EGFR and glioma: At poly IC concentrations of up to 10 μg/ml, no significant effect was observed on the parental U87MG cells, which express 100,000 of EGFR per cell [10], on cells that over-express the mutated Δ(2–7)EGFR (U87MGΔEGFR), or on glioma cells lacking the EGFR (U138MG [11]) (Figure 1A).