Future directions for immunotherapeutic intervention against sarcomas.

To discuss advances in immunotherapy as pertaining to systemic therapy for sarcomas. Developments in immunology will have direct relevance to studies in sarcomas and other cancers in the near future. Vaccines employing peptides are the backbone of many studies today due to issues of cost and ease of production, but intact or transfected whole tumor cells or antigen-pulsed or transfected dendritic cells are now being investigated as the immunogenic principle in sarcomas and other cancers. The importance of dendritic cells in generating immune responses is better appreciated than ever, as is the role of CD4+ CD25+ regulatory T cells in mediating immune responses. Enhancing costimulatory signals to T cells using anti-CD152 (CTLA4) and other antibodies or expanding anti-tumor cytotoxic T lymphocytes ex vivo are other means to enhance immunity to sarcoma-specific antigens. As of 2006, few studies are examining the utility of immunotherapy in sarcomas. However, a detailed understanding of the remarkable mechanics of how an immune response is mounted and how T cell activation and/or proliferation can be halted by the tumor will be central to properly design new studies of immunological agents against sarcomas and other cancers.