Vaccination of prostate cancer patients with recombinant viral-based vaccines expressing PSA, in combination with the costimulatory molecule B7-1 and standard RT to the prostate (70 Gy of RT in 1.8–2 Gy fractions), resulted in a threefold increase in PSA specific T cells and evidence of generating T cells against other prostate-specific antigens in 76% of patients (Gulley et al., 2005). The gene discussed is KLK3; the disease is prostate cancer.