Obesity is now a well recognized risk factor for postmenopausal breast cancer. However, mechanisms of action for this relationship have yet to be identified. Initial focus was on elevated estrogen levels resulting from androgen conversion by aromotase in expanded adipose tissue mass. More recently adipokine, proteins directly synthesized and secreted from adipose tissue, have been implicated in in vitro studies to have the potential to influence human breast cancer cell proliferation, i.e., leptin stimulates and adiponectin decreases cell numbers. Interestingly circulating levels of these two adipokines are impacted differently by body weight status, i.e., leptin and adiponectin levels are positively correlated and negatively correlated respectively with body weight. Over the past 10 years we and others have attempted to understand the in vivo effects of these two proteins on mammary tumor development using transgenic and xenograft mouse models of breast cancer. The effects of obesity as well as calorie restriction on circulating levels of leptin and adiponectin have been evaluated as well as tissue levels of the adipokines and their receptors. Our most recent study is evaluating the effects of calorie restriction and metformin on mammary tumor development after obesity has been established.

Lunch: Noon–1:00 p.m. (faculty/staff only, registration required)

Poster Session highlighting cancer and/or obesity: 1:00-3:00 p.m. Stewart Center 311
Graduate and undergraduate student competition with cash awards