The effect of nerve growth factor on undifferentiated glioma cells.

Nerve growth factor (NGF) treatment of rats bearing implanted cells of an anaplastic glioma clone (F-98) led to a decreased tumor growth rate and increased survival time. Similar, but less pronounced, effects were observed if the cells were pretreated with NGF for 24 h before implantation. NGF also reduced the in vitro growth rate of F-98 and contributed to cellular maturation. Several well differentiated cell lines and clones were not visibly affected by NGF using the above parameters. We concluded that NGF has little or no effect on differentiated glioma cells, but significantly affects undifferentiated glioma cells by retarding their growth and inducing maturation.