Gold nanostructures as photothermal therapy agent for cancer

Well-designed photothermal nanostructures have attracted many scientists pursuing a better means to accurately diagnose cancer and assess the efficacy of treatment. Recently, gold-based nanostructures (nanoshells, nanorods and nanocages) have enabled photothermal ablation of cancer cells with near-infrared (NIR) light without damaging normal human tissues and in particular, animal studies and early clinical testing showed the great promise for these materials. In this review article, we first discuss the mechanism of the cellular death signaling by thermal stress and introduce the intrinsic properties of gold nanostructures as photothermal agent for cancer treatment. Then the overview follows for evolving researches for the synthesis of various types of gold nanostructures and for their biomedical applications. Finally we introduce the optimized therapeutic strategies involving nanoparticle surface modification and laser operation method for an enhanced accumulation of gold nanostructures to the target cancer as well as for an effective cancer cell ablation.