ανß3 integrin-targeted ICG-derived probes for imaging-guided surgery and photothermal therapy of oral cancer.

Indocyanine green (ICG), as the only Federal Drug Administration (FDA) approved fluorescence imaging agent, has been widely applied in clinics for near-infrared (NIR) fluorescence imaging-guided surgery and photothermal therapy of cancers. However, its lack of target specificity and poor photo and photothermal stabilities seriously restrict its wide application in clinical practice. Herein, we developed ICG-derived NIR fluorescent probes consisting of a cypate fluorophore and one or two cyclic-(arginine-glycine-aspartic acid) (cRGD) peptides that can specifically target αvß3 integrin for accurate diagnosis and therapy of oral tumors. Probe Cy-2RGD has been demonstrated to possess bright NIR emission, great tumor targeting capability and a photothermal effect. Moreover, it could be successfully used for effective imaging-guided surgical resection as well as photothermal therapy of oral tumors. This work could provide a valuable tool for sensitive detection and accurate treatment of malignant tumors.

Light-initiated aggregation of gold nanoparticles for synergistic chemo-photothermal tumor therapy.

The combination of chemotherapy with photothermal therapy (PTT) has attracted extensive attention due to its excellent synergetic effect attributing to the fact that hyperthermia can effectively promote the tumor uptake of chemotherapeutic drugs. Herein, we propose a light-initiated gold nanoparticle (AuNP) aggregation boosting the uptake of chemotherapeutic drugs for enhanced chemo-photothermal tumor therapy. Novel light-responsive AuNPs (tm-AuNPs) were rationally designed and fabricated by conjugating both 2,5-diphenyltetrazole (Tz) and methacrylic acid (Ma) onto the surface of AuNPs with small size (∼20 nm). Upon the irradiation of 405 nm laser, AuNPs could be initiated to form aggregates specifically within tumors through the covalent cycloaddition reaction between Tz and Ma. Taking advantage of the controllable photothermal effect of Au aggregates under NIR excitation, improved enrichment of doxorubicin (DOX) in tumor tissues was realized, combined with PTT, resulting in outstanding synergetic anti-tumor efficacy in living mice. We thus believe that this light-initiated AuNP aggregation approach would offer a valuable and powerful tool for precisely synergistic chemo-photothermal tumor therapy.