Kallikreins are a group of serine proteases manifesting diverse physiological functions. The glandular kallikreins are a distinct group of serine proteases with an ability to release vasoactive peptides from kininogen in vitro, although the kininogenase activity of different kallikreins is highly variable. Glandular kallikreins cleave Met-Lys and Arg-Ser bonds in kininogen to release Lys-bradykinin. Many kallikrein genes are differentially expressed in various malignancies. Human glandular kallikrein (hK2, encoded by the KLK2 gene) is an emerging tumor marker for prostate cancer.Synonyms: Glandular kallikrein-1, Kallikrein 2, Kallikrein2, Tissue kallikrein-2, hGK-1, hK2