NGFR and astrocytoma (excluding glioblastoma): Expression of p75NTR protein was detected in 20 of 40 human glioma patient specimens (50%) (one of 11 low-grade astrocytomas [8%], two of nine mid-grade astrocytomas [22%], and 17 of 20 glioblastoma multiforme (GBM) specimens [85%]) and was undetectable in normal human brain (zero of five).