BDNF and neoplasm: We further validated the downregulation of genes encoding several key ligands [brain-derived neurotrophic factor (Bdnf) and nerve growth factor (Ngf)] and receptors [Ngfr (also known as p75NTR) and Ntrk3 (also known as TrkC)] involved in neurotrophic factor-mediated Trk receptor signaling, which participates in tumor cell proliferation, survival and EMT through modulation of the PI3K, NF-κB, and MAPK pathways44 (Fig. 5e).