CTLA4 and prostate cancer: From trials initiated in 2012, sipuleucel-T is involved in at least seven trials against prostate cancer, combining sipuleucel-T with: different regimens of radiotherapy (19); administration of monoclonal antibody against cytotoxic T lymphocyte-associated protein 4 (CTLA-4) (20); administration of recombinant human IL-7 (21); and injection of DNA-based anti-cancer vaccine together with GM-CSF (22).