TGFB1 and metastatic neoplasm: The prominent immunosuppressive TGF-β cytokine within the TME has been reported to induce a population of TANs with a pro-tumor N2 phenotype, suppressing the cytotoxicity of neutrophils and restricting their entry into the tumor.335,704 TGF-β is abundant both at primary and metastatic tumors, and neutrophil cytotoxicity is not evident in these sites, whereas the pro-tumor functions are manifested.