Expression of nerve growth factor and brain-derived neurotrophic factor in astrocytomas.

Neurotrophic factors (NTFs) are well known to serve critical functions in neural survival, neurite growth and cell differentiation in vivo and in vitro. Previous progress has indicated that nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), two NTF family members, may be involved in the process of tumor progression. In the present study, the expression of NGF and BDNF was detected using immunohistochemistry on 70 adult astrocytoma samples collected from distinct locations as well as of various pathological grades, with an additional 15 samples being collected from normal adult brain tissue to be used as controls. NGF and BDNF were identified to be expressed in all samples, and their positive cell expression rates in astrocytomas demonstrated a significant increase compared with that in the normal controls (P<0.05), particularly in grade III (P<0.05). In addition, the expression of NGF and BDNF exhibited a gradual decrease ranging from the temporal lobe, parietal lobe and cerebellum to the frontal lobe (P<0.05). The results of the present study suggest that the expression of NGF and BDNF is increased in astrocytomas, which is associated with the pathological grade and the astrocytoma location.