Postmenopausal circulating levels of 2- and 16α-hydroxyestrone and risk of endometrial cancer.

Content Provider	Europe PMC
Author	Zeleniuch-Jacquotte, A Shore, R E Afanasyeva, Y Lukanova, A Sieri, S Koenig, K L Idahl, A Krogh, V Liu, M Ohlson, N Muti, P Arslan, A A Lenner, P Berrino, F Hallmans, G Toniolo, P Lundin, E
Copyright Year	2011
Abstract	Background:It has been suggested that the relative importance of oestrogen-metabolising pathways may affect the risk of oestrogen-dependent tumours including endometrial cancer. One hypothesis is that the 2-hydroxy pathway is protective, whereas the 16α-hydroxy pathway is harmful.Methods:We conducted a case–control study nested within three prospective cohorts to assess whether the circulating 2-hydroxyestrone : 16α-hydroxyestrone (2-OHE1 : 16α-OHE1) ratio is inversely associated with endometrial cancer risk in postmenopausal women. A total of 179 cases and 336 controls, matching cases on cohort, age and date of blood donation, were included. Levels of 2-OHE1 and 16α-OHE1 were measured using a monoclonal antibody-based enzyme assay.Results:Endometrial cancer risk increased with increasing levels of both metabolites, with odds ratios in the top tertiles of 2.4 (95% CI=1.3, 4.6; Ptrend=0.007) for 2-OHE1 and 1.9 (95% CI=1.1, 3.5; Ptrend=0.03) for 16α-OHE1 in analyses adjusting for endometrial cancer risk factors. These associations were attenuated and no longer statistically significant after further adjustment for oestrone or oestradiol levels. No significant association was observed for the 2-OHE1 : 16α-OHE1 ratio.Conclusion:Our results do not support the hypothesis that greater metabolism of oestrogen via the 2-OH pathway, relative to the 16α-OH pathway, protects against endometrial cancer.
ISSN	00070920
Journal	British Journal of Cancer
Volume Number	105
PubMed Central reference number	PMC3241553
Issue Number	9
PubMed reference number	21952628
e-ISSN	15321827
DOI	10.1038/bjc.2011.381
Language	English
Publisher	Nature Publishing Group
Publisher Date	2011-09-27
Access Restriction	Open
Rights License	This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material.If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/. Copyright © 2011 Cancer Research UK
Subject Keyword	endometrial cancer nested case–control study oestrogen metabolites 2-hydroxyestrone 16α-hydroxyestrone, post-menopause
Content Type	Text
Resource Type	Article
Subject	Cancer Research Oncology