Ghrelin: from discovery to cancer cachexia therapy

Purpose of review Despite the high prevalence of cancer cachexia, a condition that negatively impacts patients' prognosis and quality of life, effective therapies are still lacking. Ghrelin is a peptide hormone involved in anabolic and homeostatic functions, whose mechanisms of action are still only partially clarified, but with promising positive effects in cancer cachexia. Recently, the therapeutic administration of ghrelin in cancer has been shown to counteract loss of body mass and function, including muscle, and we specifically focus on this novel evidence. Recent findings Recent research aimed at developing new pharmacological therapies to prevent muscle wasting has used ghrelin and molecules acting as synthetic ghrelin receptor agonists with different modalities of administration and with high selectivity for specific targeted tissues. Positive effects of these therapies were described in cancer cachexia and chemotherapy-induced muscle wasting. New insights into the mechanisms of action of ghrelin revealed how its pleiotropic effects should be ascribed both to systemic anti-inflammation effect and to muscle-specific action through the activation of the antiatrophic molecular cascade. Summary Growing interest arises from the identification of ghrelin as a valid and well tolerated therapeutic option to counteract structural and functional wasting derived from tumour growth.