IGF1 and pachyonychia congenita: A significant decrease in serum level of prostate-specific antigen (PSA), hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF-1), and IGF binding protein-3 (IGFBP-3) was observed with no elevation of liver enzymes in men with PC after a short-term supplementation with daily doses of polyphenon E (a total of 1.3 g of tea polyphenols) [24].