Howlett T A, Price J, Hale A C, Doniach I, Rees L H, Wass J A, Besser G M
Clin Endocrinol (Oxf). 1985 Jan;22(1):91-101. doi: 10.1111/j.1365-2265.1985.tb01069.x.
A 41-year-old man presented with Cushing's syndrome and the biochemical features of ectopic ACTH production. Investigation revealed mediastinal metastases from a medullary carcinoma of the thyroid. The peripheral plasma contained grossly elevated levels of bombesin-like immunoreactivity (irBombesin) as well as calcitonin; blood sampling via a venous catheter confirmed a gradient of irBombesin, but not of ACTH, in the mediastinal vein draining the tumour. On extraction the tumour contained a bombesin-like peptide, but not vasopressin or corticotrophin releasing factor and only very low levels of ACTH; immunohistochemical studies showed positive immunostaining for bombesin and calcitonin but none for ACTH or CRF. No ACTH was released from dispersed tumour cells in vitro. However an extract of the tumour stimulated ACTH release in vitro from perifused dispersed rat anterior pituitary cells. This is the first reported case of Cushing's syndrome due to ectopic production of a bombesin-like peptide, causing excessive pituitary ACTH secretion.
一名41岁男性患有库欣综合征及异位促肾上腺皮质激素（ACTH）分泌的生化特征。检查发现甲状腺髓样癌纵隔转移。外周血浆中蛙皮素样免疫反应性物质（irBombesin）和降钙素水平显著升高；通过静脉导管采血证实，引流肿瘤的纵隔静脉中irBombesin存在梯度变化，但ACTH没有。肿瘤提取物中含有一种蛙皮素样肽，但没有血管加压素或促肾上腺皮质激素释放因子，且ACTH水平极低；免疫组化研究显示蛙皮素和降钙素免疫染色呈阳性，而ACTH或促肾上腺皮质激素释放因子（CRF）免疫染色阴性。体外分散的肿瘤细胞未释放ACTH。然而，肿瘤提取物在体外可刺激灌流的分散大鼠垂体前叶细胞释放ACTH。这是首例因异位产生蛙皮素样肽导致垂体ACTH分泌过多而引起库欣综合征的报道病例。
