BDNF and neoplasm: BDNF/TrkB signaling has been reported to be associated with tumor progression, metastasis, and response to chemotherapy in several human malignancies such as neuroblastoma [10], ovarian [11], head and neck [12], lung [13], hepatocellular [14], pancreatic [15], bladder [16], prostate [17], multiple myeloma [18], and breast tumor [19].