Bioluminescence imaging of primary tumor, metastatic growth and CTC dynamics in the 4T1-F3 orthotopic mammary tumor model.

<p>(<b>A</b>) Primary tumor growth in the mammary fat pad (m.f.p) as monitored using Bioluminescence (BLI) imaging, following implantation of 5×10⁶ 4T1-F3 cells in the fourth left mammary fat pad (image scales in p/s/cm²/sr), and (<b>B</b>) Corresponding quantification of BLI signal in the m.f.p area, shown as mean ± SEM and fit of the mean values to an exponential tumor growth equation (dashed line, R² = 0.99). (<b>C</b>) Metastases in the upper body (lung area) as monitored using BLI in the same animals (image scales in p/s/cm²/sr) and (<b>D</b>) Corresponding quantification of the signal in the lung area, shown as mean ± SEM. (<b>E</b>) Corresponding quantification of blood BLI signal in 1-mL terminal blood samples from n = 3–4 animals/day (image scales in p/s/cm²/sr), shown as mean ± SEM. The image on the right shows BLI signal from CTCs in n = 3 terminal blood samples on day 12, (image scales in p/s/cm²/sr) (<b>I</b>) Statistical analysis showing the onset of lung metastasis and blood CTCs over time in the n = 40 animals.