GRP and neuroblastoma: The GRPR selective agonist, GRP stimulated growth of human neuroblastoma cell lines [SH-SY5Y, SK-N-SH, IMR-32, LAN-1, BE(2)-C] in culture (100, 188, 192, 198, 201–203), as well as in xenografts (SK-B-SH cells) in nude mice (100, 202), and induced S-phase progression in SK-N-SH neuroblastoma cells (198).