Peptides stimulate growth hormone and IGF 1 production, promoting angiogenesis and cellular proliferation. In patients with undetected cancers, these peptides can accelerate tumor growth. Conventional imaging misses early cancers. Circulating tumor Expression and Purification of Recombinant GHK Tripeptides Are Able to Protect against Acute Cardiotoxicity from Exposure to Waterborne Copper in Zebrafish Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms Histamine2 receptor antagonists: Rapid development of tachyphylaxis with repeat dosing