IMMUNOHISTOCHEMICAL LOCALIZATION OF FIBROBLAST GROWTH-FACTOR-I (FGF-1), FGF-2 AND FIBROBLAST GROWTH-FACTOR RECEPTOR-1 (FGFR-1) IN PLEOMORPHIC ADENOMA OF THE SALIVARY-GLANDS

Fibroblast growth factor-1 (FGF-1) and FGF-2 are heparin-binding polyp eptides that are potent mitogens for neoplastic cells. In this study, fibroblast growth factor-1 (FGF-I), FGF-2, and fibroblast growth facto r receptor-1 (FGFR-1) were immunohistochemically analyzed in 10 patien ts with pleomorphic adenoma of the salivary gland by using specific mo noclonal antibodies. The tumor tissues were histopathologically classi fied as: tubular, solid, myxoid. or chondroid. Both FGF-1 and FGF-2 we re immunohistochemically identified in the tumor cells of all histolog ical types. In addition, immunoreactive FGF-2 was also found in the ba sement membrane of tubular type tumor cells. Conversely, FGFR-1-positi ve tumor cells were essentially confined to the tubular and solid area s of tumors. Tumor cells in the myxoid and chondroid areas were FGFR-1 immunonegative. These results suggest that the co-expression of FGF a nd its receptor appears to be related to the proliferative activity of tumor cells in the tubular and solid areas, whereas loss of FGF recep tor expression may be associated with the differentiation of tumor cel ls into myxoid and chondroid tissue types.