Polyethylenimine-coated superparamagnetic iron oxide nanoparticles impair in vitro and in vivo angiogenesis.

Endothelial cells are essential to tumor vascularization and impairing their activity can potentially limit tumor growth. Since polyethylenimine (PEI)-coated superparamagnetic iron oxide nanoparticles (SPIONs) are bioactive nanosystems that modulate inflammatory macrophage responses and limit tumor cell invasion, we evaluated their effects on endothelial cell angiogenesis. PEI-SPION triggered proinflammatory gene profiles in a murine endothelial cell line and in primary human umbilical cord vein endothelial cells (HUVECs). These nanoparticles impaired endothelial cell migration and inhibited HUVEC tube formation. Magnetically tumor-targeted PEI-SPIONs reduced tumor vessel numbers and promoted intratumor macrophage infiltration in a tumor xenograft model. PEI-SPION treatment impaired M2 macrophage-promoted tube formation and affected HUVEC cytoskeleton by limiting Src and Cortactin activation. These mechanisms could contribute to PEI-SPION in vitro and in vivo antiangiogenic potential. These data confirm that PEI-SPION administration and application of a localized magnetic field could offer an affordable anti-angiogenic anti-tumoral targeted treatment that would complement other therapies.