BDNF and neoplasm: Several studies point out the involvement of BDNF in tumor pathogenesis through TrkB in different cancers [3] such as colon [7, 8], lung [9-11], breast [12] neuroblastoma [13, 14], ovary [15] prostate [16], head and neck [17], as well as lymphoid malignant B cells and myeloma [18-20].