COEXPRESSION OF TRANSFORMING GROWTH-FACTOR-ALPHA AND EPIDERMAL GROWTH-FACTOR RECEPTOR IN CAPILLARY HEMANGIOBLASTOMAS OF THE CENTRAL-NERVOUS-SYSTEM

The expression of epidermal growth factor receptor (EGFR) and the pre- pro form of one of its ligands, transforming growth factor-alpha (TGF- alpha), was studied by Northern blotting in a series of 14 capillary h emangioblastomas of the central nervous system. A constant coexpressio n of EGFR and pre-pro-TGF-alpha mRNAs was found. Immunocytochemical in vestigation of an extended series of 51 capillary hemangioblastomas re vealed that the stromal cells in these tumors showed immunoreactivity with monoclonal antibodies to EGFR and TGF-alpha. Analysis of gene dos age by Southern blotting in 20 tumors indicated a normal gene copy num ber of EGFR and TGF alpha in all cases. Our findings suggest that auto crine and/or juxtacrine growth stimulation via the EGFR may contribute to tumor growth in capillary hemangioblastomas.