M J Reed, R W Cheng, P A Beranek, and V H T James
C Palmieri, G J Cheng, S Saji, M Zelada-Hedman, A W√§rri, Z Weihua, S Van Noorden, T Wahlstrom, R C Coombes, M Warner, and J-A Gustafsson
Estrogen is essential for normal growth and differentiation in the mammary gland. It also supports growth of approximately 50% of primary breast cancers. For this reason, removal of estrogen or blocking of its action with the anti-estrogen, tamoxifen, is the main treatment for estrogen receptor alpha (ERalpha)-positive tumors. In 1996, when oncologists became aware of a second ER, ERbeta, there was some doubt as to whether this receptor would be of importance in breast cancer because the clinical consensus was that responsiveness to tamoxifen is related to the presence of ERalpha in breast cancer. Today we know that ERalpha and ERbeta have distinct cellular distributions, regulate separate sets of genes and can oppose each other's actions on some genes. We also know that ERbeta is widely expressed in both the normal and malignant breast and that there are proliferating cells in the breast which express ERbeta. In this review we summarize what is known about ERbeta in breast cancer and examine the possibility that ERbeta-selective ligands may well represent a useful class of pharmacological tools with a novel target, namely proliferating cells expressing ERbeta.
Deborah J Thompson, Tracy A O'Mara, Dylan M Glubb, Jodie N Painter, Timothy Cheng, Elizabeth Folkerd, Deborah Doody, Joe Dennis, Penelope M Webb, for the Australian National Endometrial Cancer Study Group (ANECS), Maggie Gorman, Lynn Martin, Shirley Hodgson, for the National Study of Endometrial Cancer Genetics Group (NSECG), Kyriaki Michailidou, Jonathan P Tyrer, Mel J Maranian, Per Hall, Kamila Czene, Hatef Darabi, Jingmei Li, Peter A Fasching, Alexander Hein, Matthias W Beckmann, Arif B Ekici, Thilo Dörk, Peter Hillemanns, Matthias Dürst, Ingo Runnebaum, Hui Zhao, Jeroen Depreeuw, Stefanie Schrauwen, Frederic Amant, Ellen L Goode, Brooke L Fridley, Sean C Dowdy, Stacey J Winham, Helga B Salvesen, Jone Trovik, Tormund S Njolstad, Henrica M J Werner, Katie Ashton, Tony Proietto, Geoffrey Otton, Luis Carvajal-Carmona, Emma Tham, Tao Liu, Miriam Mints, for RENDOCAS, Rodney J Scott, Mark McEvoy, John Attia, Elizabeth G Holliday, Grant W Montgomery, Nicholas G Martin, Dale R Nyholt, Anjali K Henders, John L Hopper, Nadia Traficante, for the AOCS Group, Matthias Ruebner, Anthony J Swerdlow, Barbara Burwinkel, Hermann Brenner, Alfons Meindl, Hiltrud Brauch, Annika Lindblom, Diether Lambrechts, Jenny Chang-Claude, Fergus J Couch, Graham G Giles, Vessela N Kristensen, Angela Cox, Manjeet K Bolla, Qin Wang, Stig E Bojesen, Mitul Shah, Robert Luben, Kay-Tee Khaw, Paul D P Pharoah, Alison M Dunning, Ian Tomlinson, Mitch Dowsett, Douglas F Easton, and Amanda B Spurdle
Candidate gene studies have reported CYP19A1 variants to be associated with endometrial cancer and with estradiol (E2) concentrations. We analyzed 2937 single nucleotide polymorphisms (SNPs) in 6608 endometrial cancer cases and 37 925 controls and report the first genome wide-significant association between endometrial cancer and a CYP19A1 SNP (rs727479 in intron 2, P=4.8×10−11). SNP rs727479 was also among those most strongly associated with circulating E2 concentrations in 2767 post-menopausal controls (P=7.4×10−8). The observed endometrial cancer odds ratio per rs727479 A-allele (1.15, CI=1.11–1.21) is compatible with that predicted by the observed effect on E2 concentrations (1.09, CI=1.03–1.21), consistent with the hypothesis that endometrial cancer risk is driven by E2. From 28 candidate-causal SNPs, 12 co-located with three putative gene-regulatory elements and their risk alleles associated with higher CYP19A1 expression in bioinformatical analyses. For both phenotypes, the associations with rs727479 were stronger among women with a higher BMI (P interaction=0.034 and 0.066 respectively), suggesting a biologically plausible gene-environment interaction.