Sagiv and collaborators identified in human cancer blood three different distinct populations of circulating neutrophils: “a heterogeneous subset of low-density neutrophils (LDNs) that is present transiently in self-resolving inflammation but accumulate in both tumor bearing mice and cancer patients, mature high-density neutrophils (HDNs) and immature myeloid-derived suppressor cells (MDSCs).” In tumor bearing mice, HDNs are capable of switching to a TGF-β-triggered LDNs phenotype with immunosuppressive properties, similar to those of MDSCs (56) (Figure 2). Here, TGFB1 is linked to cancer.