BDNF and cancer: Upregulation of the BDNF/TRKB pathway in cancer cells promotes cell proliferation and survival via the RAS/MAPK, PI3K/PDK1/AKT, and PLCγ pathways, and induces anoikis suppression and epithelial-mesenchymal transition (EMT) via the induction of Zeb1, Twist, and/or Snail15–18.