Tricks tumors use to escape from immune control

Tumor escape from the host immune system has been a major problem in immunotherapy of human malignancies. Human tumors are known to develop escape strategies, which might differ among tumors of the same histology. This suggests that host-tumor interactions create the tumor microenvironment that is unique for every tumor. Recent advances in cancer immunology allow for a better understanding of the mechanisms tumors use to execute immune escape and of the relationship the tumor establishes with immune cells. It is now feasible to obtain an immune signature of the tumor, that is to define the genetic, molecular and functional profiles of immune cells in the tumor microenvironment. This knowledge might be critically important for the personalized selection of available therapies and thus for clinical outcome. (C) 2009 Elsevier Ltd. All rights reserved.