gastrin-releasing-peptide and Intestinal-Neoplasms

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.

Topics: Adenoma; Adrenal Gland Neoplasms; Amino Acid Sequence; Bombesin; Carcinoid Tumor; Carcinoma, Small Cell; Gastrin-Releasing Peptide; Gastrins; Humans; Intestinal Neoplasms; Lung Neoplasms; Neoplasms; Neurosecretory Systems; Pancreatic Neoplasms; Peptides; Pheochromocytoma; Pituitary Neoplasms; Thyroid Neoplasms

Human neuroendocrine tumors are known to demonstrate immunoreactivity to the amphibian peptide bombesin. The recent observation that gastrin-releasing peptide (GRP), a 27 amino acid peptide first isolated from porcine intestine, may be the mammalian analog of bombesin led us to look for this peptide in intestinal carcinoid tumors. Formalin-fixed tissues from 20 of these tumors were examined by the immunoperoxidase technic, using specific antisera to the GRP molecule (1-27) and the GRP fragment (1-16). Intense diffuse cytoplasmic immunoreactivity was observed in carcinoids from the small intestine (7/10), appendix (4/5), and colon (1/5). In each positive case, the pattern of staining for GRP (1-16) and GRP (1-27) was identical. These findings indicate that bombesin-like immunoreactivity in human intestinal carcinoid tumors is attributable to GRP-like molecules and that GRP is a useful marker for neuroendocrine differentiation.

Topics: Adult; Aged; Carcinoid Tumor; Female; Gastrin-Releasing Peptide; Histocytochemistry; Humans; Immunochemistry; Intestinal Neoplasms; Male; Middle Aged; Nerve Fibers; Peptides