CELLULAR TARGETS OF EXOGENOUS TUMOR-NECROSIS-FACTOR-ALPHA (TNF-ALPHA)IN HUMAN GLIOMAS

To identify the cellular targets of TNF alpha in human gliomas, a tota l of 30 surgical specimens (12 glioblastomas, 4 anaplastic astrocytoma s, 3 astrocytomas, 7 brains adjacent to tumour (BAT), 4 histologically normal-appearing brains) were examined by in vitro binding technique using biotinylated TNF alpha. The TNF-binding sites (TNF-BS) were reco gnized in the tumour cells in 8 of the 12 glioblastomas, 3 of the 4 an aplastic astrocytomas and in all the 3 astrocytomas. The TNF-BS were a lso recognized in the vascular endothelial cells in all these cases. T he presence of TNF-BS in blood vessels ranged from 7.7 to 74.4% of the background vessels. This wide range of variation in the presence of T NF-BS within the tumour cells and tumour brood Vessels may be relevant to the variable response of individual tumours to TNF alpha therapy. Since the tissue of normal brain, which lacks TNF-BS, might hardly be affected by this cytokine, administration of TNF alpha may be consider ed as an adjuvant therapy in selected groups of patients.