Effect of PEDF on the migration, M1 polarization, and phagocytic activity in macrophages: A new way to inhibit PCa?

Abstract

e16058 Background: Macrophages have been described as one of the main inflammatory components involved in prostate cancer (PCa) development. PEDF (Pigment Epithelium-Derived Factor) is a secreted angio-inhibitor with differentiation and suggested immune-modulating activities. PEDF expression has been shown to be down-regulated in PCa compared to normal tissues. Previously, we have demonstrated that PEDF re-expression in PCa cells curbs tumor growth in vivo and prolongs the survival of tumor-bearing mice. Others have shown that PEDF increased the recruitment of tumor-cytotoxic macrophages into MatLyLu rat prostate tumors suggesting a link between PEDF and inflammation in PCa. However, PEDF modes of action on macrophages still remain unknown and need further investigation. Methods: THP-1, RAW264.7 and primary macrophages treated with PEDF, its derived active P18 peptide or ctrl were used as models. Migration was assessed using Boyden chamber and 3D PCa spheroid assays. M1/tumor-cytotoxic polarization was te...