Immunolocalization of dehydroepiandrosterone sulfotransferase in normal and pathologic human adrenal gland

Dehydroepiandrosterone sulfotransferase (DHEA-ST) catalyzes the conversion of dehydroepiandrosterone (DHEA) to dehydroepiandrosterone sulfate (DHEA-S) in the adrenals. Both DHEA and DHEA-S are quantitatively the most important corticosteroids in human. In this study, DHEA-ST was immunolocalized in normal (5 cases) and neoplastic human adrenal glands (33 cases), using a specific IgG fraction raised against the enzyme. DHEA-ST was present in almost all the zona reticularis cells and some cortical cells demonstrating lipid depletion in the zona fasciculata but not in the zona glomerulosa of the normal adrenal. This finding is consistent with adrenocorticotrophic hormone dependency of the enzyme expression. In adrenocortical adenoma, DHEA-ST immunoreactivity was observed in all the cases of Cushing's adenoma, adenoma associated with pre-Cushing's syndrome, nonfunctioning, hormonally inactive adenoma, and two of seven cases of aldosteronoma, but distribution of immunoreactivity was markedly heterogeneous among the adenoma cases. In attached non-neoplastic adrenal glands of the adenoma, intense and diffuse immunoreactivity was observed in the zona reticularis cells in all the cases of aldosteronoma and five of six of the nonfunctioning hormonally inactive adenoma, but DHEA-ST immunoreactivity was not observed or sporadic in the attached adrenal glands of Cushing's adenoma and adenoma with pre-Cushing's syndrome. These results in the attached adrenal gland may be correlated with decreased DHEA-ST expression due to autonomous neoplastic cortisol secretion and subsequent adrenocorticotrophic hormone suppression. In adrenocortical carcinoma, DHEA-ST was observed in all the cases, but the relative immunointensity of carcinoma cells was weak compared to that of the zona reticularis of the normal adrenal and adenoma.