Previously we showed, through direct screening of a combinatorial peptide library in a cancer patient, that the selective homing peptides localized non-randomly to specific organs [1]; we also identified a cyclic peptide (sequence CGRRAGGSC) targeting prostate vasculature and prostate cancer as an interleukin-11 (IL-11) mimic [1], [2]. The gene discussed is IL11; the disease is prostate carcinoma.