Figure 4. Effect of mouse orthotopic tissue co-engraftment on human BT474 tumor growth.

BT474 tumor spheroids expressing H2B-GFP were implanted directly onto the dorsal skin (sc) ( a and b) or with mouse mammary fat pad donor tissue (EO) ( c and d) and monitored by IVM. ( a and c) Fluorescence IVM images on the indicated days after implantation. ( b and d) Relative tumor growth curves. Tumor size was measured on indicated days based on total GFP fluorescence signal relative to day 1 as in Figure 1. Mice received human estrogen supplement in ( c and d) but not ( a and b). Scale bar = 500 μm. n = 3–4 mice for all experiments.