Succesful separation between benign prostatic hyperplasia and prostate cancer by measurement of free and complexed PSA

摘要: Prostate-specific antigen (PSA) is a serine protease belonging to the human glandular kallikrein gene family [1–3]. The expression of PSA mainly androgen dependent, and detection very high levels restricted prostate tissue, but extraprostatic production at much lower has been demonstrated in several other tissues such as normal malignant breast epithelium, endometrium, bulbourethral glands [4–10]. synthesized by columnar epithelium ducts acini prostate, not any cells tissue. It secreted concentrations (0.2-5mg/mL) into seminal fluid [4–6,11]. an inactive precursor [2,3,12]. Like kallikreins, PSA-precursor processed stepwise release leader peptide followed liberation activation that results conversion zymogen enzymatically active [12]. This process may occur parallel with secretory from most probably occurs prior ejaculatory mixing secretions vesicles, epididymis, since ejaculates collected subjects defective vesicles deferent [1]. protease(s) responsible for processing have identified. mature 237-amino-acid form single-chain extensive structural similarity kallikreins [1,12–14]. However, substrate specificity uniquely different trypsin-like resembles chymotrypsin, catalyzes hydrolysis bonds’ carboxy-terminal residues tyrosine leucine [15–17]. Synthetic substrates chymotrypsin can be used measure activity, they are hydrolyzed less efficiently than therefore both nonspecific insensitive detecting activity [16].