Epidermal growth factor--receptors on cultured human meningioma cells.

Equilibrium binding assays of EGF were performed on confluent cultures of 12 human meningiomas at early passage. In all meningiomas complete binding curves were obtained and the resulting ED 50 values ranged between 0.5 and 6.3 nM. In four cases (ED 50 values ranging from 1.5 nM to 3.0 nM) where saturation analysis was performed, the sites were saturable at similar levels (7 nM). In five cases additional experiments were undertaken to evaluate the biological response of cultured cells to EGF as assessed by 3H-thymidine incorporation. In all cases EGF was a potent stimulus and increased 3H-thymidine incorporation by 2.5 to 6-fold. Functionally intact EGF receptors appear to be a regular feature of meningiomas in cell culture and appear not to be related to histological classification.