Impact of a pre-operative exercise intervention on breast cancer proliferation and gene expression: Results from the Pre-Operative Health and Body (PreHAB) Study

Purpose: Exerciseafter breast cancer diagnosis is associated with lower cancer-specific mortality, but the biological mechanisms through which exerciseimpacts breast cancer are not fully understood. The Pre-Operative Health and Body (PreHAB) Study was a randomized windowof opportunitytrial designed to test the impact of exerciseon Ki-67, gene expression, and other biomarkers in women with breast cancer. Experimental Design: Inactive women with newly diagnosed breast cancer were randomized to an exerciseintervention or mind-body control group, and participated in the study between enrollment and surgery (mean 29.3 days). Tumor and serum were collected at baseline and surgery. Results: Forty-nine women were randomized (27 exercise, 22 control). At baseline, mean age was 52.6, body mass index was 30.2kg/m2 and exercisewas 49 min/wk. Exerciseparticipants significantly increased exercisevs. controls (203 vs. 23 min/week, p