Immunohistochemical Expression of Somatostatin Type 2A Receptor in Neuroendocrine Tumors

• Published in: Clinical cancer research 1999-11, Vol.5 (11), p.3483-3487
• Main Authors: KIMURA, N, PILICHOWSKA, M, DATE, F, KIMURA, I, SCHINDLER, M
• Format: Article
• Language: English
• Subjects: Adrenal Gland Neoplasms - genetics; Adrenal Gland Neoplasms - pathology; Antibody Specificity; Biological and medical sciences; Carcinoid Tumor - genetics; Carcinoid Tumor - pathology; Carcinoma, Small Cell - genetics; Carcinoma, Small Cell - pathology; Female; Ganglioneuroma - genetics; Ganglioneuroma - pathology; Gastroenterology. Liver. Pancreas. Abdomen; Humans; Immunohistochemistry; In Situ Hybridization; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Lung Neoplasms - genetics; Lung Neoplasms - pathology; Male; Medical sciences; Neuroblastoma - genetics; Neuroblastoma - pathology; Neuroendocrine Tumors - genetics; Neuroendocrine Tumors - pathology; Pancreatic Neoplasms - genetics; Pancreatic Neoplasms - pathology; Pheochromocytoma - genetics; Pheochromocytoma - pathology; Receptors, Somatostatin - analysis; Receptors, Somatostatin - genetics; RNA, Messenger - analysis; RNA, Messenger - genetics; Thyroid Neoplasms - genetics; Thyroid Neoplasms - pathology; Tumors
• ISSN: 1078-0432; 1557-3265

Somatostatin (SS) and SS analogues inhibit the growth of various kinds of endocrine and exocrine cells via the SS receptor (SSTR). Carcinoid tumor is representative of the tumors treatable by SS analogues. We examined the expression of SSTR2A by immunohistochemical and in situ hybridization methods with a specific antibody against a synthesized 20-amino acid peptide of the COOH terminus of human SSTR2A and oligonucleotide probes in 62 endocrine tumors of various kinds: pancreatic endocrine tumor; carcinoid; neuroendocrine carcinoma; medullary thyroid carcinoma; pheochromocytoma; and small cell carcinoma of the lung, neuroblastoma, and ganglioneuroma. SSTR2A was expressed in 87% of these tumors and at both primary and metastatic sites. The immunohistochemical reactivity of SSTR2A was strong on the cell membrane and less intense in the cytoplasm of the tumor cells. SSTR2A mRNA was also detected in the tumor cells. The results indicate the usefulness of SSTR2A analogues for the treatment of neuroendocrine tumors, even metastatic ones: metastatic carcinoids, metastatic pheochromocytomas, tumors that adhered to large vessels, and neuroendocrine carcinomas.