A promising native GnRH analog to be used as a targeting moiety is lamprey GnRH-III (Glp-His-Trp-Ser-His-Asp-Trp-Lys-Pro-Gly-NH2), which binds to GnRH-Rs, has an insignificant endocrine effect in mammals and exerts a direct antiproliferative effect on both hormone-dependent and -independent cancer cells [7]–[9]. The gene discussed is GNRH1; the disease is cancer.