Fig. 1.

Study design. Three-week-old female MTB/TAN mice were weaned onto matched study diets consisting of 60% calories from fat (high-fat diet) or 10% calories from fat (low-fat diet). Doxycycline (0.03 mg/ml) was provided in drinking water beginning at age 6 weeks to induce human epidermal growth factor receptor 2 (HER2)-driven mammary tumors. Once primary tumors reached target volume (500 cm³), the HER2 oncogene was downregulated by doxycycline withdrawal to induce tumor regression. Mice were then observed twice weekly for recurrence