CCL18 and breast cancer: To further examine whether CCL18 contributed to angiogenesis in breast cancer, we evaluated the angiogenic effects of CCL18, which does not have a mouse homolog [26], in tumor xenografts derived from MDA-MB-231 (high metastatic potential) or BT-474 (low metastatic potential) breast cancer cells in the mammary fat pads of NOD/SCID mice.