BDNF and central nervous system cancer: Rat C6 cells were confirmed to express the TrkB receptors (Fig. 1E), and previous studies have shown they respond to BDNF by proliferating.43 It was confirmed that application of recombinant mBDNF significantly increased rat C6 glioma cell number, which was apparent at concentrations of 100 and 200 ng/mL (Fig. 1F).