The immune response to tumors.

The immune response to tumors is complex. Cells of the immune system can inhibit tumor growth and progression through the recognition and rejection of malignant cells, a process referred to as immunoediting. Yet, immune responses can also promote tumor cell growth, survival, and angiogenesis through the induction of oncogenic inflammation. Immunodeficiency can predispose to the development of spontaneous and virally induced cancer, and established tumors often generate immunosuppressive microenvironments that can block productive antitumor immunity, serving as a substantial barrier to effective immune therapy. Through a deeper understanding of the complicated relationship between tumors and the immune system, tumor immunology strives to harness the immune system to generate protective antitumor responses in patients. Copyright 2009 by John Wiley & Sons, Inc.