Photothermal therapeutic effect of PEGylated gold nano-semicubes in chemically-induced skin cancer in mice

- PEG-GNSCs with laser inhibited Sk-Mel-28 cells growth (IC50 3.41 μg/ml).
- PEG-GNSCs with laser inhibited skin tumor volumes in mice.
- PEG-GNSCs with laser inhibited tumor NO, COX-2, and VEGF.
- PEG-GNSCs with laser induced tumor TNF-α with no change in 5-LO.
- PEG-GNSCs with laser induced tumor apoptosis and histone acetylation.

BackgroundThe photothermal properties of gold nanoparticles (GNPs) are promising therapeutic modality for cancer. The study objective is to evaluate the therapeutic effect of the prepared PEGylated gold nano-semicubes (PEG-GNSCs) in skin cancer. The synthesized PEG-GNSCs were intermediate between cubic and rod shapes (low aspect ratio- rods).MethodsIn vitro toxicity was investigated in human skin melanoma Sk-Mel-28 cells, and skin squamous cell carcinoma was induced in CD1 mice by dimethylbenzanthracene (DMBA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA).ResultsThe calculated IC50 in Sk-Mel-28 cells was 3.41 μg/ml of PEG-GNSCs, in presence of laser exposure. Photothermal therapy using laser-stimulated PEG-GNSCs resulted in inhibited volume of skin tumors. Our findings indicated that the inflammatory mediators, nitric oxide and cycloxygenase-2, were inhibited in mice after being treated with low and high doses of PEG-GNSCs, accompanied with laser exposure. However, the tumor necrosis factor -α was markedly elevated, while there was no change in 5-lipoxygenase. The pro-angiogenic factor vascular endothelial growth factor was inhibited, while histone acetylation and apoptosis were induced in tumor-bearing groups, after being treated with laser-stimulated PEG-GNSCs.ConclusionThe present study indicated the promising photothermal therapeutic effect of laser-stimulated PEG-GNSCs as an effective modality to inhibit the tumor growth, the angiogenesis and partially the inflammation.