This is a competing renewal application of a MERIT award currently in its 36th year of funding. The long-term objectives of these studies have been to elucidate the mechanisms by which systemic hormones and local growth factors regulate the normal development of the mammary gland, and to determine how these regulatory mechanisms have deviated in breast cancer. More than a decade ago our laboratory and others presented evidence that steroid hormone-induced proliferation of mammary ductal epithelial cells was regulated by paracrine mechanisms. Recent studies have indicated that steroid hormone regulation of mammary stem and progenitor cells in both the normal mammary gland and luminal breast cancers is also mediated by local paracrine mechanisms involving Wnts, fibroblast growth factors and Rank ligand. Our current studies combine gain- and loss-of function mouse genetic experiments using transgenic, conditional knockout, and lentivirally-transduced mammary epithelial cells and transplantation into the cleared mammary fat pad with the in situ analysis of signal transduction pathways. They will continue to focus on the understanding of both paracrine, juxtacrine and autocrine mechanisms of cell fate determination in the murine mammary gland with emphasis on the mechanisms regulating stem/progenitor cell self-renewal, normal ductal morphogenesis, and early progression in breast cancer. To accomplish these goals we propose: 1. To elucidate the role of the canonical and non-canonical Wnt pathways in mammary stem/progenitor cell self-renewal and survival. 2. To elucidate the molecular mechanisms of FGFR 1 and FGFR2 action on mammary stem and progenitor cells. 3. To understand the mechanisms of Wnt and Fgf pathway cooperativity in mammary stem/progenitor self- renewal and how these are altered in breast cancer. 4. To delineate the role of specific C/EBPss protein isoforms in both stem cell self-renewal and luminal/alveolar cell fate determination 5. To elucidate the role of noncoding RNAs(ncRNAs) in mammary gland development and breast cancer. """"""""Our understanding of the biology and developmental genetics of the normal mammary gland is a barrier to progress...a more complete understanding of the normal mammary gland at each stage of development....will be a critical underpinning of continued advances in detecting, preventing and treating breast cancer""""""""

Public Health Relevance

Approximately 1 in 8 women will be stricken by breast cancer in their lifetime. Discovering the mechanisms by which hormones regulate normal mammary stem and progenitor cells will be critical to our understanding of the alterations which occur both during both the initiation of breast cancer, as well as during cancer metastasis and disease recurrence.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA016303-39
Application #
8676655
Study Section
Molecular and Cellular Endocrinology Study Section (MCE)
Program Officer
Sathyamoorthy, Neeraja
Project Start
1978-08-01
Project End
2017-05-31
Budget Start
2014-06-01
Budget End
2015-05-31
Support Year
39
Fiscal Year
2014
Total Cost
Indirect Cost
Name
Baylor College of Medicine
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
City
Houston
State
TX
Country
United States
Zip Code
77030
Sreekumar, Amulya; Toneff, Michael J; Toh, Eajer et al. (2017) WNT-Mediated Regulation of FOXO1 Constitutes a Critical Axis Maintaining Pubertal Mammary Stem Cell Homeostasis. Dev Cell 43:436-448.e6
Welte, Thomas; Zhang, Xiang H-F; Rosen, Jeffrey M (2017) Repurposing Antiestrogens for Tumor Immunotherapy. Cancer Discov 7:17-19
Zhang, Peng; He, Dandan; Xu, Yi et al. (2017) Genome-wide identification and differential analysis of translational initiation. Nat Commun 8:1749
Roarty, K; Pfefferle, A D; Creighton, C J et al. (2017) Ror2-mediated alternative Wnt signaling regulates cell fate and adhesion during mammary tumor progression. Oncogene 36:5958-5968
Shore, Amy N; Chang, Chi-Hsuan; Kwon, Oh-Joon et al. (2016) PTEN is required to maintain luminal epithelial homeostasis and integrity in the adult mammary gland. Dev Biol 409:202-17
Welte, Thomas; Kim, Ik Sun; Tian, Lin et al. (2016) Oncogenic mTOR signalling recruits myeloid-derived suppressor cells to promote tumour initiation. Nat Cell Biol 18:632-44
Roarty, Kevin; Shore, Amy N; Creighton, Chad J et al. (2015) Ror2 regulates branching, differentiation, and actin-cytoskeletal dynamics within the mammary epithelium. J Cell Biol 208:351-66
Zhang, Mei; Rosen, Jeffrey M (2015) Developmental Insights into Breast Cancer Intratumoral Heterogeneity. Trends Cancer 1:242-251
Holdman, Xue B; Welte, Thomas; Rajapakshe, Kimal et al. (2015) Upregulation of EGFR signaling is correlated with tumor stroma remodeling and tumor recurrence in FGFR1-driven breast cancer. Breast Cancer Res 17:141
Zhang, Mei; Tsimelzon, Anna; Chang, Chi-Hsuan et al. (2015) Intratumoral heterogeneity in a Trp53-null mouse model of human breast cancer. Cancer Discov 5:520-33

Showing the most recent 10 out of 105 publications