Indeed, given that FS cells have been shown to modulate the hormone secretion of the normal APG [22] and that relationships between S100B + cells and the preoperative levels of growth hormone and of prolactin were revealed in acromegaly patients [25], it would not be surprising if FS cells also have an effect on hormone production/secretion by gonadotroph tumour cells. The gene discussed is S100B; the disease is acromegaly.