Expression of melanin-concentrating hormone receptor messenger ribonucleicacid in tumor tissues of pheochromocytoma, ganglioneuroblastoma, and neuroblastoma

Expression of melanin-concentrating hormone (MCH) receptor messenger ribonu cleic acid (mRNA) was studied by RT-PCR and Northern blot analysis in human brain; pituitary; adrenal glands; tumor tissues of adrenal tumors, ganglio neuroblastomas, and neuroblastomas; and various cultured tumor cell lines. RT-PCR analysis showed that MCH receptor mRNA was widely expressed in brain tissues, pituitary, normal portions of adrenal glands (cortex and medulla) , tumor tissues of adrenocortical tumors (12 of 13 cases), pheochromocytoma (all 7 cases), ganglioneuroblastoma (1 case), neuroblastoma (all 5 cases), and various cultured tumor cell lines (6 of 7 cell lines), including 2 neu roblastoma cell lines. Northern blot analysis showed the expression of MCH receptor mRNA (similar to2.4 kb) only in the tumor tissues of 5 pheochromoc ytomas, 1 ganglioneuroblastoma, and 4 neuroblastomas, indicating that the e xpression levels of MCH receptor mRNA are much higher in these tumors than in the other tissues. These findings raised the possibility that MCH or MCH -like peptides may be related to the pathophysiology of these neural crest- derived tumors.