{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["de Vries Schultink AH"],"funding":["Genentech","GlaxoSmithKline","National Cancer Institute","NCI NIH HHS","A Sister's Hope","Novartis"],"pagination":["567-574"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC5812686"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["161(3)"],"pubmed_abstract":["Purpose
Endoxifen concentrations have been associated with breast cancer recurrence in tamoxifen-treated patients. However, tamoxifen itself and other metabolites also show antiestrogenic anti-tumor activity. Therefore, the aim of this study was to develop a comprehensive Antiestrogenic Activity Score (AAS), which accounts for concentration and antiestrogenic activity of tamoxifen and three metabolites. An association between the AAS and recurrence-free survival was investigated and compared to a previously published threshold for endoxifen concentrations of 5.97 ng/mL.Patients and methods
The antiestrogenic activities of tamoxifen, (Z)-endoxifen, (Z)-4-hydroxytamoxifen, and N-desmethyltamoxifen were determined in a cell proliferation assay. The AAS was determined by calcul"],"journal":["Breast cancer research and treatment"],"pubmed_title":["An Antiestrogenic Activity Score for tamoxifen and its metabolites is associated with breast cancer outcome."],"pmcid":["PMC5812686"],"funding_grant_id":["P30 CA023100","CA166293","R01 CA069375","R01 CA166293"],"pubmed_authors":["Huitema AD","Madlensky L","Pierce JP","Alexi X","van Werkhoven E","Zwart W","de Vries Schultink AH","Natarajan L","Linn SC","Wu AH","Flatt SW","Parker BA","Beijnen JH"],"additional_accession":[]},"is_claimable":false,"name":"An Antiestrogenic Activity Score for tamoxifen and its metabolites is associated with breast cancer outcome.","description":"Purpose
Endoxifen concentrations have been associated with breast cancer recurrence in tamoxifen-treated patients. However, tamoxifen itself and other metabolites also show antiestrogenic anti-tumor activity. Therefore, the aim of this study was to develop a comprehensive Antiestrogenic Activity Score (AAS), which accounts for concentration and antiestrogenic activity of tamoxifen and three metabolites. An association between the AAS and recurrence-free survival was investigated and compared to a previously published threshold for endoxifen concentrations of 5.97 ng/mL.Patients and methods
The antiestrogenic activities of tamoxifen, (Z)-endoxifen, (Z)-4-hydroxytamoxifen, and N-desmethyltamoxifen were determined in a cell proliferation assay. The AAS was determined by calcul","dates":{"release":"2017-01-01T00:00:00Z","publication":"2017 Feb","modification":"2025-04-04T23:17:21.508Z","creation":"2019-03-26T23:02:17Z"},"accession":"S-EPMC5812686","cross_references":{"pubmed":["28005246"],"doi":["10.1007/s10549-016-4083-6"]}}