The Role Of Cytokines In The Pathogenesis Of Pheochromocytoma

Objective:Cytokines are very important in regulating cell growth and functions, and related to the pathogenesis of many diseases. The pathogenesis of pheochromocytoma is complicated and remains unclear. Up to now, we have found few reports about the relationship between the cytokines and the pathogenesis of pheochromocytoma. The aim of the following research is to study the effect of some cytokines on the proliferation and apoptosis of pheochromocytoma cells, and to compare the expressions of these cytokines in pheochromocytoma tissues with those in normal adrenal medulla tissues. We chose transforming growth factor α(TGFα), tumor necrosis factora(TNFa) and vascular endothelial growth factor(VEGF) in our research, which are tightly related to the development of many other tumors.Methods:1. The human pheochromocytoma cells were collected with sequential enzyme digestion. Cell identification was performed with several methods, which were detection of catecholamines in the culture medium, paraformaldehyde-induced histofluorescence of catecholamines and immunohistochemical staining of CgA and NSE. Cell growth was observed with MTT method.2. The pheochromocytoma samples for RT-PCR experiment were taken from 22 cases during the operations of tumor resection, while the normal adrenal medulla tissues came from 18 cases of the fresh accidental death. The mRNA expressions of TGFa, TNFa and VEGF, detected by the means of RT-PCR, were compared between pheochromocytoma and the normal adrenal medulla tissues.3. Immunostaining was performed on 27 pheochromocytomas and 14 normal adrenals. Both the tumor and normal specimens were employed from the stored samples in the department of pathology, the Union Hospital. The comparisons of the protein expression were analyzed both between tumors and normal controls and between tumors with different clinical features.4. The growth of human pheochromocytoma cells and rat pheochromocytoma PC12...