Somatostatin receptors in non-endocrine tumours.
The presence of cellular somatostatin receptors, particularly of subtype 2, has been reported in a large number of human primary non-neuroendocrine tumours, such as breast and colon cancer. Our aim was to evaluate whether subtype 2 expression may represent a prognostic factor in these tumours, and if the exact determination of its expression might help to identify patients eligible for a new treatment modality based on somatostatin analogues. Large groups of neuroblastomas as well as breast and colon cancers were studied for subtype 2 expression. In the two latter groups the expression of subtype 2 was evaluated both in tumour and in the corresponding normal tissue from the same patient, to correctly evaluate any modification of subtype 2 mRNA expression in cancer. Subtype 2 mRNA expression was measured with accurate quantitative retro transcription-polymerase chain reaction procedures (first, by competitive polymerase chain reaction and then, by real-time assays). When possible, results of mRNA measurement were compared with in vitro (in situ hybridisation and immunohistochemistry) and in vivo (octreoscan) demonstration of subtype 2 expression in the same patients. Our results seem to suggest the hypothesis that subtype 2 may represent a marker of cell differentiation in certain tumours, such as neuroblastoma, and another instance may be represented by breast and colon cancer. Beside this, the question whether subtype 2 may have an active role in inhibiting cancer cell proliferation, stays open.
Smitha
M C
MC
Endocrinology Unit, Department of Clinical Physiopathology, University of Florence, Florence, Italy.
Maggi
M
M
Orlando
C
C
D001943:Breast Neoplasms / Q000737:chemistry; D015179:Colorectal Neoplasms / Q000737:chemistry; D006801:Humans; D009369:Neoplasms / Q000737:chemistry* / Q000401:mortality; D009447:Neuroblastoma / Q000737:chemistry; D011379:Prognosis; D017481:Receptors, Somatostatin / Q000032:analysis*
D017481:Receptors, Somatostatin