CD80 and Familial prostate cancer: This phenomenon has been observed among patients treated with PROSTVAC, which is a prostate cancer vaccine that contains transgenes for prostate-specific antigen (PSA) and three T-cell co-stimulatory transgenes: B7-1 (CD80), leukocyte function-associated antigen-3 (LFA-3), and intracellular-adhesion molecule-1 (ICAM-1) [138, 139].