A detailed understanding of interplay between genetics and epigenetics in the progression and hormone dependence of distinct breast cancer subtypes is critical to the development of new approaches to prevention and therapy. To address this problem we have begun to explore the epigenetic state of the normal mammary epithelial cells and of tumor cells. We have used cell surface markers and fluorescence? activated cell sorting of normal mammary cells from ostensibly normal women undergoing reduction mammoplasty to operationally define mature luminal, luminal progenitor and basal/mammary stem cell? enriched populations.
In Aim 1 we will test the hypothesis that estrogen receptor (ER) signaling in breast cancer recapitulates ER signaling found in luminal progenitors. An understanding of the ER-regulated program in normal luminal progenitors has important implications for both hormonal chemoprevention and for endocrine therapy. We have also begun to investigate the potential impact of BRCA1 and BRCA2 genotype on ER signaling and the epigenetic state of the normal mammary gland.
Aim 2 will test the hypothesis that BRCA1 and BRCA2 in addition to their well-documented roles in maintaining genomic integrity play important roles in determining mammary cell fate and that ER signaling influences these effects. In preliminary studies we have found that the genes aberrantly expressed by luminal progenitor cells derived from BRCA2 carriers shows a striking overlap with the gene expression program that we recently defined as playing an important role in the oncogenic function of the epigenetic regulator EZH2 in castration-resistant prostate cancer.
Aim 3 will address the hypothesis that EZH2 plays a necessary role'in normal mammary development and an oncogenic role in breast cancer. These three specific aims depend critically on the Pathology Core and the strength of the collaborations supported by this Program Project.

Public Health Relevance

Understanding how the function of the estrogen receptor is altered during breast cancer progression and the impact of BRCA1 and BRCA2 on normal mammary development will lead to improvements in hormonal chemoprevention and endocrine therapy. Validation of EZH2 as an oncogene in breast cancer will provide a potentially important new therapeutic target.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Program Projects (P01)
Project #
Application #
Study Section
Special Emphasis Panel (ZCA1-RPRB-J (O1))
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Whitehead Institute for Biomedical Research
United States
Zip Code
Xiao, Tengfei; Li, Wei; Wang, Xiaoqing et al. (2018) Estrogen-regulated feedback loop limits the efficacy of estrogen receptor-targeted breast cancer therapy. Proc Natl Acad Sci U S A 115:7869-7878
Zhang, Jinfang; Bu, Xia; Wang, Haizhen et al. (2018) Cyclin D-CDK4 kinase destabilizes PD-L1 via cullin 3-SPOP to control cancer immune surveillance. Nature 553:91-95
Li, Andrew G; Murphy, Elizabeth C; Culhane, Aedin C et al. (2018) BRCA1-IRIS promotes human tumor progression through PTEN blockade and HIF-1? activation. Proc Natl Acad Sci U S A 115:E9600-E9609
Wu, Yanming; Zhang, Zhao; Cenciarini, Mauro E et al. (2018) Tamoxifen Resistance in Breast Cancer Is Regulated by the EZH2-ER?-GREB1 Transcriptional Axis. Cancer Res 78:671-684
Witwicki, Robert M; Ekram, Muhammad B; Qiu, Xintao et al. (2018) TRPS1 Is a Lineage-Specific Transcriptional Dependency in Breast Cancer. Cell Rep 25:1255-1267.e5
Jeselsohn, Rinath; Bergholz, Johann S; Pun, Matthew et al. (2018) Allele-Specific Chromatin Recruitment and Therapeutic Vulnerabilities of ESR1 Activating Mutations. Cancer Cell 33:173-186.e5
Hinohara, Kunihiko; Wu, Hua-Jun; Vigneau, S├ębastien et al. (2018) KDM5 Histone Demethylase Activity Links Cellular Transcriptomic Heterogeneity to Therapeutic Resistance. Cancer Cell 34:939-953.e9
Wan, Lixin; Xu, Kexin; Wei, Yongkun et al. (2018) Phosphorylation of EZH2 by AMPK Suppresses PRC2 Methyltransferase Activity and Oncogenic Function. Mol Cell 69:279-291.e5
Dreijerink, Koen M A; Timmers, H T Marc; Brown, Myles (2017) Twenty years of menin: emerging opportunities for restoration of transcriptional regulation in MEN1. Endocr Relat Cancer 24:T135-T145
Rashidian, Mohammad; Ingram, Jessica R; Dougan, Michael et al. (2017) Predicting the response to CTLA-4 blockade by longitudinal noninvasive monitoring of CD8 T cells. J Exp Med 214:2243-2255

Showing the most recent 10 out of 136 publications