Black M, Carey F A, Farquharson M A, Murray G D, McNicol A M
University Department of Pathology, Royal Infirmary, Glasgow, U.K.
J Pathol. 1993 Mar;169(3):329-34. doi: 10.1002/path.1711690309.
Neuroendocrine tumours of the lung may be associated with the ectopic adrenocorticotrophin (ACTH) syndrome and may synthesize and secrete ACTH-related peptides in the absence of the syndrome. However, immunocytochemical analysis may not confirm these biochemical findings, particularly in small cell carcinoma, which is poorly granulated. To investigate further the morphological evidence for expression of the pro-opiomelanocortin (POMC) gene in neuroendocrine lung tumours, we have examined a series of 46 small cell carcinomas and 13 carcinoid tumours of the lung by in situ hybridization for POMC mRNA using a digoxigenin-labelled oligoprobe. We have compared the findings with the immunocytochemical detection of ACTH and beta-endorphin. In situ hybridization was positive in 15 of 46 small cell carcinomas (33 per cent) and in 8 of 13 carcinoid tumours (62 per cent). Immunocytochemical staining was positive in only one carcinoid tumour. These in situ hybridization studies have corroborated biochemical data indicating POMC gene expression in a high proportion of lung neuroendocrine tumours. This suggests that the low levels of expression detected by immunocytochemistry may be due to low levels of hormone storage. Multivariate analysis showed a weak negative association between POMC expression and survival in small cell carcinomas, although this did not reach statistical significance.
肺神经内分泌肿瘤可能与异位促肾上腺皮质激素（ACTH）综合征相关，且在无该综合征的情况下也可能合成并分泌ACTH相关肽。然而，免疫细胞化学分析可能无法证实这些生化结果，尤其是在颗粒较少的小细胞癌中。为了进一步研究神经内分泌性肺肿瘤中阿黑皮素原（POMC）基因表达的形态学证据，我们使用地高辛标记的寡核苷酸探针，通过原位杂交检测了46例肺小细胞癌和13例肺类癌肿瘤中的POMC mRNA。我们将这些结果与ACTH和β-内啡肽的免疫细胞化学检测结果进行了比较。原位杂交在46例小细胞癌中有15例呈阳性（33%），在13例类癌肿瘤中有8例呈阳性（62%）。免疫细胞化学染色仅在1例类癌肿瘤中呈阳性。这些原位杂交研究证实了生化数据，表明在高比例的肺神经内分泌肿瘤中存在POMC基因表达。这表明免疫细胞化学检测到的低表达水平可能是由于激素储存水平较低。多变量分析显示，POMC表达与小细胞癌患者的生存率之间存在微弱的负相关，尽管这未达到统计学意义。
