Regulation of the enzymatic activity of prostate-specific antigen and its reactions with extracellular protease inhibitors in prostate cancer
Prostate-specific antigen (PSA) is a tissue-specific serine protease similar in structure to the trypsin-like glandular kallikreins but which is unique inasmuch as the enzyme activity is similar to that of chymotrypsin. The active enzyme is a single chain glycoprotein of 237 amino acids. The major form of PSA in serum is complexed to α1-antichymotrypsin (ACT). A small amount is free, non-complexed