The growth hormone receptor (GHR) is a cell surface receptor that mediates the pleiotropic effects of growth hormone (GH) on growth, metabolism, and cellular function. Upon GH binding, GHR undergoes dimerization and recruits the cytoplasmic tyrosine kinase JAK2, initiating a phosphorylation cascade 1. This activation leads to recruitment of signal transducers and activators of transcription (STATs), mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinase (PI3K) pathways that regulate transcription of GH-responsive genes and control metabolic effects 2. The circulating GH-binding protein (GHBP) is a proteolytic product of GHR that serves as a marker of receptor number and function 3. GHR signaling promotes insulin-like growth factor-I (IGF-I) synthesis, the principal growth-promoting product of GH action 4. Loss-of-function GHR mutations cause severe growth hormone insensitivity syndromes, including Laron syndrome, characterized by post-natal growth failure and IGF-I deficiency 35. Conversely, GHR signaling excess in acromegaly associates with increased cancer and type 2 diabetes risk, suggesting GHR-derived IGF-I independently influences neoplastic progression through effects on DNA damage and apoptosis 4.