Immunosuppressive strategies that are mediated by tumor cells

Annu Rev Immunol. 2007;25:267-96. doi: 10.1146/annurev.immunol.25.022106.141609.

Abstract

Despite major advances in understanding the mechanisms leading to tumor immunity, a number of obstacles hinder the successful translation of mechanistic insights into effective tumor immunotherapy. Such obstacles include the ability of tumors to foster a tolerant microenvironment and the activation of a plethora of immunosuppressive mechanisms, which may act in concert to counteract effective immune responses. Here we discuss different strategies employed by tumors to thwart immune responses, including tumor-induced impairment of antigen presentation, the activation of negative costimulatory signals, and the elaboration of immunosuppressive factors. In addition, we underscore the influence of regulatory cell populations that may contribute to this immunosuppressive network; these include regulatory T cells, natural killer T cells, and distinct subsets of immature and mature dendritic cells. The current wealth of preclinical information promises a future scenario in which the synchronized blockade of immunosuppressive mechanisms may be effective in combination with other conventional strategies to overcome immunological tolerance and promote tumor regression.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Antigen Presentation / immunology
  • Dendritic Cells / immunology*
  • Dendritic Cells / pathology
  • Humans
  • Immune Tolerance*
  • Immunosuppressive Agents / immunology
  • Killer Cells, Natural / immunology*
  • Killer Cells, Natural / pathology
  • Neoplasms / immunology*
  • Neoplasms / pathology
  • Neoplasms / therapy
  • T-Lymphocytes, Regulatory / immunology*
  • T-Lymphocytes, Regulatory / pathology
  • Tumor Escape / immunology*

Substances

  • Immunosuppressive Agents