GHSR and lung cancer: A therapeutic potential of ghrelin for the treatment of lung cancer was suggested by the observation that GHSR expression is elevated in cancerous vs. normal lung tissue [222,223] and that ghrelin exerts anti-proliferative and pro-apoptotic effects on these cells in vitro [222], although a later study in a mouse lung cancer model was unable to show that ghrelin receptor agonism reduced the tumor growth progression [113].