CSF2 and prostate cancer: In vitro killing of PSA peptide-pulsed cell line as well as PSA-expressing cell line (LNCaP) by human cytotoxic T lymphocytes was demonstrated by Correale et al.[1] A Phase 1 trial of patients who failed primary therapy for prostate cancer demonstrated that a vaccinia virus containing the entire human PSA gene could be given with minimal toxicity.[2] Ten patients in this study were given granulocyte/macrophage colony-stimulating factor (GM-CSF) at the vaccine site.