Kallikrein 4 (KLK4)

Kallikreins are a subgroup of serine proteases having diverse physiological functions. Growing evidence suggests that many kallikreins are implicated in carcinogenesis and some have potential as novel cancer and other disease biomarkers. This gene is one of the fifteen kallikrein subfamily members located in a cluster on chromosome 19.

KLK4 was predominantly expressed in nuclei of basal cells in the prostate epithelium, in keeping with its distribution in prostate cancer cells in vitro. Adenovirus-mediated KLK4 expression dramatically induced proliferation of prostate cancer cells, at least in part, through significant alterations in cell cycle regulatory gene expression. Consistent with this data, small interfering RNA-mediated knockdown of endogenous KLK4 in LNCaP prostate cancer cells inhibited cell growth.