Lewis A. Chodosh, MD, PhD

2008-2009 BCRF Project:
Women who give birth to their first child at a young age have a substantially reduced risk of breast cancer compared to women who never have children or who have their first child later in life. In addition, while childbirth at a young age reduces a woman's risk of breast cancer, pregnancy by itself is associated with a transient increased risk of the disease for 10 to 15 years following childbirth.

With BCRF support, Dr. Chodosh and his team of researchers are developing laboratory models to investigate the complex effects of pregnancy and childbirth on breast cancer risk. Their goal is to understand these effects at a molecular and a cellular level with the ultimate hope of learning how to mimic the natural protective biological effects of pregnancy. Over the past year, Dr. Chodosh and his colleagues have made progress in understanding the basis for the protective effect of pregnancy on breast cancer risk. In particular, the Chodosh laboratory has demonstrated that pregnancy-induced protection against breast cancer is widely conserved evolutionarily and has defined a molecular signature. The Chodosh laboratory has also made progress in understanding how pregnancy can also increase women's risk of breast cancer.

Together, these observations provide new insights into potential mechanisms by which pregnancy can alter breast cancer risk. In the coming year, BCRF will support the investigators as they continue to seek to understand the molecular basis of pregnancy-induced changes in breast cancer risk, which include short-term increases in risk for estrogen receptor-negative breast cancer as well as long-term decreases in risk for estrogen receptor-positive breast cancer. These studies take advantage of innovative models for reproductive endocrine risk factors for breast cancer generated, in part, with BCRF support.

Bio:
Dr. Lewis Chodosh joined the faculty of the University of Pennsylvania School of Medicine in 1994 and currently serves as Vice Chairman of the Department of Cancer Biology. Dr. Chodosh holds appointments as an Associate Professor with Tenure in the Departments of Cancer Biology, Cell & Developmental Biology, and Medicine in the Division of Endocrinology, Diabetes and Metabolism. In addition, Dr. Chodosh is an Associate Investigator of the Abramson Family Cancer Research Institute. As a physician-scientist, Dr. Chodosh is principally dedicated to leading a research laboratory of 23 graduate students, technologists and postdoctoral fellows in a comprehensive research program aimed at eradicating breast cancer.

Dr. Chodosh's scientific career is founded on academic achievement. He graduated summa cum laude, Phi Beta Kappa from Yale University in 1981 with Distinction in Molecular Biophysics and Biochemistry. In 1989, Dr. Chodosh simultaneously received his M.D. from Harvard Medical School, where he graduated magna cum laude, and his Ph.D. in Biochemistry at the Massachusetts Institute of Technology under the mentorship of Nobel laureate, Dr. Phillip Sharp. After a residency program in Internal Medicine at the Massachusetts General Hospital, Dr. Chodosh completed a clinical fellowship in Endocrinology at the Massachusetts General Hospital in 1992 and a postdoctoral research fellowship with Dr. Philip Leder at Harvard Medical School in 1994.

As a clinical and scientific trainee, Dr. Chodosh has received numerous honors including the Leon Reznick Memorial Prize for Excellence in Research from Harvard Medical School, the Emerson Tuttle Cup for Distinguished Academic Achievement from Yale University, the Cornell Ingenuity in Mathematics and Science Award, the Harvard Book Prize, the Bausch and Lomb Honorary Science Award, the Merck Research Laboratories MD/PhD Fellowship, the Charles E. Culpeper Foundation Scholarship in Medical Science, and the AACR-Sidney Kimmel Cancer Symposium for Cancer Research Scholar Award. Dr. Chodosh was elected to the American Society for Clinical Investigation in 2002.

As an independent investigator at the University of Pennsylvania, Dr. Chodosh has focused his clinical and research training on developing new experimental approaches to understanding, treating and preventing breast cancer. Dr. Chodosh is particularly interested in identifying the mechanisms by which human cancers become resistant to therapy, as well as in understanding how normal events in a woman's life can be protective against breast cancer. In pursuit of these goals, Dr. Chodosh's laboratory has developed several novel genetically engineered mouse models for breast cancer, as well as a number of innovative approaches to analyzing large microarray gene expression profiling data sets.

In addition, Dr. Chodosh serves as an Attending Physician on the Endocrine Consult Service at Hospital of the University of Pennsylvania. Dr. Chodosh also serves as an advisor to the Harvard Nurses Health Study, is an editor of the scientific journals Breast Cancer Research and Cancer Biology and Treatment, and is on the Editorial Board of the Journal of Mammary Biology and Neoplasia.