GRP and neuroblastoma: Results in SK-N-SH neuroblastoma cells (188, 192) suggested that GRP can function in an autocrine growth manner in this neuroblastoma cell line, because conditioned media from these cells, when added to fresh SK-N-SH cells, stimulated significant growth, which was inhibited by the addition of an anti-GRP antibody (188), and the conditioned media contained high concentrations of GRP (192).