Dr. Heidi DiFrancesca
I have always been fascinated by science, in particular Biology. But my interested deepened when I began taking upper level Cell and Molecular, Physiology, and Biochemistry courses during my undergraduate academic career at a small Christian university in Tennessee.
I was not certain of whether I wanted to go to medical school or graduate school upon graduation. So, I took some time off from school, got married, and a couple of years later decided that graduate school was the route for me. Because I had taken some off, I chose to study at a medium-sized research institution, Duquesne University in Pittsburgh, PA. For me, it was important to have more personalized attention that I might not have gotten at a larger research institution.
At Duquesne, I chose to join a lab that was doing research in breast cancer. I find the disruption of the normal function of cellular systems and the etiology of cancers absolutely
My research was focused on the enzyme steroid sulfatase and its potential use as a prognostic indicator of hormone-dependent breast cancers. Based on my research and other studies done in the lab at Duquesne, steroid sulfatase does appear to have a prognostic value in hormone-dependent breast cancers. Preliminary evidence suggests that there is a correlation between high levels of this enzyme and more aggressive hormone-dependent cancers.
I am a member of the American Association for Cancer Research (AACR) and the Society for the Study of Reproduction (SSR). I was also a participant in AACR’s Women in Science program.
Prior to joining the University of Mary Harden-Baylor faculty, I took a teaching sabbatical to care for my daughter, who was born very sick. Before this, I served as associate professor at McMurry University in Abilene, TX, where I taught Genetics, Cell and Molecular Biology, and Cancer Biology. I had several students involved in independent research projects centered on steroid sulfatase in breast cancers. I also collaborated with a small, local biotechnology company and Texas Tech University's Pharmacy School for a couple of the student projects being done in my lab.
Outside of the University, I am an active member of our local church, which is affiliated with the International Fellowship of Christian Assemblies. I also actively work with my husband in ministry who is an ordained minister. In addition, I enjoy spending time with my husband and my daughter exploring the world around us.
I find the disruption of the normal function of cellular systems and the complex behavior of human cancers absolutely fascinating. To this end, I am interested in the molecular and cellular mechanisms that create cancer. Though we have been able gain valuable insight into cancer formation and progression, there are still major questions that remain murky and poorly resolved. Many of those questions revolve around the complex signaling molecules that operate inside our cells, most of which are involved in intricate signaling circuitry that operate to make the life-and-death decisions that determine the fate of individual cells within our body. Those decisions ultimately determine whether or not one of our cells will begin a journey down the long road leading to cancerous proliferation and finally to a life threatening tumor.
Consequently, my primary research interests include physiological, cellular, and molecular influences on the development of cancer, in particular endocrine cancers such as breast cancer. The endocrine system, more specifically steroid hormones, often plays key roles in cancer growth, which is often dependent on the bioavailability of these molecules. My research is focused on the enzyme steroid sulfatase and its potential use as a prognostic indicator of hormone-dependent breast cancers. Steroid sulfatase is an enzyme that converts inactive estrogens into active estrogens. Estrogens are important signaling molecules that signal cell growth. As a result, estrogens have the ability to greatly impact the growth of human endocrine tumors. Based on my research and previous studies, steroid sulfatase does appear to have a prognostic value in hormone-dependent breast cancers, and that there is a relationship between high levels of this enzyme and more aggressive hormone-dependent breast cancers, as well as other endocrine cancers like prostate cancer.
I would like to continue research in the fields of cancer biology and endocrinology. While I am not limited to specific cancers, I am highly interested in hormone-dependent cancers such as breast, ovarian, endometrial, and prostrate.
Publications and Presentations
- Selcer, KW, DiFrancesca, HM, Chandra, AB, Li, PK.
Immunohistochemical Analysis of Steroid Sulfatase in Human Tissues.
Journal of Steroid Biochemistry and
Molecular Biology. 2007 105(1-5):115-123.
- “Characterization of the Enzyme Steroid Sulfatase in MC-3T3 E1 Mouse Bone Cells.” DiFrancesca HM, Selcer KW. Society for the Study Reproduction, San Antonio, TX, July 2007
- “Regulation of Steroid Sulfatase in Human Breast Cancer Cells and Mouse Bone Cells.” DiFrancesca,HM. Ph.D. Candidate Seminar, Duquesne University October, 2006