Gold nanoparticles regulate tight junctions and improve cetuximab effect in colon cancer cells

Colon cancer (CC) is the second cause of cancer death worldwide. The use of nanoparticles for drug delivery has been increasing in cancer clinical trials over recent years. We evaluated cytotoxicity of citrate-capped gold nanoparticles (GNPs) and the role they play on cell–cell adhesion. We also used GNP for delivery of cetuximab into different CC cell lines. CC cells with well-formed tight junctions impair GNP uptake. Noncytotoxic concentration of GNP increases paracellular permeability in Caco-2 cells in a reversible way, concomitantly to tight junctions proteins CLDN1 and ZO-1 redistribution. GNP functionalized with cetuximab increases death of invasive HCT-116 CC cells. GNP can be used for drug delivery and can improve efficiency of CC therapy.