NTRK2 and cancer: This is an important intercellular process that allows cancers to not only survive the presence of NK cells and CD8+ T cells, but to also persuade these cytolytic cells via AhR activation, leading to the ‘backward’ conversion of melatonin to NAS, to potentially provide trophic support for cancer stem-like cell survival and proliferation via released NAS activating TrkB on cancer stem-like cells.