Mechanisms of Tumor Escape from the Immune Response

The progressive growth of a malignant tumor is accompanied by a decline in the immune response, through mechanisms that have, until recently, been poorly understood. The new era of biological therapies, including cytokines, adoptive transfer of TIL cells, gene therapy and others, brought forth the need to understand the impact of the tumor on the immune system. Moreover, the inability to achieve in humans the unequivocal success of immunotherapy in murine models suggests the possibility that cancer can impair the development of a therapeutic immune response. Scientific and technological advances in cellular and molecular biology during the last two decades have provided new tools with which to explore the dysfunctional immune system of patients with cancer. Novel immunology concepts have provided new insights into changes occurring in tumor cells and the immune system, providing a more cohesive understanding of the process, including: *diminished or absent expression of HLA antigens and co-stimulatory molecules *arrested maturation of dentritic cells *alterations in expression of some signal transduction proteins *increased apoptosis in T and NK cells *presence of suppressor CD+4 and CD25+ T cells Mechanisms of Tumor Escape from the Immune Response provides an introduction to this rapidly developing and, as yet, unsettled area of cancer research, and will be a valuable reference for clinicians and researchers working in the field of cancer immunotherapy.