EXPRESSION OF C-ERBB2 IN HUMAN NEUROBLASTOMA TISSUES, ADRENAL-MEDULLAADJACENT TO TUMOR, AND DEVELOPING MOUSE NEURAL CREST CELLS

We have examined the expression of c-ErbB2 in primary neuroblastoma ti ssues, mouse neural crest-derived tissues, and human adrenal gland adj acent to neuroblastoma tissue and of age-matched controls, c-ErbB2 exp ression was observed in approximately 60% of cases analyzed, and there were two staining patterns; one showed focal and cytoplasmic and the other showed diffuse and membrane staining patterns, The expression of c-ErbB2 in neuroblastoma tissues was confirmed by reverse transcripti on polymerase chain reaction and Western blot analysis. Diffuse and me mbrane staining of c-ErbB2 was well correlated with high urinary catec holamine secretion. In mouse tissues, cytoplasmic expression of c-ErbB 2 was observed in immature peripheral neurons and adrenomedullary cell s, In mature neurons, the immunoreactivity was confined to the plasma membrane, These results suggest that the expression of c-ErbB2 in neur oblastoma rejects the phenotype of developing peripheral neurons, Post natal human and mouse adrenomedullary cells laced c-ErbB2 immunoreacti vity, although apparently normal adrenomedullary cells adjacent to neu roblastoma tissues showed strong cytoplasmic expression of c-ErbB2. It is not known whether the phenotypic conversion of adjacent adrenal me dullary cells had occurred before or after tumor progression at presen t.