Epithelial-mesenchymal transition in prostate cancer and the potential role of kallikrein serine proteases.

Prostate cancer is associated with significant mortality once the tumour has spread outside the gland. Epithelial-mesenchymal transition (EMT) has been proposed to facilitate this dissemination of tumour cells. In this article we summarize the evidence for EMT in prostate cancer, drawing on the expression of EMT-related markers and the functions of factors known to induce EMT in other systems. We also discuss our recent findings that two members of the tissue kallikrein family of serine proteases, prostate-specific antigen (PSA/KLK3) and kallikrein-related peptidase 4 (KLK4), lead to EMT-like changes in PC3 prostate cancer cells.