GNRH1 and cancer: Receptors for the human gonadotropin releasing hormone (GnRH-I, <EHWSYGLRPG-NH2, <E is pyroglutamic acid) were not only identified in the pituitary, but also in various reproductive system-related cancers, such as breast, prostate and ovarian cancers, as well as non-reproductive cancers, such as colon and lung cancer [3].