ABSTRACT
INTRODUCTION Immunotherapy is based on the concept of using the body’s own immune system to fi ght disease. Cancer vaccines are a form of active immunotherapy with the goal to generate an endogenous and specifi c immune response to tumor antigens or tumor-associated antigens (TAAs) that can target and destroy cancer cells. Current vaccine strategies aim to induce not only a very robust and effective CD8 + cytotoxic T-cell response but also CD4 + T helper responses, B-cell responses, and natural killer (NK) cell activity. There are many ongoing phase III cancer vaccine trials nearing completion, and some of these are showing promise, an indication that cancer immunotherapy is here to stay. In 2010, sipuleucel-T (Provenge™, Dendreon Corporation, Seattle, WA), an autologous antigen-presenting cell-(APC) enriched vaccine preparation loaded with a prostatic acid phosphatase (PAP)–granulocyte-macrophage colony-stimulating factor (GM-CSF) fusion protein, was the fi rst immunotherapy vaccine approved by the Food and Drug Administration for treatment of castration-resistant metastatic prostate cancer. As such, the future of immunotherapy will continue to evolve as these clinical trials shed light on tumor-specifi c immune mechanisms and will, without doubt, involve a multi-pronged approach that can translate to effective cancer vaccine therapies that have a sustained clinical benefi t.
