6 activity scale. Biomed Pharmacother 2023; 160:114369. [PMID: 36753957 DOI: 10.1016/j.biopha.2023.114369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
BACKGROUND Tamoxifen is important in the adjuvant treatment of breast cancer. A plasma concentration of the active metabolite endoxifen of > 16 nM is associated with a lower risk of breast cancer-recurrence. Since inter-individual variability is high and > 20 % of patients do not reach endoxifen levels > 16 nM with the standard dose tamoxifen, therapeutic drug monitoring is advised. However, ideally, the correct tamoxifen dose should be known prior to start of therapy. Our aim is to develop a population pharmacokinetic (POP-PK) model incorporating a continuous CYP2D6 activity scale to support model informed precision dosing (MIPD) of tamoxifen to determine the optimal tamoxifen starting dose. METHODS Data from eight different clinical studies were pooled (539 patients, 3661 samples) and used to develop a POP-PK model. In this model, CYP2D6 activity per allele was estimated on a continuous scale. After inclusion of covariates, the model was subsequently validated using an independent external dataset (378 patients). Thereafter, dosing cut-off values for MIPD were determined. RESULTS A joint tamoxifen/endoxifen POP-PK model was developed describing the endoxifen formation rate. Using a continuous CYP2D6 activity scale, variability in predicting endoxifen levels was decreased by 37 % compared to using standard CYP2D6 genotype predicted phenotyping. After external validation and determination of dosing cut-off points, MIPD could reduce the proportion of patients with subtherapeutic endoxifen levels at from 22.1 % toward 4.8 %. CONCLUSION Implementing MIPD from the start of tamoxifen treatment with this POP-PK model can reduce the proportion of patients with subtherapeutic endoxifen levels at steady-state to less than 5 %.
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Affiliation(s)
- Bram C Agema
- Dept. of Medical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center; Rotterdam, the Netherlands; Dept. of Clinical Pharmacy, Erasmus University Medical Center; Rotterdam, the Netherlands.
| | - Sanne M Buijs
- Dept. of Medical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center; Rotterdam, the Netherlands
| | - Sebastiaan D T Sassen
- Dept. of Clinical Pharmacy, Erasmus University Medical Center; Rotterdam, the Netherlands; Rotterdam Clinical Pharmacometrics Group; Rotterdam, the Netherlands
| | - Thomas E Mürdter
- Margarete Fischer-Bosch-Institute of Clinical Pharmacology; Stuttgart, Germany; University of Tübingen; Tübingen, Germany
| | - Mathias Schwab
- Margarete Fischer-Bosch-Institute of Clinical Pharmacology; Stuttgart, Germany; Dept. of Clinical Pharmacology, University Hospital Tübingen; Tübingen, Germany; iFIT Cluster of Excellence (EXC2180) "Image Guided and Functionally Instructed Tumor Therapies", University of Tübingen, Tübingen, Germany
| | - Birgit C P Koch
- Dept. of Clinical Pharmacy, Erasmus University Medical Center; Rotterdam, the Netherlands; Rotterdam Clinical Pharmacometrics Group; Rotterdam, the Netherlands
| | - Agnes Jager
- Dept. of Medical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center; Rotterdam, the Netherlands
| | - Ron H N van Schaik
- Dept. of Clinical Chemistry, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Ron H J Mathijssen
- Dept. of Medical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center; Rotterdam, the Netherlands
| | - Stijn L W Koolen
- Dept. of Medical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center; Rotterdam, the Netherlands; Dept. of Clinical Pharmacy, Erasmus University Medical Center; Rotterdam, the Netherlands
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2
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Koubek EJ, Ralya AT, Larson TR, McGovern RM, Buhrow SA, Covey JM, Adjei AA, Takebe N, Ames MM, Goetz MP, Reid JM. Population Pharmacokinetics of Z-Endoxifen in Patients With Advanced Solid Tumors. J Clin Pharmacol 2022; 62:1121-1131. [PMID: 35358345 PMCID: PMC9339467 DOI: 10.1002/jcph.2053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 03/24/2022] [Indexed: 11/11/2022]
Abstract
The purpose of this study was to develop and validate a population pharmacokinetic model for Z-endoxifen in patients with advanced solid tumors and to identify clinical variables that influence pharmacokinetic parameters. Z-endoxifen-HCl was administered orally once a day on a 28-day cycle (±3 days) over 11 dose levels ranging from 20 to 360 mg. A total of 1256 Z-endoxifen plasma concentration samples from 80 patients were analyzed using nonlinear mixed-effects modeling to develop a population pharmacokinetic model for Z-endoxifen. A 2-compartment model with oral depot and linear elimination adequately described the data. The estimated apparent total clearance, apparent central volume of distribution, and apparent peripheral volume of distribution were 4.89 L/h, 323 L, and 39.7 L, respectively, with weight-effect exponents of 0.75, 1, and 1, respectively. This model was used to explore the effects of clinical and demographic variables on Z-endoxifen pharmacokinetics. Weight, race on clearance, and aspartate aminotransferase on the absorption rate constant were identified as significant covariates in the final model. This novel population pharmacokinetic model provides insight regarding factors that may affect the pharmacokinetics of Z-endoxifen and may assist in the design of future clinical trials.
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Affiliation(s)
- Emily J. Koubek
- Department of Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Thomas R. Larson
- Department of Oncology, Mayo Clinic, Rochester, Minnesota, USA
- Molecular Pharmacology and Experimental Therapeutics Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, USA
| | | | - Sarah A. Buhrow
- Department of Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Alex A. Adjei
- Department of Oncology, Mayo Clinic, Rochester, Minnesota, USA
- Department of Pharmacology, Mayo Clinic, Rochester, Minnesota, USA
| | - Naoko Takebe
- National Cancer Institute, Bethesda, Maryland, USA
| | - Matthew M. Ames
- Department of Oncology, Mayo Clinic, Rochester, Minnesota, USA
- Department of Pharmacology, Mayo Clinic, Rochester, Minnesota, USA
| | - Matthew P. Goetz
- Department of Oncology, Mayo Clinic, Rochester, Minnesota, USA
- Department of Pharmacology, Mayo Clinic, Rochester, Minnesota, USA
| | - Joel M. Reid
- Department of Oncology, Mayo Clinic, Rochester, Minnesota, USA
- Department of Pharmacology, Mayo Clinic, Rochester, Minnesota, USA
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3
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Chemical alternative for cell identification and cross-contamination detection. 3 Biotech 2022; 12:78. [PMID: 35251881 PMCID: PMC8881561 DOI: 10.1007/s13205-022-03144-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 02/09/2022] [Indexed: 11/01/2022] Open
Abstract
Misidentification of human cell lines has previously led to confusing results during cell culture experiments. Although several enzymatic as well as molecular analysis approaches have been developed for cell-line authentication, these methods remain costly. In the present paper, we describe a simple chemical alternative based on known compound cell cytotoxicity. In addition to cisplatin, a pool of eight tamoxifen derivative compounds was used to compare the cytotoxic effects on three different breast cancer cell lines: MCF-7, T47D and MDA-MB-231. Our results show that four out of the eight cytotoxic-related compounds allowed to distinguish the different cell lines based on their IC50 (the half maximal inhibitory concentration) values which are cell type dependent. The remaining chemicals, particularly the most cytotoxic P15, showed close IC50 values for all the cell lines. Interestingly, flow cytometry experiments have identified notable differences among the three cell lines treated with P15. T47D and MDA-MB231 cells were blocked in SubG1 phase and S phase, respectively, while no significant change in cell cycle profile was noticed for MCF-7 cells. Differences were also noted at the level of caspase-3 activity and cell proliferation in P15-treated cells.
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4
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Ahmad A, Sheikh S, Khan MA, Chaturvedi A, Patel P, Patel R, Buch BC, Anand RS, Shah TC, Vora VN, Ramasubramanian V, Rao S, Kumar N, Prasad BSV, Sathianathan R, Verma KK, Jhanwar VG, Kumar N, Shah S, Dalal PK, Sindhu B, Talukdar P, Ahmad I. Endoxifen: A new, protein kinase C inhibitor to treat acute and mixed mania associated with bipolar I disorder. Bipolar Disord 2021; 23:595-603. [PMID: 33368969 DOI: 10.1111/bdi.13041] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 10/19/2020] [Accepted: 12/20/2020] [Indexed: 12/28/2022]
Abstract
OBJECTIVES Endoxifen is a protein kinase C inhibitor. The objective of the present phase III study was to demonstrate the safety and efficacy of endoxifen in treating bipolar I disorder (BPD I) patients. METHODS A multicenter, double-blind, active-controlled study was conducted using a daily dose of 8 mg endoxifen compared to 1000 mg divalproex, the current standard treatment, in patients with BPD I acute manic episodes with/without mixed features. The primary endpoint of our study was the mean change in total Young Mania Rating Scale (YMRS) score at day 21. RESULTS Endoxifen (n = 116) significantly (p < 0.0001) reduced total YMRS score (from 33.1 to 17.8. A significant (p < 0.001) improvement in Montgomery-Åsberg Depression Rating Scale (MADRS) score was observed for endoxifen (4.8 to 2.5). Early time to remission of the disease was observed with endoxifen compared to divalproex. None of the patients required rescue medication and there was no drug-associated withdrawals. Changes in Clinical Global Impressions-Bipolar Disorder and Clinical Global Impression-Severity of Illness scores showed that treatment with endoxifen was well-tolerated. CONCLUSIONS Endoxifen at a low daily dose of 8 mg was as efficacious and safe in patients with BPD I acute manic episodes with/without mixed features.
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Affiliation(s)
- Ateeq Ahmad
- Jina Pharmaceuticals Inc, Libertyville, IL, USA
| | | | | | | | - Piyush Patel
- Intas Pharmaceuticals Ltd, Ahmedabad, Gujarat, India
| | - Ronak Patel
- Lambda Therapeutic Research Ltd, Ahmedabad, Gujarat, India
| | | | | | | | | | | | | | - Narendra Kumar
- Mysore Medical College and Research Institute, K.R. Hospital, Mysore, Karnataka, India
| | - B S V Prasad
- Sujata Birla Hospital and Medical Research Center, Nasik, Maharashtra, India
| | | | | | - Venu Gopal Jhanwar
- Deva Institute of Healthcare and Research, Varanasi, Uttar Pradesh, India
| | - Nand Kumar
- All India Institute of Medical Sciences, New Delhi, India
| | - Sandip Shah
- Gujarat Medical Education & Research Society Medical College, Gotri, Vadodara, India
| | - Pronob Kumar Dalal
- King George's Medical University, G.M. Associated Hospitals, Lucknow, Uttar Pradesh, India
| | | | - Payel Talukdar
- Nil Ratan Sircar Medical College and Hospital, Kolkata, West Bengal, India
| | - Imran Ahmad
- Jina Pharmaceuticals Inc, Libertyville, IL, USA
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Chen KJ, Plaunt AJ, Leifer FG, Kang JY, Cipolla D. Recent advances in prodrug-based nanoparticle therapeutics. Eur J Pharm Biopharm 2021; 165:219-243. [PMID: 33979661 DOI: 10.1016/j.ejpb.2021.04.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 03/10/2021] [Accepted: 04/26/2021] [Indexed: 12/17/2022]
Abstract
Extensive research into prodrug modification of active pharmaceutical ingredients and nanoparticle drug delivery systems has led to unprecedented levels of control over the pharmacological properties of drugs and resulted in the approval of many prodrug or nanoparticle-based therapies. In recent years, the combination of these two strategies into prodrug-based nanoparticle drug delivery systems (PNDDS) has been explored as a way to further advance nanomedicine and identify novel therapies for difficult-to-treat indications. Many of the PNDDS currently in the clinical development pipeline are expected to enter the market in the coming years, making the rapidly evolving field of PNDDS highly relevant to pharmaceutical scientists. This review paper is intended to introduce PNDDS to the novice reader while also updating those working in the field with a comprehensive summary of recent efforts. To that end, first, an overview of FDA-approved prodrugs is provided to familiarize the reader with their advantages over traditional small molecule drugs and to describe the chemistries that can be used to create them. Because this article is part of a themed issue on nanoparticles, only a brief introduction to nanoparticle-based drug delivery systems is provided summarizing their successful application and unfulfilled opportunities. Finally, the review's centerpiece is a detailed discussion of rationally designed PNDDS formulations in development that successfully leverage the strengths of prodrug and nanoparticle approaches to yield highly effective therapeutic options for the treatment of many diseases.
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6
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Blum KM, Roby LC, Zbinden JC, Chang YC, Mirhaidari GJM, Reinhardt JW, Yi T, Barker JC, Breuer CK. Sex and Tamoxifen confound murine experimental studies in cardiovascular tissue engineering. Sci Rep 2021; 11:8037. [PMID: 33850181 PMCID: PMC8044102 DOI: 10.1038/s41598-021-87006-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 02/25/2021] [Indexed: 02/01/2023] Open
Abstract
Tissue engineered vascular grafts hold promise for the creation of functional blood vessels from biodegradable scaffolds. Because the precise mechanisms regulating this process are still under investigation, inducible genetic mouse models are an important and widely used research tool. However, here we describe the importance of challenging the baseline assumption that tamoxifen is inert when used as a small molecule inducer in the context of cardiovascular tissue engineering. Employing a standard inferior vena cava vascular interposition graft model in C57BL/6 mice, we discovered differences in the immunologic response between control and tamoxifen-treated animals, including occlusion rate, macrophage infiltration and phenotype, the extent of foreign body giant cell development, and collagen deposition. Further, differences were noted between untreated males and females. Our findings demonstrate that the host-response to materials commonly used in cardiovascular tissue engineering is sex-specific and critically impacted by exposure to tamoxifen, necessitating careful model selection and interpretation of results.
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Affiliation(s)
- Kevin M Blum
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, USA
| | - Lauren C Roby
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
- College of Medicine, The Ohio State University, Columbus, USA
| | - Jacob C Zbinden
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, USA
| | - Yu-Chun Chang
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
- Biomedical Sciences Graduate Program, College of Medicine, The Ohio State University, Columbus, USA
| | - Gabriel J M Mirhaidari
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
- Biomedical Sciences Graduate Program, College of Medicine, The Ohio State University, Columbus, USA
| | - James W Reinhardt
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
| | - Tai Yi
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
| | - Jenny C Barker
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA
- Department of Plastic and Reconstructive Surgery, The Ohio State University, Columbus, USA
| | - Christopher K Breuer
- Center for Regenerative Medicine, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, USA.
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7
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DeLarge AF, Winsauer PJ. Effects of ∆ 9-THC on memory in ovariectomized and intact female rats. Horm Behav 2021; 127:104883. [PMID: 33160960 PMCID: PMC7856115 DOI: 10.1016/j.yhbeh.2020.104883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 12/01/2022]
Abstract
The effects of marijuana's major psychoactive cannabinoid, ∆9-tetrahydrocannibinol (∆9-THC), were examined on memory in female rats by training subjects to respond under a repeated acquisition and delayed-performance procedure. During this task, subjects acquired a different 4-response sequence each session, which was then recalled after a delay. Sequence retention was tested following various delays, and quantified by a percent savings measure. Response rate and percent errors were also recorded. Subsequent to training, subjects underwent an ovariectomy (OVX) or sham surgery (intact). The OVX group then underwent implantation of subcutaneous 17β-estradiol capsules while the intact group received chronic administration of 1 mg/kg of the estrogen receptor modifier, tamoxifen. Increasing delays from 1 min to 24 h produced delay-dependent decreases in percent savings in both OVX and intact rats. Acute administration of ∆9-THC (0.32-3.2 mg/kg) dose-dependently decreased retention, increased percent errors, and decreased response rate in both groups when the delay was 1 h. However, intact rats showed a significantly lower percent savings than OVX rats at the 0.56-mg/kg dose. Delays of 3 h enhanced the disruptive effects of ∆9-THC more in intact than OVX rats; furthermore, implantation of 17β-estradiol attenuated ∆9-THC-induced disruptions in OVX rats and significantly increased estradiol levels and uterine weight as compared to intact rats. Although chronic tamoxifen administration did not alter ∆9-THC's effects on memory in intact rats, it did significantly decrease response rate. These results demonstrate the capacity of chronic 17β-estradiol for attenuating ∆9-THC's acute memory-disrupting effects in OVX female rats.
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Affiliation(s)
- Alyssa F DeLarge
- Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center - New Orleans, United States of America.
| | - Peter J Winsauer
- Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center - New Orleans, United States of America; Alcohol and Drug Abuse Center of Excellence, Louisiana State University Health Sciences Center - New Orleans (P.J.W.), United States of America
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8
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Mueller-Schoell A, Klopp-Schulze L, Schroth W, Mürdter T, Michelet R, Brauch H, Huisinga W, Joerger M, Neven P, Koolen SLW, Mathijssen RHJ, Copson E, Eccles D, Chen S, Chowbay B, Tfayli A, Zgheib NK, Schwab M, Kloft C. Obesity Alters Endoxifen Plasma Levels in Young Breast Cancer Patients: A Pharmacometric Simulation Approach. Clin Pharmacol Ther 2020; 108:661-670. [PMID: 32578187 DOI: 10.1002/cpt.1960] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 05/29/2020] [Indexed: 01/03/2023]
Abstract
Endoxifen is one of the most important metabolites of the prodrug tamoxifen. High interindividual variability in endoxifen steady-state concentrations (CSS,min ENDX ) is observed under tamoxifen standard dosing and patients with breast cancer who do not reach endoxifen concentrations above a proposed therapeutic threshold of 5.97 ng/mL may be at a 26% higher recurrence risk compared with patients with endoxifen concentrations exceeding this value. In this investigation, 10 clinical tamoxifen studies were pooled (1,388 patients) to investigate influential factors on CSS,min ENDX using nonlinear mixed-effects modeling. Age and body weight were found to significantly impact CSS,min ENDX in addition to CYP2D6 phenotype. Compared with postmenopausal patients, premenopausal patients had a 30% higher risk for subtarget CSS,min ENDX at tamoxifen 20 mg per day. In treatment simulations for distinct patient subpopulations, young overweight patients had a 3.1-13.8-fold higher risk for subtarget CSS,min ENDX compared with elderly low-weight patients. Considering ever-rising obesity rates and the clinical importance of tamoxifen for premenopausal patients, this subpopulation may benefit most from individualized tamoxifen dosing.
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Affiliation(s)
- Anna Mueller-Schoell
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Freie Universitaet Berlin, Berlin, Germany
- Graduate Research Training Program PharMetrX, Berlin/Potsdam, Germany
| | - Lena Klopp-Schulze
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Freie Universitaet Berlin, Berlin, Germany
| | - Werner Schroth
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - Thomas Mürdter
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - Robin Michelet
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Freie Universitaet Berlin, Berlin, Germany
| | - Hiltrud Brauch
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
- German Cancer Consortium (DKTK) and of German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Wilhelm Huisinga
- Institute of Mathematics, University of Potsdam, Potsdam, Germany
| | - Markus Joerger
- Department of Medical Oncology and Haematology, Cantonal Hospital, St. Gallen, Switzerland
| | - Patrick Neven
- Vesalius Research Center - VIB, University Hospitals Leuven, KU Leuven-University of Leuven, Leuven, Belgium
| | - Stijn L W Koolen
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ron H J Mathijssen
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ellen Copson
- Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton, Southampton, UK
- University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Diana Eccles
- Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton, Southampton, UK
- University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Sylvia Chen
- Clinical Pharmacology Laboratory, Division of Cellular & Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore
| | - Balram Chowbay
- Clinical Pharmacology Laboratory, Division of Cellular & Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore
- Center for Clinician-Scientist Development, Duke-NUS Medical School, Singapore
- SingHealth Clinical Pharmacology, SingHealth, Singapore
| | - Arafat Tfayli
- Hematology-Oncology Division, Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Nathalie K Zgheib
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
- German Cancer Consortium (DKTK) and of German Cancer Research Center (DKFZ), Heidelberg, Germany
- Departments of Clinical Pharmacology, Pharmacy and Biochemistry, University Tübingen, Tübingen, Germany
| | - Charlotte Kloft
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Freie Universitaet Berlin, Berlin, Germany
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Oceguera-Basurto P, Topete A, Oceguera-Villanueva A, Rivas-Carrillo J, Paz-Davalos M, Quintero-Ramos A, Del Toro-Arreola A, Daneri-Navarro A. Selective estrogen receptor modulators in the prevention of breast cancer in premenopausal women: a review. Transl Cancer Res 2020; 9:4444-4456. [PMID: 35117809 PMCID: PMC8797886 DOI: 10.21037/tcr-19-1956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 06/15/2020] [Indexed: 12/28/2022]
Abstract
The detection of premenopausal women at high risk of breast cancer is key to chemoprevention. Therapy with selective estrogen receptor modulators (SERMs) induces a significant antiproliferative effect in estrogen receptor (ER) positive breast cancer. This review was designed according the guidelines of the 2009 PRISMA statement. Searching different databases, including PubMed, MedlinePlus, PLoS One, Cochrane Breast Cancer Specialized Register, Clinical Trials.gov and American Society of Clinical Oncology. From 168 records screened, 15 full text articles were assessed for eligibility and only 7 studies met the inclusion criteria. Three of the studies included analyzed changes in Ki-67 expression, revealing weaker expression after treatment with acolbifene and raloxifene (P<0.001). Three studies also analyzed the breast volume by magnetic resonance imagining (MRI) and demonstrate a significant difference after 1 year with raloxifene treatment (P=0.0017). Moreover, a 20% reduction in breast density was observed after a 2-year treatment with tamoxifen in premenopausal women. SERMs reduce the risk of developing breast cancer. The studies reviewed here demonstrate the modulation of Ki-67 expression and changes in breast density, suggesting an important preventive role for this group of drugs in prevention for premenopausal women at high risk of developing breast cancer.
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Affiliation(s)
- Paola Oceguera-Basurto
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, México
| | - Antonio Topete
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, México
| | | | - Jorge Rivas-Carrillo
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, México
| | | | - Antonio Quintero-Ramos
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, México
| | - Alicia Del Toro-Arreola
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, México
| | - Adrián Daneri-Navarro
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, México
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10
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Klopp-Schulze L, Mueller-Schoell A, Neven P, Koolen SLW, Mathijssen RHJ, Joerger M, Kloft C. Integrated Data Analysis of Six Clinical Studies Points Toward Model-Informed Precision Dosing of Tamoxifen. Front Pharmacol 2020; 11:283. [PMID: 32296331 PMCID: PMC7136483 DOI: 10.3389/fphar.2020.00283] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/27/2020] [Indexed: 12/16/2022] Open
Abstract
Introduction At tamoxifen standard dosing, ∼20% of breast cancer patients do not reach proposed target endoxifen concentrations >5.97 ng/mL. Thus, better understanding the large interindividual variability in tamoxifen pharmacokinetics (PK) is crucial. By applying non-linear mixed-effects (NLME) modeling to a pooled ‘real-world’ clinical PK database, we aimed to (i) dissect several levels of variability and identify factors predictive for endoxifen exposure and (ii) assess different tamoxifen dosing strategies for their potential to increase the number of patients reaching target endoxifen concentrations. Methods Tamoxifen and endoxifen concentrations with genetic and demographic data of 468 breast cancer patients from six reported studies were used to develop a NLME parent-metabolite PK model. Different levels of variability on model parameters or measurements were investigated and the impact of covariates thereupon explored. The model was subsequently applied in a simulation-based comparison of three dosing strategies with increasing degree of dose individualization for a large virtual breast cancer population. Interindividual variability of endoxifen concentrations and the fraction of patients at risk for not reaching target concentrations were assessed for each dosing strategy. Results and Conclusions The integrated NLME model enabled to differentiate and quantify four levels of variability (interstudy, interindividual, interoccasion, and intraindividual). Strong influential factors, i.e., CYP2D6 activity score, drug–drug interactions with CYP3A and CYP2D6 inducers/inhibitors and age, were reliably identified, reducing interoccasion variability to <20% CV. Yet, unexplained interindividual variability in endoxifen formation remained large (47.2% CV). Hence, therapeutic drug monitoring seems promising for achieving endoxifen target concentrations. Three tamoxifen dosing strategies [standard dosing (20 mg QD), CYP2D6-guided dosing (20, 40, and 60 mg QD) and individual model-informed precision dosing (MIPD)] using three therapeutic drug monitoring samples (5–120 mg QD) were compared, leveraging the model. The proportion of patients at risk for not reaching target concentrations was 22.2% in standard dosing, 16.0% in CYP2D6-guided dosing and 7.19% in MIPD. While in CYP2D6-guided- and standard dosing interindividual variability in endoxifen concentrations was high (64.0% CV and 68.1% CV, respectively), it was considerably reduced in MIPD (24.0% CV). Hence, MIPD demonstrated to be the most promising strategy for achieving target endoxifen concentrations.
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Affiliation(s)
- Lena Klopp-Schulze
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Free University of Berlin, Berlin, Germany
| | - Anna Mueller-Schoell
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Free University of Berlin, Berlin, Germany.,Graduate Research Training Program PharMetrX, Berlin, Germany
| | - Patrick Neven
- Vesalius Research Center, University Hospitals Leuven, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Stijn L W Koolen
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, Netherlands
| | - Ron H J Mathijssen
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, Netherlands
| | - Markus Joerger
- Department of Medical Oncology and Hematology, Cantonal Hospital, St., Gallen, Switzerland
| | - Charlotte Kloft
- Department of Clinical Pharmacy and Biochemistry, Institute of Pharmacy, Free University of Berlin, Berlin, Germany
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11
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Wu K, Pudasaini B, Park JY, Top S, Jaouen G, Baik MH, Geiger WE. Oxidation of Cymantrene-Tagged Tamoxifen Analogues: Effect of Diphenyl Functionalization on the Redox Mechanism. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00822] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kan Wu
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405, United States
| | - Bimal Pudasaini
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, South Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea
| | - Ji Young Park
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, South Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea
| | - Siden Top
- Sorbonne Université, UPMC, CNRS, Institut Parisien de Chimie Moléculaire (IPCM), UMR 8232, 4 Place Jussieu, 75005 Paris, France
| | - Gérard Jaouen
- Sorbonne Université, UPMC, CNRS, Institut Parisien de Chimie Moléculaire (IPCM), UMR 8232, 4 Place Jussieu, 75005 Paris, France
- PSL, Chimie ParisTech, 11 rue Pierre and Marie Curie, F-75005 Paris, France
| | - Mu-Hyun Baik
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, South Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea
| | - William E. Geiger
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405, United States
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12
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Arao Y, Korach KS. Transactivation Function-1-Mediated Partial Agonist Activity of Selective Estrogen Receptor Modulator Requires Homo-Dimerization of the Estrogen Receptor α Ligand Binding Domain. Int J Mol Sci 2019; 20:ijms20153718. [PMID: 31366023 PMCID: PMC6695978 DOI: 10.3390/ijms20153718] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/24/2019] [Accepted: 07/26/2019] [Indexed: 11/16/2022] Open
Abstract
The isolation of estrogen receptor alpha (ERα) cDNA was successful around 30 years ago. The characteristics of ERα protein have been examined from various aspects, primarily through in vitro cell culture studies, but more recently using in vivo experimental models. There remains, however, some uncharacterized ERα functionalities. In particular, the mechanism of partial agonist activity of selective estrogen receptor modulators (SERMs) that involves control of the N-terminal transcription function of ERα, termed AF-1, is still an unsolved ERα functionality. We review the possible mechanism of SERM-dependent regulation of ERα AF-1-mediated transcriptional activity, which includes the role of helix 12 of ERα ligand binding domain (LBD) for SERM-dependent AF-1 regulation. In addition, we describe a specific portion of the LBD that associates with blocking AF-1 activity with an additional role of the F-domain in mediating SERM activity.
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Affiliation(s)
- Yukitomo Arao
- Receptor Biology Section, Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences/NIH, Durham, NC 27709, USA.
| | - Kenneth S Korach
- Receptor Biology Section, Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences/NIH, Durham, NC 27709, USA.
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13
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Baez-Jurado E, Rincón-Benavides MA, Hidalgo-Lanussa O, Guio-Vega G, Ashraf GM, Sahebkar A, Echeverria V, Garcia-Segura LM, Barreto GE. Molecular mechanisms involved in the protective actions of Selective Estrogen Receptor Modulators in brain cells. Front Neuroendocrinol 2019; 52:44-64. [PMID: 30223003 DOI: 10.1016/j.yfrne.2018.09.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/09/2018] [Accepted: 09/12/2018] [Indexed: 02/06/2023]
Abstract
Synthetic selective modulators of the estrogen receptors (SERMs) have shown to protect neurons and glial cells against toxic insults. Among the most relevant beneficial effects attributed to these compounds are the regulation of inflammation, attenuation of astrogliosis and microglial activation, prevention of excitotoxicity and as a consequence the reduction of neuronal cell death. Under pathological conditions, the mechanism of action of the SERMs involves the activation of estrogen receptors (ERs) and G protein-coupled receptor for estrogens (GRP30). These receptors trigger neuroprotective responses such as increasing the expression of antioxidants and the activation of kinase-mediated survival signaling pathways. Despite the advances in the knowledge of the pathways activated by the SERMs, their mechanism of action is still not entirely clear, and there are several controversies. In this review, we focused on the molecular pathways activated by SERMs in brain cells, mainly astrocytes, as a response to treatment with raloxifene and tamoxifen.
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Affiliation(s)
- E Baez-Jurado
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - M A Rincón-Benavides
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - O Hidalgo-Lanussa
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - G Guio-Vega
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - G M Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - A Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - V Echeverria
- Universidad San Sebastián, Fac. Cs de la Salud, Lientur 1457, Concepción 4080871, Chile; Research & Development Service, Bay Pines VA Healthcare System, Bay Pines, FL 33744, USA
| | - L M Garcia-Segura
- Instituto Cajal, CSIC, Madrid, Spain; Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - G E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia; Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile.
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14
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CYP2D6 as a treatment decision aid for ER-positive non-metastatic breast cancer patients: a systematic review with accompanying clinical practice guidelines. Breast Cancer Res Treat 2018; 173:521-532. [PMID: 30411242 DOI: 10.1007/s10549-018-5027-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Accepted: 10/21/2018] [Indexed: 12/11/2022]
Abstract
PURPOSE Tamoxifen is one of the principal treatments for estrogen receptor (ER)-positive breast cancer. Unfortunately, between 30 and 50% of patients receiving this hormonal therapy relapse. Since CYP2D6 genetic variants have been reported to play an important role in survival outcomes after treatment with tamoxifen, this study sought to summarize and critically appraise the available scientific evidence on this topic. METHODS A systematic literature review was conducted to identify studies investigating associations between CYP2D6 genetic variation and survival outcomes after tamoxifen treatment. Critical appraisal of the retrieved scientific evidence was performed, and recommendations were developed for CYP2D6 genetic testing in the context of tamoxifen therapy. RESULTS Although conflicting literature exists, the majority of the current evidence points toward CYP2D6 genetic variation affecting survival outcomes after tamoxifen treatment. Of note, review of the CYP2D6 genotyping assays used in each of the studies revealed the importance of comprehensive genotyping strategies to accurately predict CYP2D6 metabolizer phenotypes. CONCLUSIONS AND RECOMMENDATIONS Critical appraisal of the literature provided evidence for the value of comprehensive CYP2D6 genotyping panels in guiding treatment decisions for non-metastatic ER-positive breast cancer patients. Based on this information, it is recommended that alternatives to standard tamoxifen treatments may be considered in CYP2D6 poor or intermediate metabolizers.
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15
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Xiao X, Li J, Yu T, Zhou L, Fan X, Xiao H, Wang Y, Yang L, Lv J, Jia X, Zhang Z. Bisphenol AP is anti-estrogenic and may cause adverse effects at low doses relevant to human exposure. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:1625-1632. [PMID: 30077407 DOI: 10.1016/j.envpol.2018.07.115] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/07/2018] [Accepted: 07/24/2018] [Indexed: 05/25/2023]
Abstract
A recent increase in the use of bisphenol A (BPA) alternatives to manufacture plastics has led to safety concerns. Here, we evaluated the estrogenic and anti-estrogenic activities of bisphenol AP (BPAP), a poorly studied BPA alternative, using in vitro, in vivo and in silico tools. BPAP exhibited weak estrogenicity but strong anti-estrogenicity (IC50 = 2.35 μM) in a GeneBLAzer™ β-lactamase reporter gene assay. BPAP, when administered alone or in combination with E2 (50 μg kg-1 bw d-1) for 3 d, significantly decreased the uterine weights of post-weaning CD-1 mice at doses of 10 mg kg-1 bw d-1 and higher. When administered alone to prepubertal CD-1 mice for 10 d, BPAP significantly decreased the uterine weights at doses of 80 μg kg-1 bw d-1 and higher. Toxicogenomic analysis showed that BPAP regulated an opposite patterns of gene expression than that of E2 in mouse uteri. In a glucose tolerance test using male mice, BPAP was found to disrupt the blood glucose homeostasis at low doses relevant to human exposure (1 and 100 μg kg-1 bw d-1). Our results suggest that BPAP should be of great concern which might affect the sexual development in immature feminine and disrupt the blood glucose homeostasis at very low doses.
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Affiliation(s)
- Xuan Xiao
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Junyu Li
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Tong Yu
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Lei Zhou
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Xiaolin Fan
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Han Xiao
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Yue Wang
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Lei Yang
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Junhui Lv
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Xiaojing Jia
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China
| | - Zhaobin Zhang
- College of Urban and Environmental Sciences, MOE Laboratory for Earth Surface Process, Peking University, Beijing, 100871, China.
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16
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Liu Z, Cheng Y, Luan Y, Zhong W, Lai H, Wang H, Yu H, Yang Y, Feng N, Yuan F, Huang R, He Z, Zhang F, Yan M, Yin H, Guo F, Zhai Q. Short-term tamoxifen treatment has long-term effects on metabolism in high-fat diet-fed mice with involvement of Nmnat2 in POMC neurons. FEBS Lett 2018; 592:3305-3316. [PMID: 30192985 DOI: 10.1002/1873-3468.13240] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 08/16/2018] [Accepted: 08/25/2018] [Indexed: 01/07/2023]
Abstract
Short-term tamoxifen treatment has effects on lipid and glucose metabolism in mice fed chow. However, its effects on metabolism in mice fed high-fat diet (HFD) and the underlying mechanisms are unclear. Here, we show that tamoxifen treatment for 5 days decreases fat mass for as long as 18 weeks in mice fed HFD. Tamoxifen alters mRNA levels of some genes involved in lipid metabolism in white adipose tissue and improves glucose and insulin tolerance as well as hepatic insulin signaling for 12-20 weeks. Proopiomelanocortin (POMC) neuron-specific deletion of nicotinamide mononucleotide adenylyltransferase 2 (Nmnat2) attenuates the effects of tamoxifen on glucose and insulin tolerance. These data demonstrate that short-term injection of tamoxifen has long-term effects on lipid and glucose metabolism in HFD mice with involvement of Nmnat2 in POMC neurons.
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Affiliation(s)
- Zhiyuan Liu
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Yalan Cheng
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Yi Luan
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Wuling Zhong
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Hejin Lai
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Hui Wang
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Huimin Yu
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Yale Yang
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Ning Feng
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Feixiang Yuan
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Rui Huang
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Zhishui He
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Fang Zhang
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Menghong Yan
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Hao Yin
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Feifan Guo
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Qiwei Zhai
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200031, Shanghai, China.,School of Life Science and Technology, Shanghai Tech University, Shanghai, 200093, China
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Orally administered endoxifen inhibits tumor growth in melanoma-bearing mice. Cell Mol Biol Lett 2018; 23:3. [PMID: 29308069 PMCID: PMC5751858 DOI: 10.1186/s11658-017-0068-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 12/22/2017] [Indexed: 01/10/2023] Open
Abstract
Endoxifen, an active metabolite of tamoxifen, has been shown to be an effective anti-estrogenic agent in estrogen receptor-positive breast cancer patients. In melanoma, estrogen receptor expression is shown to be associated with disease progression. However, the therapeutic benefit of endoxifen in melanoma has not yet been evaluated. Here, we present the first demonstration of the anti-melanogenic activity of endoxifen in vitro and in vivo. The in vitro cytotoxic effect of endoxifen was tested using a cell viability assay. The in vivo anti-melanogenic activity was evaluated in B16F10 cell-bearing C57BL/6 mice, a mouse melanoma model. The general toxicity was tested in Swiss albino mice. Endoxifen exhibited greater activity against melanoma cell lines. Treatment of B16F10 mouse and SK-MEL-5 human melanoma cell lines with 10 μM of endoxifen for 48 h respectively resulted in 93.6 and 92.5% cell death. Orally administered endoxifen, at dose levels of 4 and 8 mg/kg body weight/day for 20 consecutive days, respectively reduced metastatic melanoma nodules in the lungs by 26.7 and 82.7%. Endoxifen was found to be a safe and effective anti-melanogenic agent in animal studies.
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Saxena A, Scaini G, Bavaresco DV, Leite C, Valvassori SS, Carvalho AF, Quevedo J. Role of Protein Kinase C in Bipolar Disorder: A Review of the Current Literature. MOLECULAR NEUROPSYCHIATRY 2017; 3:108-124. [PMID: 29230399 DOI: 10.1159/000480349] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 08/14/2017] [Indexed: 12/19/2022]
Abstract
Bipolar disorder (BD) is a major health problem. It causes significant morbidity and imposes a burden on the society. Available treatments help a substantial proportion of patients but are not beneficial for an estimated 40-50%. Thus, there is a great need to further our understanding the pathophysiology of BD to identify new therapeutic avenues. The preponderance of evidence pointed towards a role of protein kinase C (PKC) in BD. We reviewed the literature pertinent to the role of PKC in BD. We present recent advances from preclinical and clinical studies that further support the role of PKC. Moreover, we discuss the role of PKC on synaptogenesis and neuroplasticity in the context of BD. The recent development of animal models of BD, such as stimulant-treated and paradoxical sleep deprivation, and the ability to intervene pharmacologically provide further insights into the involvement of PKC in BD. In addition, the effect of PKC inhibitors, such as tamoxifen, in the resolution of manic symptoms in patients with BD further points in that direction. Furthermore, a wide variety of growth factors influence neurotransmission through several molecular pathways that involve downstream effects of PKC. Our current understanding identifies the PKC pathway as a potential therapeutic avenue for BD.
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Affiliation(s)
- Ashwini Saxena
- Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Giselli Scaini
- Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Daniela V Bavaresco
- Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, Brazil
| | - Camila Leite
- Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, Brazil
| | - Samira S Valvassori
- Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, Brazil
| | - André F Carvalho
- Translational Psychiatry Research Group, Faculty of Medicine, Federal University of Ceara, Fortaleza, Brazil
| | - João Quevedo
- Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas, USA.,Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciúma, Brazil.,Center of Excellence on Mood Disorders, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas, USA.,Neuroscience Graduate Program, The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas, USA
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Alsharif FM, Dave K, Samy AM, Saleh KI, Amin MA, Perumal O. Influence of Hydroalcoholic Vehicle on In Vitro Transport of 4-Hydroxy Tamoxifen Through the Mammary Papilla (Nipple). AAPS PharmSciTech 2017; 18:1366-1373. [PMID: 27506565 DOI: 10.1208/s12249-016-0608-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 07/28/2016] [Indexed: 01/29/2023] Open
Abstract
Majority of breast cancers originate from epithelial cells in the duct and lobules in the breast. Current systemic treatments for breast cancer are associated with significant systemic side effects, thus warranting localized drug delivery approaches. The aim of this study was to investigate the influence of hydroalcoholic vehicle on topical delivery of 4-hydroxy tamoxifen (4-HT) through the mammary papilla (nipple). The in vitro permeability of 4-HT through porcine mammary papilla was studied using different hydroalcoholic vehicles (0, 33.33, and 66.66% alcohol). Nile red was used as a model lipophilic dye to characterize the drug transport pathway in the mammary papilla. The penetration of 4-HT through the mammary papilla increased with increase in alcohol concentration in the vehicle. The solubility of 4-HT was enhanced by increasing alcohol concentration in the vehicle. On the other hand, the epidermis/vehicle partition coefficient decreased with increase in alcohol concentration. The mammary papilla served as a depot and slowly released 4-HT into the receptor medium. Highest drug penetration was observed with saturated drug solution in 66.66% alcohol, and 4-HT levels were comparable to IC50 value of 4-HT. Results from this study demonstrate the possibility of using mammary papilla as a potential route for direct delivery of 4-HT to the breast.
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20
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Yoosefian M, Etminan N, Ahmadzadeh S. Solvents effect on the stability and reactivity of Tamoxifen and its nano metabolites as the breast anticancer drug. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.09.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Ahmad A, Sheikh S, Shah T, Reddy MS, Prasad B, Verma KK, Chandrakant BB, Paithankar M, Kale P, Solanki RV, Patel R, Barkate H, Ahmad I. Endoxifen, a New Treatment Option for Mania: A Double-Blind, Active-Controlled Trial Demonstrates the Antimanic Efficacy of Endoxifen. Clin Transl Sci 2016; 9:252-259. [PMID: 27346789 PMCID: PMC5350997 DOI: 10.1111/cts.12407] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/24/2016] [Indexed: 11/30/2022] Open
Abstract
The protein kinase C (PKC) signaling system plays a role in mood disorders and PKC inhibitors such as endoxifen may be an innovative medicine for bipolar disorder (BP) patients. In this study we show for the first time the antimanic properties of endoxifen in patients with bipolar I disorder (BPD I) with current manic or mixed episode. In a double-blind, active-controlled study, 84 subjects with BPD I were randomly assigned to receive endoxifen (4 mg/day or 8 mg/day) or divalproex in a 2:1 ratio. Patients orally administered 4 mg/day or 8 mg/day endoxifen showed significant improvement in mania assessed by the Young Mania Rating Scale as early as 4 days. The effect remained significant throughout the 21-day period. At study end point, response rates were 44.44% and 64.29% at 4 mg/day and 8 mg/day of endoxifen treatment, respectively. Thus, endoxifen has been shown as a promising novel antimanic or mood stabilizing agent.
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Affiliation(s)
- A Ahmad
- Jina Pharmaceuticals Inc, Libertyville, Illinois, USA
| | - S Sheikh
- Jina Pharmaceuticals Inc, Libertyville, Illinois, USA
| | - T Shah
- Divyam Hospital, Surat, GJ, India
| | | | - Bsv Prasad
- Sujata Birla Hospital and Medical Research Centre, Nashik, MH, India
| | - K K Verma
- S. P. Medical College & A G Hospitals, Bikaner, RJ, India
| | | | | | - P Kale
- Lambda Therapeutic Research Ltd, Ahmedabad, GJ, India
| | - R V Solanki
- Lambda Therapeutic Research Ltd, Ahmedabad, GJ, India
| | - R Patel
- Lambda Therapeutic Research Ltd, Ahmedabad, GJ, India
| | - H Barkate
- Intas Pharmaceuticals Ltd, Ahmedabad, GJ, India
| | - I Ahmad
- Jina Pharmaceuticals Inc, Libertyville, Illinois, USA
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Borgatta M, Waridel P, Decosterd LA, Buclin T, Chèvre N. Multigenerational effects of the anticancer drug tamoxifen and its metabolite 4-hydroxy-tamoxifen on Daphnia pulex. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 545-546:21-29. [PMID: 26745289 DOI: 10.1016/j.scitotenv.2015.11.155] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Revised: 11/27/2015] [Accepted: 11/27/2015] [Indexed: 06/05/2023]
Abstract
Tamoxifen and its metabolite 4-hydroxy-tamoxifen (4OHTam) are two potent molecules that have anticancer properties on breast cancers. Their medical use is expected to increase with the increasing global cancer rate. After consumption, patients excrete tamoxifen and the 4OHTam metabolite into wastewaters, and tamoxifen has been already detected in wastewaters and natural waters. The concentrations of 4OHTam in waters have never been reported. A single study reported 4OHTam effects on the microcrustacean Daphnia pulex. The effects of tamoxifen and 4OHTam over more than two generations are unknown in aquatic invertebrates. The main goal of this study was to assess the long-term sensitivity of the microcrustacean D. pulex over four generations, based on size, reproduction, viability and the intrinsic rate of natural increase (r). Additional experiments were carried out to observe whether the effects of tamoxifen and 4OHTam were reversible in the next generation after descendants were withdrawn from chemical stress (i.e., recovery experiment), and whether the lowest test concentration of each chemical induced toxic effects when both concentrations were combined (i.e., mixture experiments). Our results showed that tamoxifen and 4OHTam induced the adverse effects at environmentally relevant concentrations. Tamoxifen and 4OHTam impaired size, viability, reproduction and the r in four generations of treated D. pulex, but these effects were not clearly magnified over generations. Tamoxifen was more potent than 4OHTam on D. pulex. When used in a mixture, the combination of tamoxifen and 4OHTam induced effects in offspring, whereas no effects were observed when these chemicals were tested individually. In the recovery experiment, the reproduction and size were reduced in offspring withdrawn from chemical exposures. Our results suggested that tamoxifen and its metabolite may be a relevant pharmaceutical to consider in risk assessment.
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Affiliation(s)
- Myriam Borgatta
- Institute of Earth Surface Dynamics, University of Lausanne, Switzerland
| | - Patrice Waridel
- Protein Analysis Facility, Center for Integrative Genomics, University of Lausanne, Switzerland
| | - Laurent-Arthur Decosterd
- Division of Clinical Pharmacology and Toxicology, University Hospital Centre of the Canton of Vaud (CHUV), Switzerland
| | - Thierry Buclin
- Protein Analysis Facility, Center for Integrative Genomics, University of Lausanne, Switzerland
| | - Nathalie Chèvre
- Institute of Earth Surface Dynamics, University of Lausanne, Switzerland.
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Tamoxifen promotes differentiation of oligodendrocyte progenitors in vitro. Neuroscience 2016; 319:146-54. [PMID: 26820594 DOI: 10.1016/j.neuroscience.2016.01.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/22/2015] [Accepted: 01/13/2016] [Indexed: 12/12/2022]
Abstract
The most promising therapeutic approach to finding the cure for devastating demyelinating conditions is the identification of clinically safe pharmacological agents that can promote differentiation of endogenous oligodendrocyte precursor cells (OPCs). Here we show that the breast cancer medication tamoxifen (TMX), with well-documented clinical safety and confirmed beneficial effects in various models of demyelinating conditions, stimulates differentiation of rat glial progenitors to mature oligodendrocytes in vitro. Clinically applicable doses of TMX significantly increased both the number of CNPase-positive oligodendrocytes and protein levels of myelin basic protein, measured with Western blots. Furthermore, we also found that OPC differentiation was stimulated, not only by the pro-drug TMX-citrate (TMXC), but also by two main TMX metabolites, 4-hydroxy-TMX and endoxifen. Differentiating effects of TMXC and its metabolites were completely abolished in the presence of estrogen receptor (ER) antagonist, ICI182780. In contrast to TMXC and 4-hydroxy-TMX, endoxifen also induced astrogliogenesis, but independent of the ER activation. In sum, we showed that the TMX prodrug and its two main metabolites (4-hydroxy-TMX and endoxifen) promote ER-dependent oligodendrogenesis in vitro, not reported before. Given that differentiating effects of TMX were achieved with clinically safe doses, TMX is likely one of the most promising FDA-approved drugs for the possible treatment of demyelinating diseases.
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Benedykcinska A, Ferreira A, Lau J, Broni J, Richard-Loendt A, Henriquez NV, Brandner S. Generation of brain tumours in mice by Cre-mediated recombination of neural progenitors in situ with the tamoxifen metabolite endoxifen. Dis Model Mech 2015; 9:211-20. [PMID: 26704996 PMCID: PMC4770146 DOI: 10.1242/dmm.022715] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 12/21/2015] [Indexed: 01/10/2023] Open
Abstract
Targeted cell- or region-specific gene recombination is widely used in the functional analysis of genes implicated in development and disease. In the brain, targeted gene recombination has become a mainstream approach to study neurodegeneration or tumorigenesis. The use of the Cre-loxP system to study tumorigenesis in the adult central nervous system (CNS) can be limited, when the promoter (such as GFAP) is also transiently expressed during development, which can result in the recombination of progenies of different lineages. Engineering of transgenic mice expressing Cre recombinase fused to a mutant of the human oestrogen receptor (ER) allows the circumvention of transient developmental Cre expression by inducing recombination in the adult organism. The recombination of loxP sequences occurs only in the presence of tamoxifen. Systemic administration of tamoxifen can, however, exhibit toxicity and might also recombine unwanted cell populations if the promoter driving Cre expression is active at the time of tamoxifen administration. Here, we report that a single site-specific injection of an active derivative of tamoxifen successfully activates Cre recombinase and selectively recombines tumour suppressor genes in neural progenitor cells of the subventricular zone in mice, and we demonstrate its application in a model for the generation of intrinsic brain tumours.
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Affiliation(s)
- Anna Benedykcinska
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Andreia Ferreira
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Joanne Lau
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Jessica Broni
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Angela Richard-Loendt
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Nico V Henriquez
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Sebastian Brandner
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK Division of Neuropathology, The National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
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Lee O, Ivancic D, Allu S, Shidfar A, Kenney K, Helenowski I, Sullivan ME, Muzzio M, Scholtens D, Chatterton RT, Bethke KP, Hansen NM, Khan SA. Local transdermal therapy to the breast for breast cancer prevention and DCIS therapy: preclinical and clinical evaluation. Cancer Chemother Pharmacol 2015; 76:1235-46. [DOI: 10.1007/s00280-015-2848-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 08/13/2015] [Indexed: 10/22/2022]
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27
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Ribeiro MPC, Santos AE, Custódio JBA. Rethinking tamoxifen in the management of melanoma: New answers for an old question. Eur J Pharmacol 2015; 764:372-378. [PMID: 26165763 DOI: 10.1016/j.ejphar.2015.07.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 06/29/2015] [Accepted: 07/08/2015] [Indexed: 12/18/2022]
Abstract
The use of the antiestrogen tamoxifen in melanoma therapy is controversial due to the unsuccessful outcomes and a still rather unclarified mechanism of action. It seemed that the days of tamoxifen in malignant melanoma therapy were close to an end, but new evidence may challenge this fate. On one hand, it is now believed that metabolism is a major determinant of tamoxifen clinical outcomes in breast cancer patients, which is a variable that has yet to be tested in melanoma patients, since the tamoxifen active metabolite endoxifen demonstrated superior cytostatic activity over the parent drug in melanoma cells; on the other hand, new evidence has emerged regarding estrogen-mediated signaling in melanoma cells, including the methylation of the estrogen receptor-α gene promoter and the expression of the G protein coupled estrogen receptor. The expression of estrogen receptor-α and G protein coupled estrogen receptor, as well as the cytochrome P450 (CYP) 2D6 genotype, may be used as predictive biomarkers to select the patients that may respond to antiestrogens based on specific traits of their tumors. This review focused on these new evidences and how they may contribute to shed new light on this long-lasting controversy, as well as their possible implications for future investigations.
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Affiliation(s)
- Mariana P C Ribeiro
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal.
| | - Armanda E Santos
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - José B A Custódio
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
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28
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Borgatta M, Decosterd LA, Waridel P, Buclin T, Chèvre N. The anticancer drug metabolites endoxifen and 4-hydroxy-tamoxifen induce toxic effects on Daphnia pulex in a two-generation study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 520:232-40. [PMID: 25817760 DOI: 10.1016/j.scitotenv.2015.03.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 02/18/2015] [Accepted: 03/09/2015] [Indexed: 05/17/2023]
Abstract
Although pharmaceutical metabolites are found in the aquatic environment, their toxicity on living organisms is poorly studied in general. Endoxifen and 4-hydroxy-tamoxifen (4OHTam) are two metabolites of the widely used anticancer drug tamoxifen for the prevention and treatment of breast cancers. Both metabolites have a high pharmacological potency in vertebrates, attributing prodrug characteristics to tamoxifen. Tamoxifen and its metabolites are body-excreted by patients, and the parent compound is found in sewage treatment plan effluents and natural waters. The toxicity of these potent metabolites on non-target aquatic species is unknown, which forces environmental risk assessors to predict their toxicity on aquatic species using knowledge on the parent compounds. Therefore, the aim of this study was to assess the sensitivity of two generations of the freshwater microcrustacean Daphnia pulex towards 4OHTam and endoxifen. Two chronic tests of 4OHTam and endoxifen were run in parallel and several endpoints were assessed. The results show that the metabolites 4OHTam and endoxifen induced reproductive and survival effects. For both metabolites, the sensitivity of D. pulex increased in the second generation. The intrinsic rate of natural increase (r) decreased with increasing 4OHTam and endoxifen concentrations. The No-Observed Effect Concentrations (NOECs) calculated for the reproduction of the second generation exposed to 4OHTam and endoxifen were <1.8 and 4.3 μg/L, respectively, whereas the NOECs that were calculated for the intrinsic rate of natural increase were <1.8 and 0.4 μg/L, respectively. Our study raises questions about prodrug and active metabolites in environmental toxicology assessments of pharmaceuticals. Our findings also emphasize the importance of performing long-term experiments and considering multi-endpoints instead of the standard reproduction outcome.
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Affiliation(s)
- Myriam Borgatta
- Institute of Earth Surface Dynamics, University of Lausanne, Switzerland.
| | - Laurent-Arthur Decosterd
- Division of Clinical Pharmacology and Toxicology, University Hospital Centre of the Canton of Vaud (CHUV), Switzerland
| | - Patrice Waridel
- Protein Analysis Facility, Centre for Integrative Genomics, University of Lausanne, Switzerland
| | - Thierry Buclin
- Division of Clinical Pharmacology and Toxicology, University Hospital Centre of the Canton of Vaud (CHUV), Switzerland
| | - Nathalie Chèvre
- Institute of Earth Surface Dynamics, University of Lausanne, Switzerland
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29
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Zhang C, Zhong Q, Zhang Q, Zheng S, Miele L, Wang G. Boronic prodrug of endoxifen as an effective hormone therapy for breast cancer. Breast Cancer Res Treat 2015; 152:283-91. [PMID: 26071758 PMCID: PMC4524496 DOI: 10.1007/s10549-015-3461-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 06/05/2015] [Indexed: 11/25/2022]
Abstract
As a prodrug, tamoxifen is activated by the P450 enzyme CYP2D6 that is responsible for converting it to the active metabolites, 4-hydroxytamoxifen and endoxifen. Patients with genetic polymorphisms of CYP2D6 may not receive the full benefit of tamoxifen therapy. There is increasing evidence that poor metabolizer patients have lower plasma concentrations of endoxifen and suffer worse disease outcome, although some clinical studies reported no correlation between CYP2D6 polymorphism and tamoxifen therapy outcome. Endoxifen is currently undergoing clinical trials as a potentially improved and more potent SERM (Selective Estrogen Receptor Modulator) for endocrine therapy that is independent of CYP2D6 status in patients. However, direct administration of endoxifen may present the problem of low bioavailability due to its rapid first-pass metabolism via O-glucuronidation. We have designed and synthesized ZB483, a boronic prodrug of endoxifen suitable for oral administration with greatly enhanced bioavailability by increasing the concentration of endoxifen in mouse blood. Our study demonstrated that ZB483 potently inhibited growth of ER+ breast cancer cells in vitro and was efficiently converted to endoxifen in cell culture media by oxidative deboronation. This metabolic conversion is equally efficient in vivo as indicated in the pharmacokinetic study in mice. Moreover, when administered at the same dose, oral ZB483 afforded a 30- to 40-fold higher plasma level of endoxifen in mice than oral administration of endoxifen. The significantly enhanced bioavailability of endoxifen conferred by the boronic prodrug was further validated in an in vivo efficacy study. ZB483 was demonstrated to be more efficacious than endoxifen in inhibiting xenograft tumor growth in mice at equal dosage but more so at lower dosage. Together, these preclinical studies demonstrate that ZB483 is a promising endocrine therapy agent with markedly enhanced bioavailability in systemic circulation and superior efficacy compared to endoxifen.
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Affiliation(s)
- Changde Zhang
- RCMI Cancer Research Center, Xavier University of Louisiana, New Orleans, LA, 70125, USA
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30
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ter Heine R, Binkhorst L, de Graan AJM, de Bruijn P, Beijnen JH, Mathijssen RHJ, Huitema ADR. Population pharmacokinetic modelling to assess the impact of CYP2D6 and CYP3A metabolic phenotypes on the pharmacokinetics of tamoxifen and endoxifen. Br J Clin Pharmacol 2015; 78:572-86. [PMID: 24697814 DOI: 10.1111/bcp.12388] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 03/25/2014] [Indexed: 12/12/2022] Open
Abstract
AIMS Tamoxifen is considered a pro-drug of its active metabolite endoxifen. The major metabolic enzymes involved in endoxifen formation are CYP2D6 and CYP3A. There is considerable evidence that variability in activity of these enzymes influences endoxifen exposure and thereby may influence the clinical outcome of tamoxifen treatment. We aimed to quantify the impact of metabolic phenotype on the pharmacokinetics of tamoxifen and endoxifen. METHODS We assessed the CYP2D6 and CYP3A metabolic phenotypes in 40 breast cancer patients on tamoxifen treatment with a single dose of dextromethorphan as a dual phenotypic probe for CYP2D6 and CYP3A. The pharmacokinetics of dextromethorphan, tamoxifen and their relevant metabolites were analyzed using non-linear mixed effects modelling. RESULTS Population pharmacokinetic models were developed for dextromethorphan, tamoxifen and their metabolites. In the final model for tamoxifen, the dextromethorphan derived metabolic phenotypes for CYP2D6 as well as CYP3A significantly (P < 0.0001) explained 54% of the observed variability in endoxifen formation (inter-individual variability reduced from 55% to 25%). CONCLUSIONS We have shown that not only CYP2D6, but also CYP3A enzyme activity influences the tamoxifen to endoxifen conversion in breast cancer patients. Our developed model may be used to assess separately the impact of CYP2D6 and CYP3A mediated drug-drug interactions with tamoxifen without the necessity of administering this anti-oestrogenic drug and to support Bayesian guided therapeutic drug monitoring of tamoxifen in routine clinical practice.
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Affiliation(s)
- Rob ter Heine
- Department of Clinical Pharmacy, Meander Medical Center, Amersfoort, The Netherlands
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31
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Chanawong A, Hu DG, Meech R, Mackenzie PI, McKinnon RA. Induction of UDP-glucuronosyltransferase 2B15 gene expression by the major active metabolites of tamoxifen, 4-hydroxytamoxifen and endoxifen, in breast cancer cells. Drug Metab Dispos 2015; 43:889-97. [PMID: 25795461 DOI: 10.1124/dmd.114.062935] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/19/2015] [Indexed: 11/22/2022] Open
Abstract
We previously reported upregulation of UGT2B15 by 17β-estradiol in breast cancer MCF7 cells via binding of the estrogen receptor α (ERα) to an estrogen response unit (ERU) in the proximal UGT2B15 promoter. In the present study, we show that this ERα-mediated upregulation was significantly reduced by two ER antagonists (fulvestrant and raloxifene) but was not affected by a third ER antagonist, 4-hydroxytamoxifen (4-OHTAM), a major active tamoxifen (TAM) metabolite. Furthermore, we found that, similar to 17β-estradiol, 4-OHTAM and endoxifen (another major active TAM metabolite) elevated UGT2B15 mRNA levels, and that this stimulation was significantly abrogated by fulvestrant. Further experiments using 4-OHTAM revealed a critical role for ERα in this regulation. Specifically; knockdown of ERα expression by anti-ERα small interfering RNA reduced the 4-OHTAM-mediated induction of UGT2B15 expression; 4-OHTAM activated the wild-type but not the ERU-mutated UGT2B15 promoter; and chromatin immunoprecipitation assays showed increased ERα occupancy at the UGT2B15 ERU in MCF7 cells upon exposure to 4-OHTAM. Together, these data indicate that both 17β-estradiol and the antiestrogen 4-OHTAM upregulate UGT2B15 in MCF7 cells via the same ERα-signaling pathway. This is consistent with previous observations that both 17β-estradiol and TAM upregulate a common set of genes in MCF7 cells via the ER-signaling pathway. As 4-OHTAM is a UGT2B15 substrate, the upregulation of UGT2B15 by 4-OHTAM in target breast cancer cells is likely to enhance local metabolism and inactivation of 4-OHTAM within the tumor. This represents a potential mechanism that may reduce TAM therapeutic efficacy or even contribute to the development of acquired TAM resistance.
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Affiliation(s)
- Apichaya Chanawong
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University School of Medicine, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Dong Gui Hu
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University School of Medicine, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Robyn Meech
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University School of Medicine, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Peter I Mackenzie
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University School of Medicine, Flinders Medical Centre, Bedford Park, South Australia, Australia
| | - Ross A McKinnon
- Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, Flinders University School of Medicine, Flinders Medical Centre, Bedford Park, South Australia, Australia
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32
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Binkhorst L, Mathijssen RH, Jager A, van Gelder T. Individualization of tamoxifen therapy: Much more than just CYP2D6 genotyping. Cancer Treat Rev 2015; 41:289-99. [DOI: 10.1016/j.ctrv.2015.01.002] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 12/30/2014] [Accepted: 01/07/2015] [Indexed: 12/12/2022]
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Saladores P, Mürdter T, Eccles D, Chowbay B, Zgheib NK, Winter S, Ganchev B, Eccles B, Gerty S, Tfayli A, Lim JSL, Yap YS, Ng RCH, Wong NS, Dent R, Habbal MZ, Schaeffeler E, Eichelbaum M, Schroth W, Schwab M, Brauch H. Tamoxifen metabolism predicts drug concentrations and outcome in premenopausal patients with early breast cancer. THE PHARMACOGENOMICS JOURNAL 2015; 15:84-94. [PMID: 25091503 PMCID: PMC4308646 DOI: 10.1038/tpj.2014.34] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 04/30/2014] [Accepted: 06/04/2014] [Indexed: 12/11/2022]
Abstract
Tamoxifen is the standard-of-care treatment for estrogen receptor-positive premenopausal breast cancer. We examined tamoxifen metabolism via blood metabolite concentrations and germline variations of CYP3A5, CYP2C9, CYP2C19 and CYP2D6 in 587 premenopausal patients (Asians, Middle Eastern Arabs, Caucasian-UK; median age 39 years) and clinical outcome in 306 patients. N-desmethyltamoxifen (DM-Tam)/(Z)-endoxifen and CYP2D6 phenotype significantly correlated across ethnicities (R(2): 53%, P<10(-77)). CYP2C19 and CYP2C9 correlated with norendoxifen and (Z)-4-hydroxytamoxifen concentrations, respectively (P<0.001). DM-Tam was influenced by body mass index (P<0.001). Improved distant relapse-free survival (DRFS) was associated with decreasing DM-Tam/(Z)-endoxifen (P=0.036) and increasing CYP2D6 activity score (hazard ratio (HR)=0.62; 95% confidence interval (CI), 0.43-0.91; P=0.013). Low (<14 nM) compared with high (>35 nM) endoxifen concentrations were associated with shorter DRFS (univariate P=0.03; multivariate HR=1.94; 95% CI, 1.04-4.14; P=0.064). Our data indicate that endoxifen formation in premenopausal women depends on CYP2D6 irrespective of ethnicity. Low endoxifen concentration/formation and decreased CYP2D6 activity predict shorter DRFS.
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Affiliation(s)
- P Saladores
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - T Mürdter
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - D Eccles
- Faculty of Medicine, Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, University of Southampton, Southampton, UK
- University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - B Chowbay
- Clinical Pharmacology Laboratory, Division of Medical Sciences, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore, Singapore
- Academic Medicine Research Institute, Office of Clinical Sciences, Duke-NUS Graduate Medical School Singapore, Singapore, Singapore
- SingHealth Clinical Pharmacology Core, Academia, Singapore Health Services, Singapore, Singapore
| | - N K Zgheib
- Faculty of Medicine, Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
| | - S Winter
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - B Ganchev
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - B Eccles
- Faculty of Medicine, Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, University of Southampton, Southampton, UK
- University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - S Gerty
- Faculty of Medicine, Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, University of Southampton, Southampton, UK
- University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - A Tfayli
- Hematology-Oncology Division, Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - J S L Lim
- Clinical Pharmacology Laboratory, Division of Medical Sciences, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore, Singapore
| | - Y S Yap
- Department of Medical Oncology, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore, Singapore
| | - R C H Ng
- Department of Medical Oncology, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore, Singapore
| | - N S Wong
- Department of Medical Oncology, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore, Singapore
| | - R Dent
- Department of Medical Oncology, Humphrey Oei Institute of Cancer Research, National Cancer Centre Singapore, Singapore, Singapore
| | - M Z Habbal
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - E Schaeffeler
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - M Eichelbaum
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - W Schroth
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - M Schwab
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- Department of Clinical Pharmacology, University Hospital Tübingen, Tübingen, Germany
- German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - H Brauch
- Dr Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
- German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany
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Blackburn HL, Ellsworth DL, Shriver CD, Ellsworth RE. Role of cytochrome P450 genes in breast cancer etiology and treatment: effects on estrogen biosynthesis, metabolism, and response to endocrine therapy. Cancer Causes Control 2015; 26:319-32. [PMID: 25554091 DOI: 10.1007/s10552-014-0519-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 12/19/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE The cytochrome P450 (CYP) genes are oxygenases involved in estrogen biosynthesis and metabolism, generation of DNA damaging procarcinogens, and response to anti-estrogen therapies. Since lifetime estrogen exposure is an established risk factor for breast cancer, determining the role of CYP genes in breast cancer etiology may provide critical information for understanding tumorigenesis and response to treatment. METHODS This review summarizes literature available in PubMed published between 1993 and 2013 that focuses on studies evaluating the effects of DNA variants in CYP genes on estrogen synthesis, metabolism, and generation of procarcinogens in addition to response to anti-estrogen therapies. RESULTS Evaluation of DNA variants in estrogen metabolism genes was largely inconclusive. Meta-analyses of data from CYP19A1 support an association between the number of (TTTA) n repeats in intron 4 and breast cancer risk, but the biological mechanism for this relationship is unknown. Associations between single nucleotide polymorphism in CYP1B1 and DNA damage caused by procarcinogenic estrogen metabolites were ambiguous. Variants in CYP2D6 are associated with altered metabolism tamoxifen; however, current data do not support widespread clinical testing. The effect of variants in CYP19A1 in response to aromatase inhibitors is also questionable. CONCLUSION Evaluation of DNA variants in CYP genes involved with estrogen metabolism or treatment response has been inconclusive, reflecting small samples sizes, tumor heterogeneity, and differences between populations. Better-powered studies that account for genetic backgrounds and tumor phenotypes are thus necessary.
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Abstract
Depression, anxiety, delirium, and other psychiatric symptoms are highly prevalent in the cancer setting, and pharmacological intervention is an important component in the overall psychosocial care of the patient. Psychopharmacology is also used as a primary or adjuvant treatment for the management of cancer-related symptoms stemming from the disease itself and/or its treatment, including sleep disturbance, loss of appetite, neuropathic pain, nausea, fatigue, and hot flashes. Psychiatrists, oncologists, and palliative care physicians working as members of a multidisciplinary team have the opportunity to target multiple symptoms that negatively affect a patient's quality of life with the strategic use of psychotropic medications when deemed appropriate. This article aims to review the indications for use of antidepressants, psychostimulants, anxiolytics, antipsychotics, and mood stabilizers in oncology. An updated review of the relevant literature is discussed and referenced in each section.
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Affiliation(s)
- Seema M Thekdi
- The University of Texas MD Anderson Cancer Center, P.O. Box 301402, Unit 1454, Houston, TX, 77230-1402, USA,
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Schweikart KM, Eldridge SR, Safgren SL, Parman T, Reid JM, Ames MM, Goetz MP, Davis MA. Comparative uterotrophic effects of endoxifen and tamoxifen in ovariectomized Sprague-Dawley rats. Toxicol Pathol 2014; 42:1188-96. [PMID: 24670817 PMCID: PMC4177029 DOI: 10.1177/0192623314525688] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Endoxifen (4-hydroxy-N-desmethyl-tamoxifen), one of the major active metabolites of tamoxifen, has substantially greater estrogen antagonist properties and antiproliferative effects in breast tumor cells than tamoxifen, a mixed estrogen agonist/antagonist. An associated risk of endometrial cancer and hyperplasia has been linked to the estrogen agonist properties of tamoxifen. We evaluated endoxifen using a classic uterotrophic effects method. Rats were given endoxifen or tamoxifen orally for 3 days. Estradiol was the positive control. Endoxifen and tamoxifen plasma levels exceeded those previously observed clinically. Uterine weight was 3-fold higher in the estradiol group than in the tamoxifen or endoxifen groups, which did not differ from vehicle controls. Tamoxifen and endoxifen caused a greater increase in luminal epithelial cell height than estradiol. Both tamoxifen and endoxifen produced an increase in the stromal BrdU labeling index (LI) that was ≤ estradiol and inversely related to dose, but did not affect luminal epithelial cell BrdU LI. As expected, estradiol increased luminal epithelial cell proliferation. These results indicate that endoxifen induces uterotrophic effects, but is less potent than estradiol in eliciting these effects. Given prior preclinical observations that endoxifen has superior antitumor activity than tamoxifen, the observations of similar uterine effects suggest that the endoxifen risk/benefit ratio may be superior to tamoxifen.
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Affiliation(s)
- Karen M Schweikart
- Developmental Therapeutics Program, National Cancer Institute, Bethesda, Maryland, USA
| | - Sandy R Eldridge
- Charles River Laboratories Pathology Associates, Frederick, Maryland, USA Present address: Developmental Therapeutics Program, National Cancer Institute, Bethesda, MD, USA
| | | | | | | | | | | | - Myrtle A Davis
- Developmental Therapeutics Program, National Cancer Institute, Bethesda, Maryland, USA
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Ribeiro MPC, Santos AE, Custódio JBA. Mitochondria: the gateway for tamoxifen-induced liver injury. Toxicology 2014; 323:10-8. [PMID: 24881593 DOI: 10.1016/j.tox.2014.05.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 05/14/2014] [Accepted: 05/28/2014] [Indexed: 12/13/2022]
Abstract
Tamoxifen (TAM) is routinely used in the treatment of breast carcinoma. TAM-induced liver injury remains a major concern, as TAM causes hepatic steatosis in a significant number of patients, which can progress toward steatohepatitis. Liver toxicity is generally believed to involve mitochondrial dysfunction and TAM exerts multiple deleterious effects on mitochondria, which may account for the hepatotoxicity observed in patients treated with TAM. Endoxifen (EDX), a key active metabolite of TAM that is being investigated as an alternative to TAM in breast cancer therapy, slightly affects mitochondria in comparison with TAM and this demonstration well correlates with the absence of alterations in the clinical parameters of individuals taking EDX. The steady-state plasma concentrations of TAM and its active metabolites EDX and 4-hydroxytamoxifen (OHTAM) in patients taking TAM are highly variable, reflecting genetic variants of CYP2D6 involved in TAM metabolism. Besides de genetic polymorphisms, the intake of drugs that influence the enzymatic activity of CYP2D6 compromises the therapeutic efficiency of TAM. The knowledge of the impact of the variability of TAM metabolism in the breast cancer treatment explains the discrepant outcomes observed in patients taking TAM, as well as the individual variability of idiosyncratic liver injury and other sides effects observed. Therefore, and contrarily to the clinical use of EDX, the need of therapeutic drug monitoring and a regular assessment of liver function biomarkers should be considered in patients under therapies with TAM. In this review we focus on the mitochondrial effects of TAM and its metabolites and on the role played by mitochondria in the initiating events leading to TAM-induced hepatotoxicity, as well as the clinical implications.
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Affiliation(s)
- Mariana P C Ribeiro
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Armanda E Santos
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - José B A Custódio
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal.
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Dickschen K, Eissing T, Mürdter T, Schwab M, Willmann S, Hempel G. Concomitant use of tamoxifen and endoxifen in postmenopausal early breast cancer: prediction of plasma levels by physiologically-based pharmacokinetic modeling. SPRINGERPLUS 2014; 3:285. [PMID: 24936398 PMCID: PMC4058004 DOI: 10.1186/2193-1801-3-285] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 05/28/2014] [Indexed: 11/10/2022]
Abstract
Purpose To overcome cytochrome P450 2D6 (CYP2D6) mediated tamoxifen resistance in postmenopausal early breast cancer, CYP2D6 phenotype-adjusted tamoxifen dosing in patients with impaired CYP2D6 metabolism and/or the application of endoxifen, the most potent tamoxifen metabolite, are alternative treatment options. To elucidate both strategies comprehensively we used a physiologically-based pharmacokinetic (PBPK) modeling approach. Methods Firstly simulation of increasing tamoxifen dosages was performed by a virtual clinical trial including populations of CYP2D6 poor (PM), intermediate (IM) and extensive metabolizers (EM) (N = 8,000). Secondly we performed PBPK-simulations under consideration of tamoxifen use plus concomitant increasing dosages of endoxifen (N = 7,000). Results Our virtual study demonstrates that dose escalation of tamoxifen in IMs resulted in endoxifen steady-state plasma concentrations similar to CYP2D6 EMs whereas PMs did not reach EM endoxifen levels. Steady-state plasma concentrations of tamoxifen, N-desmethyl-tamoxifen, 4-hydroxy-tamoxifen and endoxifen were similar in CYP2D6 IMs and PMs versus EMs using once daily dosing of 20 mg tamoxifen and concomitant CYP2D6 phenotype-adjusted endoxifen dosing in IMs and PMs (1 mg/d and 3 mg/d, respectively). Conclusion In conclusion, we suggest that co-administration of endoxifen in tamoxifen treated early breast cancer women with impaired CYP2D6 metabolism is a promising alternative to reach plasma concentrations comparable to CYP2D6 EM patients.
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Affiliation(s)
- Kristin Dickschen
- Institut für Pharmazeutische und Medizinische Chemie, Klinische Pharmazie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 48, Münster, 48149 Germany ; Computational Systems Biology, Bayer Technology Services GmbH, Building 9115, Leverkusen, 51368 Germany
| | - Thomas Eissing
- Computational Systems Biology, Bayer Technology Services GmbH, Building 9115, Leverkusen, 51368 Germany
| | - Thomas Mürdter
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology and University Tübingen, Auerbachstrasse 112, Stuttgart, 70376 Germany
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology and University Tübingen, Auerbachstrasse 112, Stuttgart, 70376 Germany ; Department of Clinical Pharmacology, University Hospital Tübingen, Auf der Morgenstelle 8, Tübingen, 72076 Germany
| | - Stefan Willmann
- Computational Systems Biology, Bayer Technology Services GmbH, Building 9115, Leverkusen, 51368 Germany ; Clinical Pharmacometrics, Bayer Pharma AG, Aprather Weg 18a, Wuppertal, 42113 Germany
| | - Georg Hempel
- Institut für Pharmazeutische und Medizinische Chemie, Klinische Pharmazie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 48, Münster, 48149 Germany
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Stokes G, Conboy JC. Measuring selective estrogen receptor modulator (SERM)-membrane interactions with second harmonic generation. J Am Chem Soc 2014; 136:1409-17. [PMID: 24410282 PMCID: PMC4004268 DOI: 10.1021/ja409250y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Indexed: 12/29/2022]
Abstract
The interaction of selective estrogen receptor modulators (SERMs) with lipid membranes has been measured at clinically relevant serum concentrations using the label-free technique of second harmonic generation (SHG). The SERMs investigated in this study include raloxifene, tamoxifen, and the tamoxifen metabolites 4-hydroxytamoxifen, N-desmethyltamoxifen, and endoxifen. Equilibrium association constants (Ka) were measured for SERMs using varying lipid compositions to examine how lipid phase, packing density, and cholesterol content impact SERM-membrane interactions. Membrane-binding properties of tamoxifen and its metabolites were compared on the basis of hydroxyl group substitution and amine ionization to elucidate how the degree of drug ionization impacts membrane partitioning. SERM-membrane interactions were probed under multiple pH conditions, and drug adsorption was observed to vary with the concentration of soluble neutral species. The agreement between Ka values derived from SHG measurements of the interactions between SERMs and artificial cell membranes and independent observations of the SERMs efficacy from clinical studies suggests that quantifying membrane adsorption properties may be important for understanding SERM action in vivo.
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Affiliation(s)
- Grace
Y. Stokes
- Department
of Chemistry, University of Utah, 315 South 1400 East, Room 2020, Salt Lake
City, Utah 84112, United States
| | - John C. Conboy
- Department
of Chemistry, University of Utah, 315 South 1400 East, Room 2020, Salt Lake
City, Utah 84112, United States
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Development of new estrogen receptor-targeting therapeutic agents for tamoxifen-resistant breast cancer. Future Med Chem 2013; 5:1023-35. [PMID: 23734685 DOI: 10.4155/fmc.13.63] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Despite our deepening understanding of the mechanisms of resistance and intensive efforts to develop therapeutic solutions to combat resistance, de novo and acquired tamoxifen resistance remains a clinical challenge, and few effective regimens exist to treat tamoxifen-resistant breast cancer. The complexity of tamoxifen resistance calls for diverse therapeutic approaches. This review presents several therapeutic strategies and lead compounds targeting the estrogen receptor signaling pathways for treatment of tamoxifen-resistant breast cancer, with a critical assessment of challenges and potentials regarding clinical outcome. Medicinal chemistry holds the key to effective, personalized combination therapy for tamoxifen-resistant breast cancer by making available a diverse arsenal of small-molecule drugs that specifically target signaling pathways modulating hormone resistance. These combination therapy candidates should have the desired specificity, selectivity and low toxicity to resensitize tumor response to tamoxifen and/or inhibit the growth and proliferation of resistant breast cancer cells.
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Güngör S, Delgado-Charro MB, Masini-Etévé V, Potts RO, Guy RH. Transdermal flux predictions for selected selective oestrogen receptor modulators (SERMs): Comparison with experimental results. J Control Release 2013; 172:601-6. [DOI: 10.1016/j.jconrel.2013.09.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 09/03/2013] [Accepted: 09/19/2013] [Indexed: 11/28/2022]
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Berliere M, Duhoux FP, Dalenc F, Baurain JF, Dellevigne L, Galant C, Van Maanen A, Piette P, Machiels JP. Tamoxifen and ovarian function. PLoS One 2013; 8:e66616. [PMID: 23840510 PMCID: PMC3695994 DOI: 10.1371/journal.pone.0066616] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 05/07/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Some studies suggest that the clinical parameter "amenorrhea" is insufficient to define the menopausal status of women treated with chemotherapy or tamoxifen. In this study, we investigated and compared the ovarian function defined either by clinical or biological parameters in pre-menopausal breast cancer patients treated with tamoxifen administered as adjuvant therapy. MATERIALS AND METHODS Between 1999 and 2003, 138 premenopausal patients consecutively treated for early breast cancer were included. Sixty-eight received tamoxifen in monotherapy as the only adjuvant systemic treatment (Group I) and 70 were treated with tamoxifen after adjuvant chemotherapy (Group II). All patients had a confirmed premenopausal status based on clinical parameters and hormonal values at study entry. They were followed prospectively every 3 months for 3 years: menses data, physical examination and blood tests (LH, FSH, 17-beta-estradiol). Vaginal ultrasonography was carried out every 6 months. After 3 years, prospective evaluation was completed and monitoring of ovarian function was performed as usual in our institution (1x/year). All data were retrospectively evaluated in 2011. RESULTS Three patients were excluded from the study in group I and 2 were excluded in group II. Patients were divided into 4 subgroups according to clinical data, i.e. menses patterns. These patterns were assessed by questionnaires. a: Regular menses (>10 cycles/year) b: Oligomenorrhea (5 to 9 cycles/year) c: Severe oligomenorrhea (1 to 4 cycles/year) d: Complete amenorrhea Estrogen levels did not appear to have any impact on disease-free survival rates after 3 or 8 years. FSH values were also documented and analyzed. They exhibited the same profile as estradiol values. CONCLUSIONS Amenorrhea is an insufficient parameter to define menopausal status in patients receiving tamoxifen. Low estradiol levels must be coupled with other biological parameters to characterize endocrine status. These data are very important for the choice of endocrine therapy.
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Affiliation(s)
- Martine Berliere
- Clinique du sein, Centre du Cancer, Cliniques universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium.
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Ribeiro MPC, Silva FSG, Paixão J, Santos AE, Custódio JBA. The combination of the antiestrogen endoxifen with all-trans-retinoic acid has anti-proliferative and anti-migration effects on melanoma cells without inducing significant toxicity in non-neoplasic cells. Eur J Pharmacol 2013; 715:354-62. [PMID: 23712006 DOI: 10.1016/j.ejphar.2013.04.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 04/24/2013] [Accepted: 04/26/2013] [Indexed: 10/26/2022]
Abstract
Melanoma incidence is dramatically increasing and the available treatments beyond partial efficacy have severe side effects. Retinoids are promising anticancer agents, but their clinical use has been limited by their toxicity, although a combination with other agents can possibly generate a therapeutic action at lower dosage. Thus, we investigated the effects of all-trans-retinoic acid combined with the antiestrogen endoxifen on melanoma cell proliferation and the effects were compared with its pro-drug tamoxifen. Moreover, we evaluated the effects of these combinations on non-neoplasic cells and assessed mitochondrial bioenergetic functions, to predict their potential toxicity. Individually, all-trans-retinoic acid and the antiestrogens endoxifen and tamoxifen decreased melanoma cell biomass, cell viability and DNA synthesis, without increased cell death, suggesting that the compounds inhibited cell proliferation. Noteworthy, endoxifen decreased cell proliferation more efficiently than tamoxifen. The combination of endoxifen with all-trans-retinoic acid enhanced the antiproliferative effects of the compounds individually more potently than tamoxifen, which did not enhance the effects induced by all-trans-retinoic acid alone, and blocked cell cycle progression in G1. Moreover, the combination of all-trans-retinoic acid with endoxifen significantly decreased melanoma cells migration, whereas the combination with tamoxifen did not present significant effects. At the concentrations used the compounds did not induce cytotoxicity in non-neoplasic cells and liver mitochondrial bioenergetic function was not affected. Altogether, our results show for the first time that a combined treatment of all-trans-retinoic acid with endoxifen may provide an anti-proliferative and anti-migration effect upon melanoma cells without major toxicity, offering a powerful therapeutic strategy for malignant melanoma.
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Affiliation(s)
- Mariana P C Ribeiro
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal
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Determination of clinically therapeutic endoxifen concentrations based on efficacy from human MCF7 breast cancer xenografts. Breast Cancer Res Treat 2013; 139:61-9. [DOI: 10.1007/s10549-013-2530-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 04/06/2013] [Indexed: 10/26/2022]
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Abstract
The past decade has brought together substantial advances in human genome analysis and a maturation of understanding of tumor biology. Although there is much progress still to be made, there are now several prominent examples in which tumor-associated somatic mutations have been used to identify cellular signaling pathways in tumors. This in turn has led to the development of targeted therapies, with somatic mutations serving as genomic predictors of tumor response and providing new leads for drug development. There is also a realization that germline DNA variants can help optimize cancer drug dosing and predict the susceptibility of patients to the adverse side effects of these drugs-knowledge that ultimately can be used to improve the benefit:risk ratio of cancer treatment for individual patients.
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Affiliation(s)
- Howard L McLeod
- Institute for Pharmacogenomics and Individualized Therapy, University of North Carolina, Chapel Hill, NC 27599, USA.
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Ribeiro MP, Silva FS, Santos AE, Santos MS, Custódio JB. The antiestrogen endoxifen protects rat liver mitochondria from permeability transition pore opening and oxidative stress at concentrations that do not affect the phosphorylation efficiency. Toxicol Appl Pharmacol 2013; 267:104-12. [DOI: 10.1016/j.taap.2012.12.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 11/30/2012] [Accepted: 12/03/2012] [Indexed: 12/18/2022]
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The use of the 13C-dextromethorphan breath test for phenotyping CYP2D6 in breast cancer patients using tamoxifen: association with CYP2D6 genotype and serum endoxifen levels. Cancer Chemother Pharmacol 2012; 71:593-601. [PMID: 23228987 DOI: 10.1007/s00280-012-2034-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 11/13/2012] [Indexed: 12/31/2022]
Abstract
PURPOSE Adjuvant therapy with tamoxifen significantly reduces breast cancer recurrence and mortality in estrogen receptor positive disease. CYP2D6 is the main enzyme involved in the activation of the prodrug tamoxifen into the anti-estrogen endoxifen. Endoxifen is thought to be a main determinant for clinical efficacy in breast cancer patients using tamoxifen. As the large interindividual variation in endoxifen levels is only partly explained by CYP2D6 genotype, we explored the use of the (13)C-dextromethorphan breath test (DM-BT) for phenotyping CYP2D6 and to predict serum steady-state endoxifen levels as a marker for clinical outcome in breast cancer patients using tamoxifen. METHODS In 65 patients with early breast cancer using tamoxifen, CYP2D6 phenotype was assessed by DM-BT. CYP2D6 genotype using Amplichip and serum steady-state levels of endoxifen were determined. Genotype was translated into the gene activity score and into ultrarapid, extensive, heterozygous extensive, intermediate or poor metabolizer CYP2D6 predicted phenotype. RESULTS CYP2D6 phenotype determined by the DM-BT explained variation in serum steady-state endoxifen levels for 47.5% (R(2) = 0.475, p < 0.001). Positive and negative predictive values for a recently suggested threshold serum level of endoxifen (5.97 ng/mL) for breast cancer recurrence rate were 100 and 90%, respectively, for both CYP2D6 phenotype by DM-BT (delta-over-baseline at t = 50 min (DOB(50)) values of 0.7-0.9) and genotype (CYP2D6 gene activity score of 1.0). CONCLUSION DM-BT might be, along with CYP2D6 genotyping, of value in selection of individualized endocrine therapy in patients with early breast cancer, especially when concomitant use of CYP2D6 inhibiting medication alters the phenotype.
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Mah CS, Kochhar JS, Ong PS, Kang L. A miniaturized flow-through cell to evaluate skin permeation of endoxifen. Int J Pharm 2012; 441:433-40. [PMID: 23174412 DOI: 10.1016/j.ijpharm.2012.11.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 10/11/2012] [Accepted: 11/09/2012] [Indexed: 11/26/2022]
Abstract
Endoxifen, an anti-estrogenic agent, has been recently implicated in the use of breast cancer. Its physicochemical properties make it a good candidate for transdermal delivery. However, as an investigative drug, its limited supply makes it difficult to conduct extensive pre-formulation studies. To address this issue, a miniaturized flow-through diffusion cell has been fabricated that utilized minimal amounts of the drug for in vitro skin permeation studies. The novel flow-through cells have been validated against horizontal diffusion cells and shown to cause no noticeable damage to the applied skin, as observed by histological sectioning. The cells were also demonstrated to be useful in search of suitable enhancers for endoxifen. Endoxifen permeation using permeation enhancers was tested by using this new device and limonene was found to achieve highest flux, attaining the requirement for clinical applications. The fabricated cells can thus be useful in carrying out pre-formulation studies for expensive, new drug entities, both in industrial as well as academic research.
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Affiliation(s)
- Choon Siong Mah
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, 117543, Singapore
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Huber-Wechselberger AE, Niedetzky P, Aigner I, Haschke-Becher E. Impact of CYP2D6 polymorphism on tamoxifen therapy: where are we? Wien Med Wochenschr 2012; 162:252-61. [PMID: 22688624 DOI: 10.1007/s10354-012-0118-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 03/20/2012] [Indexed: 01/06/2023]
Abstract
Tamoxifen is a mainstay in the treatment of hormone-receptor sensitive breast cancer. To be effective, it needs conversion into 4-hydroxy-tamoxifen and endoxifen. The key enzyme involved is encoded by the gene CYP2D6 of which several, sometimes population-specific alleles are known. Corresponding enzyme variants may result in poor, intermediate, and extensive metabolization and therefore different steady-state plasma levels of active metabolites. Those are hypothesized to be linked to clinical outcomes of tamoxifen therapy. However, a wealth of mostly retrospective cohort studies came up with conflicting results. Appraisal of these studies is difficult and a metaanalysis impossible due to heterogeneity of patient populations, disease factors, treatment modalities, and measured outcomes. As standardization would not overcome intrinsic limitations of retrospective analyses, prospective trials comparing genotype-guided versus unsighted tamoxifen treatment are required to prove whether routine CYP2D6 genotyping is clinically effective and cost-effective.
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Affiliation(s)
- Ariana E Huber-Wechselberger
- Competence Center of Molecular Biology and Genetics, Elisabethinen Hospital Linz GmbH, Fadingerstrasse 1, 4020, Linz, Austria.
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Genetic polymorphisms of CYP2D6 increase the risk for recurrence of breast cancer in patients receiving tamoxifen as an adjuvant therapy. Cancer Chemother Pharmacol 2012; 70:75-81. [DOI: 10.1007/s00280-012-1891-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2012] [Accepted: 05/09/2012] [Indexed: 10/28/2022]
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