Gonadotropin-releasing hormone 2 (GNRH2)

Gonadotropin-releasing hormone 2 (GNRH2) is a decapeptide neurohormone that shares ~70% sequence identity with GNRH1 but differs in critical amino acids that enhance its stability and half-life. Unlike GNRH1, GNRH2 is predominantly expressed outside the hypothalamus, particularly in the midbrain and peripheral tissues. GNRH2 acts primarily through the GNRH2 receptor (GnRHR2)—a G protein-coupled receptor (GPCR) structurally distinct from classical GnRHR1—though the full-length functional receptor is absent in many mammals (notably, the human gene is disrupted, so only truncated isoforms may exist in humans). Functionally, GNRH2 modulates reproductive physiology and has been shown to exert potent anti-proliferative and pro-apoptotic effects in cancer cell lines, especially in endometrial and ovarian cancer, where it acts by modulating MAPK signaling and through downregulation of EGF-mediated pathways. Its analogues and antagonists are being investigated as therapeutics, although the precise therapeutic window and clinical efficacy, especially in humans, require further investigation due to species differences and uncertain receptor expression patterns[1][3].

Other names

Progonadoliberin-2Gonadoliberin-2GnRH-IILH-RH IIProgonadoliberin IILuliberin IILuteinizing hormone-releasing hormone IIGnRH-associated peptide 2GnRH-associated peptide II

Agonist and antagonist interaction with GnRH receptors (GnRHR2 primarily, with overlap at GnRHR1); Modulation of MAPK pathways (e.g., ERK1/2, p38); Activation of caspase-3 dependent apoptosis; Inhibition of EGF receptor signaling