An innovative single-domain antibody that bispecifically binds and neutralizes CCL2 and CCL5 (BisCCL2/5i) with high potency and specificity reverses the immunosuppressive process by which CCL2 and CCL5 attract Tumor-associated macrophages (TAMs) to infiltrate and induce their polarization toward the pro-tumor M2 phenotype. This evidence concerns the gene CCL5 and neoplasm.