title: Gastrin releasing peptide in human neuroendocrine tumours.
abstract: Neuroendocrine tumours of the lung and gut are known to possess bombesin-like immunoreactivity. The recent observation that gastrin releasing peptide (GRP), a 27 amino acid peptide isolated from the porcine intestine, may be the mammalian analogue of bombesin led us to look for this peptide in a variety of human neoplasms. Formalin-fixed tissues from 85 tumours were examined by the immunoperoxidase technique, using specific antisera to the GRP molecule (1-27) and the GRP fragment (1-16). Intense cytoplasmic GRP immunoreactivity was seen in thyroid medullary carcinomas (3/3), carcinoids of lung, pancreas, and intestine (22/36), and paragangliomas (2/3). Less frequent staining was present in pulmonary small cell (oat cell) carcinomas (1/8) and pituitary adenomas (1/6). Complete absence of immunoreactivity was observed in three phaeochromocytomas, five Merkel cell tumours, six neuroblastomas and 15 non-neuroendocrine tumours. Normal neuroendocrine cells of the thyroid (C-cells) and bronchial mucosa (Kulchitsky cells) exhibited GRP immunoreactivity; nerve fibres from all sites failed to demonstrate staining for GRP. In each positive case, the pattern of staining for GRP (1-27) and GRP (1-16) was identical, although the GRP (1-16) immunostaining was weaker. These findings indicate that bombesin immunoreactivity in human neuroendocrine cells and tumours is attributable to GRP-like molecules and that GRP is a useful marker of neuroendocrine differentiation in many tumours.
mesh_terms: D000236:Adenoma / Q000378:metabolism; D000310:Adrenal Gland Neoplasms / Q000378:metabolism; D000595:Amino Acid Sequence; D001839:Bombesin / Q000378:metabolism; D002276:Carcinoid Tumor / Q000378:metabolism*; D018288:Carcinoma, Small Cell / Q000378:metabolism; D019886:Gastrin-Releasing Peptide; D005755:Gastrins / Q000378:metabolism; D006801:Humans; D007414:Intestinal Neoplasms / Q000378:metabolism; D008175:Lung Neoplasms / Q000378:metabolism; D009369:Neoplasms / Q000378:metabolism*; D009490:Neurosecretory Systems / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D010673:Pheochromocytoma / Q000378:metabolism; D010911:Pituitary Neoplasms / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000378:metabolism
chemical_list: D005755:Gastrins; D010455:Peptides; D019886:Gastrin-Releasing Peptide; D001839:Bombesin