Table 2.

Projects in the Harvard University TREC Center (Principal Investigator: Frank B. Hu, MD, PhD)

Project 1: Sleep duration, energy balance, and insulin resistance in children Project Leader: Elsie M. Taveras, MD, MPH This project will investigate the role of sleep duration and sleep patterns in early childhood as novel risk factors for obesity and markers of adipose tissue and metabolic dysfunction in adolescence, using data from Project Viva, a prospective pre-birth cohort study (birth to age 12 years). The specific aims are: 1) to examine the extent to which short sleep duration in infancy, chronic insufficient sleep from infancy to mid-childhood, and sleep duration and efficiency at age 12 years are associated with adiposity and cancer-related biomarkers; 2) to examine the extent to which these associations are mediated by dietary behaviors, the composition of diet, and physical activity/inactivity behaviors (e.g., television viewing); and 3) to examine the extent to which these associations are modified by genetic factors.

Project 2: Environmental and lifestyle factors, obesity and cancer-related biomarkers Project Leader: Frank Hu, MD, PhD This project will examine the association of behavioral and environmental factors with circulating levels of cancer-related biomarkers among 750 middle aged women in the Nurses’ Health Study, and will evaluate whether selected genetic characteristics modify the associations between behavioral and environmental factors and risk of obesity. The aims that will be specifically addressed in this project are: 1) to examine associations between energetic factors and cancer-related biomarkers (insulin/IGF pathway, adipokines, and sex hormones); 2) to examine the relationships of neighborhood social economical status (SES) and built environment (assessed by the county sprawl index) with cancer-related biomarkers; and 3) to examine whether genetic factors modify the associations between behavioral and structural factors and risk of obesity and long-term weight gain.

Project 3: Energetics, fatal prostate cancer, and overall survival. Project Leaders: Jing Ma, MD, PhD and Howard Sesso, ScD The overall goal of this project is to gain a better understanding of the biological mechanisms linking obesity with prostate cancer survival, with a focus on biomarkers of the insulin/IGF pathway and adipocyte function. This project will investigate how geospatial and genetic variables are related to biomarker levels and prostate cancer survival in the Physicians’ Health Study, allowing for thematic continuity across projects. The findings of these studies will provide new insights into the role of energy metabolism in prostate cancer progression, will guide the identification of novel cancer therapeutic targets, and will help the development of cancer prevention strategies spanning urban planning, diet, and lifestyle modification.

Project 4: The impact of exercise and metformin on hyperinsulinemia in colorectal cancer survivors. Project Leaders: Jeffrey Meyerhardt, MD, MPH, Jennifer Ligibel, MD and Lee W. Jones, PhD The primary goal of this project is to determine changes in fasting insulin levels after 6 months of either supervised exercise training alone, metformin alone, or a combination of the two interventions in stage I-III colorectal cancer survivors. The study design is a 2 × 2 randomized trial of supervised aerobic exercise guided by validated behavioral support techniques versus attention control and metformin versus placebo. This trial will provide data that will be very useful in designing large-scale trials to explore the impact of these interventions upon colorectal cancer recurrence and survival.