CD44 and neoplasm: To study the tumor-specific accumulation of CD44-IR700, we carried out NIR fluorescence imaging of nude mice bearing bilateral tumors (in the images MDA-MB-231 is the upper tumor and BT474 is the lower tumor) before and after intravenous (i.v.) injection of 50 μg of CD44-IR700 or IgG-IR700 or 1 nmol of IR700 (n = 4 per group).