TNF and cancer: Cancer anorexia involves alterations in signaling pathways modulating energy intake mediated by hormones (e.g., leptin), neuropeptides (e.g., Neuropeptide Y [NPY]), inflammatory cytokines (e.g., interleukin-1 [IL-1], interleukin-6 [IL-6], tumor necrosis factor-alpha [TNF- α], and neurotransmitters (e.g., serotonin and dopamine) [17].