CCL18 and breast cancer: Based on the finding that recombinant CCL-18 and VEGF cause a strong migratory and invasive response in our aggressive breast cancer cells, we removed each of these components from M2a conditioned media and supplemented cancer cells with either VEGF-depleted media (ΔVEGF), CCL-18-depleted media (ΔCCL-18), or both VEGF- and CCL-18-depleted conditioned media (ΔCCL-18/ΔVEGF).