Liposome-templated gold nanoparticles for precisely temperature-controlled photothermal therapy based on heat shock protein expression

Mild temperature photothermal therapy is gaining more and more attention due to high safety, high specificity and moderate efficacy. However, the therapeutical outcome of mild photothermal therapy is limited due to the overexpression of heat shock proteins (HSPs). Therefore, the precise management of HSP expression is the key to improvement of mild temperature photothermal therapy. However, the correlation between HSP expression and photothermal temperature in vivo is still unclear. To precisely control the photothermal temperature by managing the HSP expression, we quantified the HSP expression at different photothermal temperatures after irradiation on liposome-templated gold nanoparticles, which have high photostability, high photothermal conversion efficiency and low temperature fluctuation (smaller than 1 ℃). We found that the expression of HSP70 was least at 47 ℃, which was the optimal temperature for HSP management. We chose to co-administrate HSP70 inhibitor during 47 ℃ photothermal therapy, leading to greatly enhanced tumor inhibition. Our precise temperature-controlled photothermal therapy based on HSP expression offers a new strategy for clinical tumor photothermal therapy.