In most, but not all, reports (186) that involve both PCR studies of GRP/GRPR mRNA expression (184, 187–190) and studies of immunoreactive GRP/Bn-related peptides (188, 191), they have reported their presence in neuroblastoma tumor tissue (188, 191) and in neuroblastoma cell lines [human IMR-32, SK-N-SH,BE(2)-C, murine Neuro2A cells] (100, 187, 188, 190, 192). This evidence concerns the gene GRP and neuroblastoma.