Tumor Associated Neutrophils: Friend or Foe?
Cet article passe en revue les travaux récents sur les mécanismes impliquant les neutrophiles associés aux tumeurs dans la biologie du cancer
Neutrophils play an established role in host defense and in killing invading microorganisms. Although neutrophils are traditionally considered in the context of their anti-bacterial functions, it is becoming increasingly clear that tumor-associated neutrophils (TAN) play a major role in cancer biology. Neutrophils make up a significant portion of the inflammatory cell infiltrate in many models of cancer. Like all other leukocytes, they move into tissues under the influence of specific chemokines, cytokines and cell adhesion molecules. The tumor microenvironment has been shown to be responsible for their recruitment in cancer. We have found that TAN are a distinct population of neutrophils, differing markedly in their transcriptomic profile from both naïve neutrophils and the granulocytic fraction of myeloid-derived suppressor cells (G-MDSC).Studies have demonstrated specific examples of tumor-mediated signals (such as transforming growth factor-β [TGFβ]) that induce the formation of a pro-tumorigenic (N2) phenotype capable of supporting tumor growth and suppressing the anti-tumor immune response. However, there are also studies showing that TAN can also have an anti-tumorigenic (N1) phenotype. Herein, we explore the literature on the different mechanisms of TAN-recruitment to tumors, the unique characteristics of TAN, and what shapes their pro- and/or anti-tumor effects.
http://carcin.oxfordjournals.org/content/early/2012/03/16/carcin.bgs123.abstract