Re-education of tumor-associated macrophages by CXCR2 blockade drives senescence and tumor inhibition in advanced prostate cancer

Tumor-associated macrophages (TAMs) represent a major component of the tumor microenvironment that supports tumorigenesis. Here we found that prostate tumors are strongly infiltrated by TAMs expressing the C-X-C chemokine receptor type 2 (CXCR2). Pharmacological blockade of the CXCR2 receptor by a selective antagonist promoted the re-education of TAMs towards a pro-inflammatory phenotype. In vitro gene expression profiling revealed that CXCL2 promotes a pro-tumorigenic (M2-like) functional state in macrophages. In vitro gene expression profiling of macrophagesand sorted CD45+ negative epithelial cells