NGF and astrocytoma (excluding glioblastoma): Thus, erinacine C induced neurotrophic activity secreted from 1321N1 astrocytoma cells—like recombinant NGF—mediates the differentiation of PC12 cells by likely activating PLCγ, PI3K, and MAPK a pattern of intracellular signaling characteristic for neurotrophin-stimulated Trk receptors.