Conversely, in primary neuroblastomas TrkB-FL expression has been found to be associated with MYCN gene amplification, an unfavorable prognostic marker [21], and its activation by BDNF has been shown to promote neuroblastoma cell survival, resistance to chemotherapy, anoikis and metastasis [22,23,24]. The gene discussed is NTRK2; the disease is neuroblastoma.