Jennifer K. Richer Assistant Professor Pathology Ph.D. Campus Box 8104 RC1-North, Room 5122 Department of Pathology Phone: 303-724-3735 Jennifer.Richer@UCHSC.edu

Research Interests:

The lab studies the role of the sex steroid hormones estrogen and progesterone and their receptors in breast and endometrial cancer. Recently, via molecular profiling of breast cancers from a clinical trial before and after hormone therapy, we have identified proteins associated with response or intrinsic resistance to hormone therapy. In responsive tumors we are investigating how certain proteins are involved in tumor regression achieved by hormone therapy. In tumors with de novo resistance, we study the mechanisms by which the tumor cells survive hormone therapy, despite being hormone receptor positive. We have identified active androgen receptors and a “lipogenic phenotype” as key characteristics of estrogen receptor positive breast tumors that are resistant to endocrine therapy. Endometrial cancer studies in the lab focus on a transcription factor, ZEB1, which while hormonally controlled in the normal endometrium and myometrium, becomes aberrantly expressed in aggressive Type II endometrial cancers. ZEB1 causes such tumors to become highly invasive by initiating an epithelial to mesenchymal transition. We are actively pursuing ways to control ZEB1 expression to render these aggressive tumors more treatable.

Selected Publications

Spoelstra, NS, Manning NG, Higashi Y, Darling D, Meenakshi S, Shroyer S, Broaddus RR, Horwitz KB, and JK Richer. The transcription factor ZEB1 is aberrantly expressed in aggressive uterine cancers.CANCER RESEARCH. 2006 66(7):3893-3902.

Harvell DM, Richer JK, Allred DC, Sartorius CA, Horwitz KB. Estradiol Regulates Different Genes in Human Breast Tumor Xenografts Compared to the Identical Cells in Culture. ENDOCRINOLOGY 147(2):700-13 2006

Jacobsen BM, Schittone SA, Richer JK and KB Horwitz. Progesterone-Independent Effects of Human Progesterone Receptors (PRs) in Estrogen Receptor-Positive Breast Cancer: PR Isoform-Specific Gene Regulation and Tumor Biology. MOL ENDOCRINOLOGY 19(3): 574-87. 2005

Richer, J.K , Jacobson, B., Manning, N.G., and Horwitz, K.B. 2002. Functional differences between progesterone receptor isoforms: differential gene regulation in breast cancer cells. J Biol Chem 277: 5209-5218, 2002.

Jacobsen, B.M., Richer, J.K., Schittone, S.A. and Horwitz, K.B. 2002. New Human Breast Cancer Cells to Study Progesterone Receptor Isoform Ratio Effects and Ligand-independent Gene Regulation. J Biol Chem 277: 27793-27800, 2002.

Richer, J.K., Lange, C.A., Manning, N.G., Owen, G., Powell, R.L. and Horwitz, K.B. Convergence of Progesterone with Growth Factor and Cytokine Signaling in Breast Cancer: Progesterone Receptors Regulate Signal Transducers and Activators of Transcription Expression and Activity. J Biol Chem 273: 31317-31326, 1998.

Lange, C.A., Richer, J.K., and Horwitz, K.B. Convergence of Progesterone and Epidermal Growth Factor Signaling in Breast Cancer: Potentiation of Mitogen Activated Protein Kinase Pathways. J Biol Chem 273: 31308-31316, 1998.

Richer, J.K., Lange, C.A., Weirman, A.M., Brooks, K.M., Tung, L., Takimoto, G.S., and Horwitz, K.B. Novel Progesterone Receptor Variants Repress Transcription by Wild-Type Receptors. Breast Cancer Research and Treatment 48:231-241, 1998.

Latest Publications in PubMed