Tumor immunoediting and immunosculpting pathways to cancer progression

Abstract

Recent studies have suggested that a natural function of the immune system is to respond and destroy aberrant, dysfunctional cells by a process called immunosurveillance. These studies also suggest that the tumors that arise despite immunosurveillance have been immunosculpted by the immune system. The purported abilities of tumors to induce immune tolerance and suppression, the increased pathogenic behavior of the tumor cells following exposure to immune effectors and the loss of immunogenicity (i.e. immunoediting) often observed in advanced stage tumors could be the result of immunosculpting. In some cases, these immunosculpting features may be permanent and irreversible. However, in other cases, reversible epigenetic mechanisms may underlie the immune resistant tumor phenotype. Regardless, these immune-induced alterations could contribute to cancer pathogenesis. Understanding the mechanisms by which tumors evade immunity will be important for disease prevention and therapeutics.

Figure

Immunosurveillance: Unless the immune system can eradicate the dysfunctional cells or tissue, chronic immunosurveillance results in immunosculpting of which there are two outcomes, immune escape and aggression, which are mediated by two mechanisms, immunoediting and inflammation-induced tumor promotion, respectively. These two mechanisms interact to promote disease progression in cancer.