Photosensitizers Combined With Heat Shock Protein Inhibitor APO For Photothermal Treatment Of Cancer

Because of the high incidence rate and mortality of cancer,it is necessary to seek more targeted and effective treatment methods.Traditional tumor treatment methods mainly include surgery,radiotherapy,and chemotherapy.However,these treatment methods have problems such as incomplete treatment and significant side effects^[1].In recent years,with the rapid development of synthetic technology,photothermal therapy（PTT）is considered to be one of the most promising therapeutic methods in the field of biomedicine.The therapeutic principle of PTT is to use materials with high photothermal conversion efficiency to absorb near infrared light（NIR）to produce a thermotherapeutic effect to eliminate tumors^[2].PTT has the advantages of small toxic and side effects,non-invasive,strong specificity,and high controllability.However,the self-protection mechanisms associated with heat shock proteins（HSPs）confer heat resistance on cancer cells,protecting them from the damage of PTT during photothermal therapy and thermal ablation.To minimize the heat resistance of cancer cells and improve the efficacy of PTT,a nanoparticle composed of a heat shock protein inhibitor APO,a photosensitizer Cy7-TCF with high photothermal conversion efficiency,and a redox double responsive bond（monosulfide bond）was developed.The nanoparticles can be enriched in tumor sites and stimulated by high levels of glutathione and hydrogen peroxide in the cells,breaking bonds to release heat shock protein inhibitors and photosensitizers.Under near-infrared light irradiation,Cy7-TCF generates heat to achieve the effect of photothermal therapy,killing tumor cells,while the APO released in situ can inhibit the level of heat shock protein,achieving the effect of mild photothermal therapy,reducing thermal damage to surrounding tissues.