Further studies are ongoing to determine the role of anti-CTLA-4 in prostate cancer immunotherapy, possibly as

an adjunct to other vaccine-based modalities. Conclusions Immunolearn more therapy for prostate cancer has made great strides. Ongoing clinical trials provide promise for the introduction of immunotherapy into the armamentarium Inhibitors,research,lifescience,medical against prostate cancer, but the precise role for immunotherapy remains to be determined. Combination of immunotherapies may be needed to improve the response rates and the duration of response. Investigators have begun to examine the effect of immunotherapy in combination with other standard treatment, including as an adjuvant to chemotherapy or radiotherapy and as a neoadjuvant

agent before prostatectomy. Although many studies examine efficacy in men with metastatic HRPC, there is mounting evidence for improved responses at earlier stages Inhibitors,research,lifescience,medical of disease: the ability of the tumor to evade the immune system may be lessened with lower tumor burden, or the immune system may already be weakened in men with later stages of disease. With mounting evidence of the impact of immune therapy upon prostate cancer, including modest survival benefits, the field remains Inhibitors,research,lifescience,medical an active area of investigation for therapy. Main Points In prostate cancer, effective immune strategies have been investigated for 25 years, and recent progress has been made in a variety of agents. Immunotherapy regimens Inhibitors,research,lifescience,medical under investigation include immunomodulatory cytokines/effectors, peptide and cellular immunization, viral vaccines, dendritic cell vaccines, and antibody therapies. A variety of studies have examined methods to stimulate the immune system to augment the immune reaction to prostate cancer; recent

strategies use immunomodulatory agents (granulocyte-macrophage colony-stimulating factor, Flt3 ligand, and IL-2) to stimulate antitumor response. Vaccine-based therapies often utilize prostate-specific (prostate-specific antigen, prostatic acid phosphatase, Inhibitors,research,lifescience,medical prostate-specific membrane antigen, prostate stem Mephenoxalone cell antigen) or tumor-specific antigens to direct the response. Gene therapy has merged with immunotherapy to induce immunoreactivity and antitumoral response in patients with prostate cancer. The approaches used in this merger have included both DNA and viral vaccines, and often immunomodulatory agents have been added to amplify the response. Numerous experimental immunologic regimens have adopted dendritic cells as the basis of their protocol. Sipuleucel-T is one of the most extensively studied dendritic cell modalities. Antibodies can be used to induce cellular cytotoxicity—in which the antibody directs lysis of tumor cells by macrophages and neutrophils—or they can be conjugated to deliver toxins or radioactive substances that result in cell death.