Jacobsen is an Assistant Professor in the Department of Pathology, University
of Colorado Anschutz Medical Campus. She obtained her PhD from Indiana
University in Biochemistry and Molecular Biology where she identified
transcriptional mediators required for differentiation of myeloid cells. Dr.
Jacobsen completed a postdoctoral fellowship in breast cancer at the University
of Colorado Health Sciences Center where she examined steroid receptor mediated
gene expression. In 2003 Dr. Jacobsen joined the faculty in the Department of
Medicine of the University of Colorado where she investigated the role of
steroid receptors on chemotherapy response in breast cancer. Dr. Jacobsen
joined the Department of Pathology in 2013 where she continues her work on
steroid receptors and breast cancer. Dr. Jacobsen has served as a reviewer for
multiple peer reviewed journals and on grant review panels for the Department
of Defense Breast Cancer Research Program.
focuses on the biology of mucin secreting breast cancers. Breast tumors
containing mostly secreted mucin (>90%) are called mucinous breast cancers
and comprise anywhere from 2-4% of all breast tumors. However, the number of
breast tumors that secrete less mucin (<90% mucus) is unknown. We are
interested in the role secreted mucins play in regulating the biology of breast
tumors, specifically on the proliferation, therapy response, and metastatic
behavior of tumor cells. We have created two novel breast cancer cell lines
that secrete mucins and use these cells to model the biology of mucin secreting
breast cancers. We are also interested in how steroid hormones like estrogen
and progesterone regulate production and secretion of mucins. Our studies also
suggest that different subsets of genes are regulated by estrogen in these
tumors versus breast tumors that don’t secrete mucus. We are also interested in
how mucin secreting breast cancers interact with the microenvironment.
A second focus
of our research is to improve the effectiveness of chemotherapy in breast and
ovarian tumors. We have shown that breast tumors that contain progesterone
receptors (PR) are less responsive to chemotherapy than those that lack PR. We
examine the underlying mechanisms for chemotherapy resistance and are testing
new combinatorial therapies with novel drugs to improve chemosensitivity of PR+
- Jambal P, Badtke MM, Harrell JC, Borges VF, Post MD, Sollender GE, Spillman MA, Horwitz KB, Jacobsen BM. Estrogen switches pure mucinous breast cancer to invasive lobular carcinoma with mucinous features. Breast Cancer Res Treat. 2013 Jan;137(2):431-48. doi: 10.1007/s10549-012-2377-x. Epub 2012 Dec 18. PMID: 23247610
- Schlaepfer IR, Hitz C, Gijon MG, Bergman BB, Eckel RH, Jacobsen BM. Progestin modulates the lipid profile and sensitivity of breast cancer cells to docetaxel. Mol Cell Endocrinol. 2012 Nov 5;363(1-2):111-21. doi: 10.1016/j.mce.2012.08.005. Epub 2012 Aug 16. PMID: 22922095
- Cittelly DM, Finlay-Schultz J, Howe EN, Spoelstra NS, Axlund SD, Hendricks P, Jacobsen BM, Sartorius CA, Richer JK. Progestin suppression of miR-29 potentiates dedifferentiation of breast cancer cells via KLF4. Oncogene. 2012 Jul 2. doi: 10.1038/onc.2012.275. [Epub ahead of print] PMID: 22751119
- Cochrane DR*, Jacobsen BM*, Howe EN, Connaghan K, Bain DL, and Richer JK Progestin regulated miRNAs that mediate progesterone receptor action in breast cancer Mol Cell Endocrinol. 2012 May 15;355(1):15-24. Epub 2012 Jan 18. PMID: 22330642 *co-first authors
- Jacobsen BM, Horwitz KB. Progesterone receptors, their isoforms and progesterone regulated transcription. 2012 Jun 24;357(1-2):18-29. Epub 2011 Sep 17. PMID: 21952082
- Badtke MM, Jambal P, Dye WW, Spillman MA, Post MD, Horwitz KB, Jacobsen BM. Unliganded progesterone receptors attenuate taxane-induced breast cancer cell death by modulating the spindle assembly checkpoint. Breast Cancer Res Treat. 2012 Jan;131(1):75-87. Epub 2011 Feb 22. PMID: 21340479
- Jacobsen BM, Jambal P, Schittone SA and Horwitz KB (2009) ALU-like repeats in promoters are position dependent co-response elements (coRE) that enhance or repress transcription by dimeric and monomeric progesterone receptors. Mol Endocrinology 2009 Apr 16. Jul;23(7):989-1000. Epub 2009 Apr 16.
- Jacobsen BM, Harrell JC, Jedlicka P, Borges VF, Varella-Garcia M and Horwitz KB (2006) Spontaneous fusion and transformation of mouse stroma by, malignant human breast cancer epithelium. Cancer Research 66(16): 8274-9.
- Ghatge RP, Jacobsen BM, Schittone SA, and Horwitz KB (2005) The progestational and androgenic properties of medroxyprogesterone acetate: gene regulatory overlap with dihydrotestosterone in breast cancer cells. Breast Cancer Res. 2005;7(6):R1036-50. Epub 2005 Nov 2.
- Jacobsen BM, Schittone SA, Richer JK, and Horwitz KB (2005) Progesterone Independent Effects of Human Progesterone Receptors (PR) in Estrogen Receptor Positive Breast Cancer: PR isoform-specific Gene Regulation and Tumor Biology. Mol Endocrinology 19(3):574-587.