Background: It has been reported that vasoactive intestinal peptide (VIP)-producing tumors accompanied by watery diarrhea, hypokalemia, and achlorhydria (WDHA) syndrome often produce multiple hormones biochemically and immunohistochemically.
Methods: The authors examined the distribution of several peptides--VIP, peptide histidine methionine (PHM), neuropeptide Y (NPY), methionine-enkephalin (M-EK), somatostatin (SS), substance-P (Sub-P), corticotropin-releasing hormone, and tyrosine hydroxylase--with immunohistochemical studies and an in situ hybridization method in three ganglioneuroblastomas with WDHA syndrome. All patients had an extremely elevated plasma level of VIP.
Results: Peptides examined immunohistochemically in the tumor were all detectable in ganglionic cells and some neurites. The coexistence of those peptides was observed with serial section staining. The presence of messenger RNA of VIP/PHM-27, NPY, and SS was detectable in the cytoplasm of the tumor cells with the in situ hybridization.
Conclusions: It was shown that multiple genes of peptides are expressed simultaneously and translated to proteins in those tumors.