Promotion of Wilms' tumor cells migration and invasion by mono-2-ethyhexyl phthalate (MEHP) via activation of NF-κB signals

Abstract

Wilms tumor is a pediatric kidney cancer associated with inactivation of the WT1 tumor-suppressor gene in 5–10% of cases. There is an urgent need to illustrate risk factors which can trigger the motility of Wilms tumor cells. Our present study revealed that mono-(2-ethylhexyl) phthalate (MEHP) exposure can significantly increase the in vitro migration and invasion of G401 and WiT49 cells. Real time PCR and western blot analysis revealed that MEHP treatment can increase the expression of metalloproteinase-2 (MMP-2) and MMP-9, while had no effect on the expression of MMP-1, MMP-3, or MMP-12. The si-MMP-2 and si-MMP-9 can reverse MEHP induced migration and invasion of G401 cells. MEHP can activate both ERK1/2 and p65 in WT cells, while had no obvious effect on Akt or PKA. However, only BAY 11-7082, the inhibitor of NF-κB, while not ERK1/2 (PD 98059), can reverse MEHP induced migration and invasion of WT cells. BAY 11-7082 also can attenuate MEHP induced up regulation of MMP-2 and MMP-9. The inhibitor of estrogen receptor reversed MEHP induced activation of NF-κB and up regulation of MMP-2/-9. In addition, MEHP also increased the mRNA and protein expression, nuclear translocation, and transcriptional activities of NF-κB in WT cells. Collectively, our study found that MEHP stimulated the Wilms' tumor progression via NF-κB signals.