Although CHP707m is the first central nervous system PNET cell line proven to express NGF receptors, immunohistological survey of tissue sections prepared from human central nervous system PNETs showed that 13 of 35 contained NGF receptor-positive tumor cells.
These results demonstrate that NGFR is a biological marker for neuroepithelioma and that NGFR expression is heterogeneous for neuroblastoma cell lines.