GH1 and acromegaly: Excessive GH stimulates the liver to produce insulin-like growth factor-1 (IGF-1) (2), and long-term overproduction of GH and IGF-1 promotes excessive hyperplasia of soft tissues, bone, and cartilage throughout the body, leading to the typical signs and symptoms of gigantism or acromegaly in patients, and can cause multi-organ/system complications such as cardiovascular, respiratory, and digestive systems (3, 4).