A trend of initial expansion of total number of macrophages and of anti-tumor M1 macrophages was observed on Day 3 post treatment of tumor bearing mice with 7.4 kBq 225Ac-anti-CCR8 in both CT26 (Figures 5A, B) and MC38 (Figures 5C, D) tumors. Here, CCR8 is linked to neoplasm.