Interactions between different tissues/organs and skeletal muscle in the development of wasting associated with cancer cachexia. The events and metabolic alterations that take place in different tissues/organs during cancer cachexia may be related with the loss of muscle tissue. Indeed, muscle wasting may be influenced by the liver, inflammatory response, and by adipose tissues, particularly white fat. Brown adipose tissue could partially account for the energy inefficiency associated with hypermetabolism in the cancer patient. Brain, basically by modulation of appetite, also contributes to muscle wasting. The gut may be responsible for both malabsorption and changes in ghrelin production and, finally, the heart could also be a source of inflammatory mediators contributing to further muscle wasting.