We further showed that GnRH agonists, through activation of locally expressed GnRH receptors, exert a strong antiproliferative effect on prostate cancer cells, both in vitro and in vivo[12], [29], [30]; this antitumor activity is specific since it is completely abrogated after the silencing of the GnRH receptor by means of a specific siRNA [31]. This evidence concerns the gene GNRHR and prostate cancer.