Enhanced cellular uptake of near-infrared triggered targeted nanoparticles by cell-penetrating peptide TAT for combined chemo/photothermal/photodynamic therapy.

Recently, the emergence of cell-penetrating peptides (CPPs) like TAT has greatly improved the efficiency of cancer therapy by enhancing cellular uptake of nanomaterials. Here, we designed a near-infrared (NIR) triggered TAT-based targeted nanoplatform (cRGD@TAT-DINPs), which co-delivered anticancer drug doxorubicin (DOX) and biocompatible dye indocyanine green (ICG) to realize combined chemo/photothermal/photodynamic therapy of cancer in vitro. The resulting nanoparticles showed favorable monodispersity and colloidal stability. Impressively, the DOX could be released in a promoted manner once the nanoparticles were exposed to NIR light. Confocal laser scanning microscopy (CLSM) and flow cytometry analysis demonstrated an immensely enhanced cellular accumulation of DOX after the simultaneous introduction of targeted ligand cRGD and CPP TAT. In addition, the obtained nanoparticles exhibited explosive temperature elevation and reactive oxygen species (ROS) generation mediated by encapsulated ICG under NIR irradiation, and in vitro cytotoxicity assay confirmed the cRGD@TAT-DINPs had an increasing cytotoxicity and excellent synergistic inhibition capacity. Thus, TAT-based nanosystems provide a high-efficient drug delivery strategy for optimizing combined therapy efficiency of cancer. • TAT peptide was shielded by long PEG chains, but the cellular internalization of nanoparticles was evidently enhanced by TAT. • Anticancer drug DOX could be released in a promoted manner once the nanoparticles were exposed to NIR light. • Biodegradable dye ICG could efficiently convert NIR light into violent heat and plentiful ROS. • The therapy efficacy of resulting nanoparticles was dramatically improved under NIR light. [ABSTRACT FROM AUTHOR]