Objective: To compare the expressions of transforming growth factor alpha (TGFalpha), tumor necrosis factor alpha (TNFalpha), and vascular endothelial growth factor (VEGF) between pheochromocytoma (PHEO) tissues and normal adrenal medulla tissues.
Methods: The mRNA expressions of TGFalpha, TNFalpha, and VEGF detected by RT-PCR, were compared between 22 PHEO tissues and 18 normal adrenal medulla tissues (according with the principle of medical ethnics). Immunohistochemistry staining was performed on 27 PHEO tissues and 14 normal adrenal medulla tissues. The comparisons of the protein expression of TGFalpha, TNFalpha, and VEGF were analyzed in both of PHEO tissues and normal adrenal medulla tissues.
Results: Compared with normal adrenal medulla tissues, the expressions of TGFalpha and TNFalpha mRNA and protein were higher in PHEO tissues, and VEGF145 mRNA expression was also higher in PHEO tissues, while there was no significant difference of the mRNA expression of VEGF121 and VEGF165 between these two tissues. Positive staining rates for VEGF of endothelial cells and tumor cells were higher in PHEO tissues than in normal adrenal medulla tissues. Expressions of the TGFalpha, TNFalpha, and VEGF protein were higher in extra-adrenal PHEO than in adrenal PHEO. The TNFalpha immunohistochemistry staining rate was higher in the malignant or multiple PHEO than in the benign or single PHEO.
Conclusions: The mRNA and protein expressions of TGFalpha, TNFalpha, and VEGF are higher in PHEO tissues than those in normal adrenal medulla tissues. Expressions of these cytokines vary in PHEO with different characteristic.