Alterations on HeLa cell actin filaments induced by PEGylated gold nanorod-based plasmonic photothermal therapy

The actin cytoskeleton plays a crucial role in dynamic processes such as cell adhesion and intracellular movement. For cancer cells, both mechanisms are involved in metastasis. Plasmonic photothermal therapy (PPT) is postulated to lessen undesirable damage of both the surrounding healthy cells and tissue. We have examined the actin filaments of HeLa cells treated in vitro with PEGylated gold nanorod (_PEGGNR)-based PPT. Our results show that 5 min of _PEGGNR-PPT induces irreversible damages on the cytoskeleton network, which initiate with the accumulation of F-actin stress fibers and evolve into cell shrinkage and apoptosis. The PPT mediated by _PEGGNRs results in 60.5% of death cells by apoptosis, in which F-actin distribution is significantly accumulated in a reduced area (2.5 times higher than non-treated). Such results suggest that the _PEGGNRs could be responsible for compromising the cytoskeleton integrity of HeLa cells while inducing apoptosis. Graphical abstract: [Figure not available: see fulltext.].