CCL5 and/or CCR5 overexpression has been found in many tumors, including acute lymphocytic leukemia [39], Hodgkin lymphoma [38,40], multiple myeloma [41,42], breast cancer [37,43], colorectal carcinoma [44,45], esophageal cancer [46], gastric adenocarcinoma [47,48], head and neck cancer [49], melanoma [50], pancreatic cancer [51], and prostate cancer [52]. Here, CCL5 is linked to breast cancer.