TWEAK promotes ovarian cancer cell metastasis via NF-κB pathway activation and VEGF expression

The poor prognosis of human ovarian cancer is partly due to its metastasis and recurrence. It has been demonstrated that tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK)-fibroblast growth factor inducible-14 (Fn14) signaling system may be a potential regulator of human tumorigenesis. The objective of this study was to understand the effect of TWEAK on ovarian cancer metastasis. We recently showed that activation of Fn14 signaling by TWEAK promoted cell migration and invasion in human HO-8910PM cells. Treating HO-8910PM cells with TWEAK resulted in the activation of nuclear factor-kappa B (NF-kappa B) and subsequently the translocation of NF-kappa B from cytoplasm to nucleus. In addition, TWEAK promoted vascular endothelial growth factor (VEGF) protein expression, and this effect was dependent upon NF-kappa B transcriptional activity. Blocking the NF-kappa B pathway with PDTC suppressed TWEAK-induced up-regulation of VEGF protein expression and cell metastasis. Our results suggest that TWEAK-Fn14 functions, in part, through the NF-kappa B signaling pathway to up-regulate VEGF expression to foster ovarian cancer cell metastasis. Targeted therapy against TWEAK-Fn14 signaling system as an adjuvant to surgery may improve clinical management of invasive ovarian cancer cells and advance the outcome of this devastating cancer. (C) 2009 Elsevier Ireland Ltd. All rights reserved.